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cmt21 57a w rev 0.8 | page 1 / 31 www. hoperf .com cmt2157 aw 240 ? 96 0 mhz (g)fsk/ ook stand - alone transmitter with encoder copyright ? by cmostek features ? embedded eeprom ? very easy development with rfpdk ? all features programmable ? frequency rang e: 240 to 960 mhz ? fsk, gfsk and ook modulation ? symbol rate: ? 0.5 to 100 k s ps (fsk/gfsk) ? 0.5 to 4 0 k s ps (ook) ? deviation: 1.0 to 200 khz ? output power: - 10 to +13 dbm ? sleep current : < 2 0 na ? stand - alone, no ext ernal mcu control required ? embedded 1920, 1527 and 2262 data encoder ? up to 7 configurable dat a pins for push buttons ? led indicator for low battery detection and transmission ? sync id auto - study w ith cmostek receiver ? fcc / etsi compliant ? rohs compliant ? 14- pin so p package applications ? low - cost consumer electronics applications ? home and building automation ? remote fan controllers ? infrared transmitter replacements ? industrial monitoring and controls ? remote lighting control ? wireless alarm and security systems ? remote keyless entry (rke) descriptions the cmt215 7 a w is a true single - chip, highly flexible, high performance, (g)fsk/ ook rf transmitter with embedded data encoder ideal ly for 240 to 96 0 mhz wireless applications . the device integrates a data en coder that is not only compatible with the most common used encoding format of 1527 and 2262, but also a more efficient, flexible and powerf ul format of 1920 designed by cmostek . up to 7 configurable push buttons are supported in multiple button modes. when pairing the device to cmostek receiver, the synchronization id can be programmed into both of the transmitter and receiver during the manufacturing phase, or studied by the receiver from the transmitter remotely by end customers. an embedded eeprom allows the rf and encoder pa rameters to be programmed into the chip using the cmostek usb programmer and the rfpdk. alternatively, in stock product of 868.35 mhz is available for immediate demands with out the need of eeprom programming. the cmt215 7 a w is part of the cmostek nextgenrf t m family, together with cmt225x series receivers , they enable ultra low cost, low power consumption rf links. ordering information part number frequency package moq cmt215 7aw - esr 868.35 mhz t&r 2,500 pcs cmt215 7aw - esb 868.35 mhz tube 1, 0 00 pcs more ordering info: see page 26 1 2 3 4 5 6 7 14 13 12 10 9 8 11 led vdd gnd rfo k7 k6 k5 xtal clk data k1 k2 k3 k4 cmt21 57 aw so p14
cmt21 57a w rev 0.8 | page 2 / 31 www. hoperf .com typical application ant vdd u1 c2 l2 c1 l1 c0 sw7 sw6 sw5 led vdd gnd rfo k7 k6 k5 1 2 3 4 5 6 7 d1 8 9 10 11 12 13 14 sw4 sw3 sw2 sw1 xtal clk data k1 k2 k3 k4 x1 clk data clk data j1 1 2 3 4 vdd cmt2157aw note: connector j1 is for eeprom programming figure 1 . cmt21 5 7 aw typical application schematic table 1 . bom of 433.92 /868.35 mhz typical application designator descriptions value unit manufacturer 433.92 mhz 868.35 mhz u1 cmt2157 aw , 240 ? 960 mh z (g)fsk/ o ok s tand - a lone t ransmitter with e ncoder - - cmostek x1 20 ppm, smd32*25 mm crystal 26 mhz epson c0 20%, 0402 x7r, 25 v 0.1 uf murata grm15 c1 5%, 0402 np0, 50 v 82 82 pf murata grm15 c2 5%, 0402 np0, 50 v 9 .1 3.9 pf murata grm15 l1 5%, 0603 multi - layer chip inductor 180 100 nh murata lqg18 l2 5%, 0603 multi - layer chip inductor 22 5.1 nh murata lqg18 d1 d0603, red led - - - sw [ 7 : 1 ] push buttons - - -
cmt21 57a w rev 0.8 | page 3 / 31 www. hoperf .com abbreviations abbreviations used in this data sheet are described below an application notes obw occupied bandwidth bom bill of materials ook on - off keying bsc basic spacing between centers pa power amplifier bw bandwidth pc personal computer dc direct current pcb printed circuit board eeprom electrically erasable programmable read - only memory pll phase lock loop pn phase noise esd electro - static discharge rbw resolution bandwidth esr equivalent series resistance rclk reference clock fsk frequency s hift k eying rf radio frequency gfsk gauss frequency shift keying rfpdk rf product development kit gui graphical user interface rohs restriction of hazardous substances ic integrated circuit rx receiving, receiver ldo low drop - out sot small - outline transistor max maximum tbd to be determined mcu microcontroller unit tx transmission, transmitter min minimum typ typical moq minimum order quantity xo/xosc crystal oscillator np0 negative - positive - zero xtal crystal
cmt21 57a w rev 0.8 | page 4 / 31 www. hoperf .com table of contents 1. electrical characteristics ............................................................................................................................................ 5 1.1 recommended operating conditions ................................................................................................................... 5 1.2 absolute maximum ratings ................................................................................................................................... 5 1.3 transmitter specifications ..................................................................................................................................... 6 1.4 crystal oscillator ................................................................................................................................................... 7 2. pin descriptions .......................................................................................................................................................... 8 3. typical performance characteristics ......................................................................................................................... 9 4. typical application schematics ............................................................................................................................... 10 4.1 low - cost application schematic ......................................................................................................................... 10 4.2 fcc/etsi compliant application schematic ....................................................................................................... 11 5. functional descriptions ............................................................................................................................................ 12 5.1 overview ............................................................................................................................................................. 12 5.2 modulation, frequency, deviation and symbol rate .......................................................................................... 12 5.3 embedded eeprom and rfpdk ...................................................................................................................... 13 5.4 power amplifier ................................................................................................................................................... 15 5.5 pa ramping ........................................................................................................................................................ 15 5.6 working states .................................................................................................................................................... 16 5.7 the encode r ........................................................................................................................................................ 17 5.7.1 1920 packet structure ............................................................................................................................................17 5.7.2 1527 packet structure ............................................................................................................................................18 5.7. 3 2262 packet structure ............................................................................................................................................19 5.8 id study .............................................................................................................................................................. 20 5.9 button modes ...................................................................................................................................................... 21 5.9.1 normal ......................................................................................................................................................................21 5.9.2 matrix ........................................................................................................................................................................22 5.9.3 toggle .......................................................................................................................................................................23 5.9.4 pwm .........................................................................................................................................................................23 5.10 led driving capability ........................................................................................................................................ 24 5.11 low battery detection (lbd) ............................................................................................................................... 24 5.12 crystal oscillator and rclk ................................................................................................................................ 24 6. ordering information ................................................................................................................................................. 26 7. package outline ......................................................................................................................................................... 27 8. top marking ............................................................................................................................................................... 28 8.1 cmt2157aw top marking .................................................................................................................................. 28 9. other documentations .............................................................................................................................................. 29 10. document change list .............................................................................................................................................. 30 11. contact information .................................................................................................................................................. 31
cmt21 57a w rev 0.8 | page 5 / 31 www. hoperf .com 1. electrical characteristics v dd = 3.3 v, t op = 25 , f rf = 433.92 mhz, output power is +10 dbm terminated in a matched 50 impedance, unless otherwise noted . 1.1 recommended operating conditions table 2 . recommended operation conditions parameter symbol conditions min typ max unit operation voltage supply v dd 1.8 3.6 v operation temperature t op - 40 85 supply voltage slew rate 1 mv/us 1.2 absolute maximum ratings table 3 . absolute maximum ratings [1] parameter symbol conditions min max unit supply voltage v dd - 0.3 3.6 v interface voltage v in - 0.3 v dd + 0.3 v junction temperature t j - 40 125 storage temperature t stg - 50 150 soldering temperature t sdr lasts at least 30 seconds 255 esd rating human body model (hbm) - 2 2 kv latch - up current @ 85 - 100 100 ma note: [1]. stresses above those listed as ?absolute maximum ratings? may cause permanent damage to the device. this is a stress rating only and functional operation of the device under these conditions is not implied. exposure to maximum rating conditions for extended periods may affect device reliability . caution! esd sensitive device. precaution should be used when handling the device in order to prevent permanent damage.
cmt21 57a w rev 0.8 | page 6 / 31 www. hoperf .com 1.3 transmitter specifications table 4 . transmitter specifications parameter symbol conditions min typ max unit frequency range [1] f rf 240 960 mhz synthesizer frequency resolution f res f rf 480 mhz 198 hz f rf > 480 mhz 397 hz symbol rate sr fsk/ g fsk 0.5 100 ksps ook 0.5 4 0 ksps (g)fsk modulation deviation range f d e v 1 200 khz bandwidth - time product bt gfsk modulation - 0.5 - - maximum output power p out (max) +13 dbm minimum output power p out ( m in) - 10 dbm output power step size p step 1 db pa ramping time [2] t ramp 0 1024 us current consumption [3] @ 433.92 mhz i dd- 433.92 ook, 0 dbm 6 ma ook, +10 dbm 8.5 ma ook, +13 dbm 10.2 ma fsk, 0 dbm 10.8 ma fsk, +10 dbm 23.8 ma fsk, +13 dbm 32 ma current consumption [3] @ 868.35 mhz i dd- 868 .35 ook, 0 dbm 6.1 ma ook, +10 dbm 9.3 ma ook, +13 dbm 11.2 ma fsk, 0 dbm 12.3 ma fsk, +10 dbm 26.7 ma fsk, +13 dbm 35.3 ma sleep current i sleep 20 na frequency tune time t tune 370 us phase noise @ 433.92 mhz pn 433.92 100 khz offset from f rf - 80 dbc/hz 600 khz offset from f rf - 9 6 dbc/hz 1.2 mhz offset from f rf - 108 dbc/hz phase noise @ 868.35 mhz pn 868 .35 100 khz offset from f rf - 7 4 dbc/hz 600 khz offset from f rf - 9 0 dbc/hz 1.2 mhz offset from f rf - 102 dbc/hz harmonics output for 433.92 mhz [ 4 ] h2 433.92 2 nd harm @ 867.84 mhz, +13 dbm p out - 52 dbm h3 433.92 3 rd harm @ 1301.76 mhz, +13 dbm p out - 57 dbm harmonics output for 868.35 mhz [ 4 ] h2 868 .35 2 nd harm @ 1736 .7 mhz, +13 dbm p out - 6 8 dbm h3 868 .35 3 rd harm @ 260 5.05 mhz, +13 dbm p out - 5 2 dbm ook extinction ration 60 db note s : [1]. the frequency range is continuous over the specified range . [2]. 0 and 2 n us, n = 0 to 10, when set to ?0?, the pa output power will ramp to its configured value in the shortest possible time . [3]. t he working currents are tested with: 1527 packet format/normal button mode/ 4 push buttons/sync id = 0/no led . [4]. the harmonics output is measured with the application shown as figure 10 .
cmt21 57a w rev 0.8 | page 7 / 31 www. hoperf .com 1.4 c rystal oscillator table 5 . crystal oscillator specifications parameter symbol conditions min typ max unit crystal frequency [1] f xtal 26 26 26 mhz crystal tolerance [2] 20 ppm load capacitance [ 3 ] c load 12 20 pf crystal esr rm 60 xtal startup t ime [4] t xtal 400 us note s : [1]. the cmt2157 aw can directly work with external 26 mhz reference clock input to xtal pin ( a coupl ing capacitor is required) with amplitude 0.3 to 0.7 vpp . [2]. this is the total tolerance including (1) initial tolerance, (2) crystal loading, (3) aging, and (4) temperature dependence. the acceptable crystal tolerance depends on rf frequency and channel spacing/bandwidth. [3]. t he required crystal load capacitance is integrated on - chip to minimize the number of external c omponents . [4]. this parameter is to a large degree crystal dependent .
cmt21 57a w rev 0.8 | page 8 / 31 www. hoperf .com 2. pin descriptions 1 2 3 4 5 6 7 14 13 12 10 9 8 11 led vdd gnd rfo k7 k6 k5 xtal clk data k1 k2 k3 k4 figure 2 . cmt21 5 7 aw pin assignments table 6 . cmt2157a w pin descriptions pin number name i/o descriptions 1 led o led driver, active low 2 vdd i power supply input 3 gnd i ground 4 rfo o power amplifier output 5 - 11 k[7:1] i push button 7 to 1 12 data io data pin to access the embedded eeprom , internally pull ed up to vdd 13 clk i clock pin to access the embedded eeprom , internally pull ed up to vdd 14 xtal i 26 mhz single - ended crystal oscillator input or external 26 mhz reference clock input
cmt21 57a w rev 0.8 | page 9 / 31 www. hoperf .com 3. typical performance characteristics 13.4dbm @ 433.92 mhz - 56.8 dbm @ 435.12 mhz - 60 - 50 - 40 - 30 - 20 - 10 0 10 20 432.42 432.72 433.02 433.32 433.62 433.92 434.22 434.52 434.82 435.12 435.42 power (dbm) frequency (mhz) phase noise @ 433.92 mhz 13.0 dbm @ 868.35 mhz - 55.9 dbm @ 869.55 mhz - 65 - 55 - 45 - 35 - 25 - 15 - 5 5 15 866.85 867.1 867.35 867.6 867.85 868.1 868.35 868.6 868.85 869.1 869.35 869.6 869.85 power (dbm) frequency (mhz) phase noise @ 868.35 mhz - 60 - 50 - 40 - 30 - 20 - 10 0 10 20 432.92 433.12 433.32 433.52 433.72 433.92 434.12 434.32 434.52 434.72 434.92 power (dbm) frequency (mhz) ook spectrum - 50 - 40 - 30 - 20 - 10 0 10 20 433.62 433.72 433.82 433.92 434.02 434.12 434.22 power (dbm) frequency (mhz) fsk vs. gfsk fsk gfsk - 50 - 40 - 30 - 20 - 10 0 10 433.17 433.37 433.57 433.77 433.97 434.17 434.37 434.57 power (dbm) frequency (mhz) spectrum of various pa ramping options 1024 us 512 us 256 us 128 us 64 us 32 us sr = 1.2 ksps - 2 0 2 4 6 8 10 12 14 16 1.6 1.8 2 2.2 2.4 2.6 2.8 3 3.2 3.4 3.6 3.8 power (dbm) supply voltage (v) p out vs. v dd 13 dbm 10 dbm 0 dbm figure 3 . phase noise, f rf = 868.35 mhz, p out = +13 db m, rbw = 10 khz, un - encoded figure 5 . ook spectrum , p out = +10 dbm, t ramp = 32 us figure 6 . fsk/gfsk spectrum, sr = 9.6 ksps, f dev = 15 khz figure 7 . spectrum of pa ramping, sr = 1.2 ksps, p out = +10 dbm figure 4 . phase noise, f rf = 433.92 mhz, p out = + 13 dbm, rbw = 10 khz, un - encoded figure 8 . output power vs. supply voltages, f rf = 433.92 mhz
cmt21 57a w rev 0.8 | page 10 / 31 www. hoperf .com 4. typical application schematics 4.1 low - cost application schematic ant vdd u1 c2 l2 c1 l1 c0 sw7 sw6 sw5 led vdd gnd rfo k7 k6 k5 1 2 3 4 5 6 7 d1 8 9 10 11 12 13 14 sw4 sw3 sw2 sw1 xtal clk data k1 k2 k3 k4 x1 clk data clk data j1 1 2 3 4 vdd cmt2157aw note: connector j1 is for eeprom programming figure 9 . low - cost application sch ematic note s : 1. connector j1 is a must for the cmt2157 aw eeprom access during development or manufacture phase . 2. t he general layout guidelines are listed below. for more design details, please refer to ?an1 1 1 cmt215 x schematic and pcb layout design guideline? ? u se as much continuous ground plane metallization as possible. ? use as many grounding vias (especially near to the gnd pins) as possible to minimize series parasitic inductance between the ground pour and the gnd pins . ? avoid using long and/or thin transmission lines to connect the components . ? a void placing the nearby inductors in the same orientation to reduce the coupling between them . ? place c 0 as close to the cmt2157 aw as possible for better filtering . 3. t he t able below shows the bom of 433.92 /868.3 5 mhz low - cost application. for t he bom of more application s , please refer t o ? an1 11 cmt215 x schematic and pcb layout design guideline ? . table 7 . bom of 433.92 /868.35 mhz low - cost application designator descriptions value unit manufacturer 433.92 mhz 868.35 mhz u1 cmt2157 aw , 240 ? 960 mh z (g)fsk/ o ok s tand - a lone t ransmitter with e ncoder - - cmostek x1 20 ppm, smd32*25 mm crystal 26 mhz epson c0 20%, 0402 x7r, 25 v 0.1 uf murata grm15 c1 5%, 0402 np0, 50 v 82 82 pf murata grm15 c2 5%, 0402 np0, 50 v 9 .1 3.9 pf murata grm15 l1 5%, 0603 multi - layer chip inductor 180 100 nh murata lqg18 l2 5%, 0603 multi - layer chip inductor 22 5.1 nh murata lqg18 d1 d0603, red led - - - sw [ 7 :1] push buttons - - -
cmt21 57a w rev 0.8 | page 11 / 31 www. hoperf .com 4.2 fcc/etsi compliant application schematic vdd u1 c2 l2 c1 l1 c0 sw7 sw6 sw5 led vdd gnd rfo k7 k6 k5 1 2 3 4 5 6 7 d1 8 9 10 11 12 13 14 sw4 sw3 sw2 sw1 xtal clk data k1 k2 k3 k4 x1 clk data cmt2157aw ant l3 c3 clk data j1 1 2 3 4 vdd note: connector j1 is for eeprom programming figure 10 . fcc/etsi compliant application schematic note s : 1. connector j1 is a must for the cmt2157 aw eeprom access during development or manufacture phase . 2. t he general layout guidelines are listed below. for more design details, please refer to ? an1 11 cmt215 x schematic and pcb layout design guideline ? . ? u se as much continuous ground plane metallization as possible. ? use as many grounding vias (especially near to the gnd pins) as possible to minimize series parasitic inductance between the ground pour and the gnd pins. ? avoid using long and/or thin transmission lines to connect the components. ? a void placing the nearby inductors in the same orientation to reduce the coupling between them . ? place c 0 as close to the cmt2157 aw as possible for better filtering . 3. the t able below shows the bom of 433.92 /868.35 mhz fcc/etsi compliant application. for the bom of more appl ication, please refer to ? an1 11 cmt215 x schematic and pcb layout design guideline ? . table 8 . bom of 433.92 /868.35 mhz fcc/etsi compliant application designator descriptions value unit manufacturer 433.92 mhz 868.35 mhz u1 cmt2157 aw , 240 ? 96 0 mh z (g)fsk/ o ok s tand - a lone t ransmitter with e ncoder - - cmostek x 1 20 ppm , smd32*25 mm crystal 26 mhz epson c 0 20% , 0402 x7r , 25 v 0.1 uf murata grm15 c1 5% , 0402 np0, 50 v 68 68 pf murata grm15 c 2 5% , 0402 np0, 50 v 15 10 pf murata grm15 c3 5% , 0402 np0, 50 v 15 6.8 pf murata grm15 l1 5% , 0603 multi - layer chip inductor 180 100 nh murata lqg 18 l 2 5% , 0603 multi - layer chip inductor 36 5.6 nh murata lqg 18 l3 5% , 0603 multi - layer chip inductor 18 6.8 nh murata lqg 18 d1 d0603, red led - - - sw [ 7 :0] push buttons - - -
cmt21 57a w rev 0.8 | page 12 / 31 www. hoperf .com 5. functional descriptions modulator ldos vdd gnd clk k0/data xtal rfo loop filter pfd/cp frac-n div encoder ramp-control interface & control logics eeprom por pa vco xosc bandgap led driver led k[7:1] k0 figure 11 . cmt2157 aw functional block diagram 5.1 overview the cmt2157 aw is a true single - chip, highly flexible, high performance, ook rf transmitter with embedded data encoder ideal for 240 to 960 mhz wireless applications . i t is part of the cmostek nextgenrf tm family, which include s a complete line of transmitters , receiver s and transceivers. the device integrates a data en coder that is not only compatible with the most common used encoding format of 1527 and 2262, but also a more efficient, flexible and powerful format of 1920 designed by cmostek . up to 7 configurabl e push buttons are supported in multiple button modes. t he device is optimized for the low system cost, low power consumption, battery powered application with its highly integrated and low power design. t he functional block diagram of the cmt2157 aw is sh own in f igure above . t he cmt2157 aw is based on direct synthesis of the rf freque ncy by means of a fully integrated low - noise fractional - n frequency synthesizer. i t uses a 1 - pin crystal oscillator circuit with the required crystal load capacitance integrated on - chip to minimize the number of external c omponents . e very analog block is calibrated on each power - on reset (por) to an internal reference voltage source . t he calibration can help the chip to finely work under different temperatures and supply voltages. the transmission is triggered by pressing the push button(s). the data is modulated and sent out by a highly efficient pa which output power can be configured from - 10 to +13 dbm in 1 db step size. rf frequency , pa output power and other product features can be programmed into the embedded eeprom by the rfpdk and usb programmer . this saves the cost and simplif ies the product development and manufacturing effort . a lternatively, in stock product of 868.35 mhz is av ailable for immediate demands with no need of eeprom programming. t he cmt2157 aw operates from 1.8 to 3.6 v so that it can finely work with most batteries to their useful power limits. it only consu mes 26.7 ma when transmitting +10 dbm fsk signal at 868.35 mhz under 3. 3 v supply voltage. 5.2 modulation, frequency , deviation and symbol rate the cmt2157 aw supports gfsk/fsk modulation with the symbol rate up to 100 ksps, as well as ook modulation with the symbol rate up to 4 0 ksps . t he supported deviation of the (g)fsk modulation ranges from 1 to 200 khz. it continuously covers the frequency range from 240 to 960 mhz, including the license free ism frequency band around 315 mhz , 433.92 mhz, 868.35 mhz and 9 15 mhz. t he device contains a high spectrum purity low power fractional - n frequency synthesizer with output frequency resolution better than 198 hz when the frequency is less tha n 480 mh z, and is about 397 hz when the frequency is large r th a n 480 mhz . see table 9 for the modulation, frequency , deviation and symbol rate specifications .
cmt21 57a w rev 0.8 | page 13 / 31 www. hoperf .com table 9 . modulation, frequency , deviation and symbol rate parameter value unit modulation (g)fsk/ ook - frequency 240 to 96 0 mhz deviation 1 to 200 khz frequency resolution (f rf 480 mhz) 198 hz frequency resolution (f rf > 480 mhz) 397 hz symbol rate (fsk/gfsk) 0.5 to 100 ksps symbol rate (ook) 0.5 to 4 0 ksps 5.3 embedded eepro m and rfpdk the rfpdk (rf product s development kit) is a very user - friendly software tool delivered for the user configur ing the cmt2157 aw in the most intuitional way. the use r only needs to fill in/ select the proper value of each parameter and click the ?burn? button to complete the chip configuration. no register access and control is required in th e application program . see f igure below for the accessing of the eeprom and table 10 for the summary of all the configurable parameters of the cmt2157 aw on the rfpdk . cmt2157aw interface cmostek usb programmer clk data rfpdk eeprom figure 12 . accessing embedded eeprom for more detail s of the cmostek usb programmer and the rfpdk , please refer to ? an 1 1 3 cmt215 0 a / 2250 (1) a one - way rf link development kits user?s guide? . f or the detail of cmt2157 aw configurations with the rfpdk, please refer to ? an142 cmt2157a configuration guideline ? . table 10. configurable parameters in rfpdk category parameters descriptions default mode rf settings frequency t o input a desired transmitting radio frequency in the range from 240 to 960 mhz . the step size is 0.001 mhz. 868.35 mhz basic advanced modulation the option is fsk or gfsk and ook. fsk basic advanced tx power to select a proper transmitting output power from - 10 dbm to +14 dbm , 1 dbm margin is given above +13 dbm. + 1 3 dbm basic advanced xtal cload on - chip xosc load capacitance options: from 1 0 to 2 2 pf . 15 .00 pf basic advanced symbol rate to determines the symbol rate of the transmitted data: from 0.5 to 100 ksps in (g)fsk mode and 0.5 to 40 ksps in ook mode. 2.4 basic advanced
cmt21 57a w rev 0.8 | page 14 / 31 www. hoperf .com category parameters descriptions default mode deviation the fsk frequency deviation . the range is from 1 to 200 khz. 35 khz basic advanced pa ramping to control pa output power ramp up/down time, options are 0 and 2 n us (n from 0 to 10) . 0 us advanced led driving capability this defines the driving current of the led pin. the options are: disable, 5, 10, 15 or 20 ma. 5 ma advanced lbd threshold this defines the low battery detection threshold. the options are: disable, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7 or 2.8 v. 2.4 v advanced data representation to select whether the frequency ?fo + fdev? represent data 0 or 1 . the options are: 0: f - high 1: f - low, or 0: f - low 1: f - high. 0: f - low 1: f - high advanced encoder settings encoder select the packet encoding format, the options are: 1920, 1527 and 2262. see table 13 , table 14 and table 15 for the c onfigurable p arameters in each packet. 1527 basic advanced bit format this tells the device how many symbols are used to construct a single bit in the 1920 mode. the options are: 3, 4, 5 or 6 sym/bit. the bit format is fixed at 4 sym/bit in 1527 mode and 8 sym/bit in 2262 mode. i t is only available in 1920 mode. 3 basic advanced number of packets this defines the minimum number of packet ( s ) being transmitted during each button pr essing action. i t also defines the number of packet (s) being transmitted during each periodic transmission. the range is from 1 to 256. 1 advanced packet interval this defines the time interval amount two consecutive transmitted packets. the unit is in symbol, the range is from 0 to 255 symbols of zero. 0 symbol s of zero basic advanced push button settings button mode select the button encoding mode , the options are: normal , matrix, toggle and pwm . for 1920 and 1527 format, all these button modes are supported; for 2262 format, only normal button mode is supported. normal basic advanced on/off button(s) select the numbers of on/off button for toggle and pwm button modes , the options are : single or separated. single basic advanced number of button(s) this option is only available in normal button mode, and encoder is set to 1920 and 1527. it defines the number of activated button(s) to be used in the application. the range is from 1 to 7. 4 basic advanced data inversion allow the user to select whether or not to inverse the transmitted data bits values in the normal and toggle button mode. the options are: no or yes. no advanced periodic transmission turn on/off the periodic transmission mode of the device. the options are: on or off. off advanced
cmt21 57a w rev 0.8 | page 15 / 31 www. hoperf .com category parameters descriptions default mode periodic time this parameter is only available when periodic transmission is turned on. it defines the periodic time for transmitting a fixed set of data. the range is from 2 to 7683.512 s, accurate to 3 decimal points. i t is only available when periodic transmission is on. 1.000 s advanced study settings id study turn on/off the sync id study function, the options are: on or off. the id study is only supported in 1920 and 1527 mode. off advanced study trigger time this parameter is only available when id study is turned on. it defines the time from the instance of pressing the study button to the instance at which the device starts to transmit the study packets. the range is from 1 to 15 second(s). 5 s advanced study button this parameter is only available when id study is turned on. it defines which button is used to trigger the transmission of the study packets. the options are the current buttons used in the push button settings. pin 11 (k1) advanced study power this parameter is only available when id study is turned on. it defines the pa power when the device is transmitting the study packets. the range is from ? 10 to +14 dbm. - 6 dbm basic advanced 5.4 power amplifier a high ly efficien t single - ended power amplifier (pa) is integrated in the cmt2157 aw to transmit the modulated signal out . depending on the application, the user can design a matching network for the pa to exhibit optimum efficiency at the desired output power for a wide range of antennas, such as loop or monopole antenna. typical applicat ion schematics and the required bom are shown in ?chapter 4 typical application schematic?. for the schematic, layout guideline and the other detai l ed information please refer t o ?an1 1 1 cmt215 x schematic and pcb layout design guideline?. the output power of the pa can be configured by the user within the range from - 10 dbm to +13 dbm in 1 db step size using the cmostek usb programmer and rfpdk. 5.5 pa ramping when the pa is switched on or off quickly, its changing input impedance momentarily disturbs the vco output frequency. this phenomenon is called vco pulling, and it manifests as spectral splatter or spurs in the output spectrum around the desired carrier frequency. by gradually ramping the pa on and off, pa transient spurs are minimized. the cmt2157 aw has built - in pa ramping configurabili ty with options of 0, 1, 2, 4, 8, 16, 32, 64, 128, 256, 512 and 1024 us, a s shown in figure 13 . w hen the option is set to ? 0 ? , the pa output power wil l ramp up to its configured value in the shortest possible time. the ramp down time is identical to the ramp up time in the same configuration. cmostek recommends that the maximum symbol rate should be no higher than 1/2 of the pa ramping ? rate ? , as shown in the formula below: sr max 0.5 * ( 1 t ramp )
cmt21 57a w rev 0.8 | page 16 / 31 www. hoperf .com i n which the pa ramping ? rate ? is given by (1/t ramp ). i n other words, by knowing the maximum symbol rate in the application, the pa ramping time can be calculated by: t ramp 0.5 * ( 1 sr max ) the user can select one of the values of the t ramp in the available options that meet the above requirement. if somehow the t ramp is set to be longer than ? 0.5 * (1/sr max ) ? , it will possibly bring additional challenges to the ook demodulation of the rx device. f or more detail of calculating t ramp , please refer to ? an1 4 2 cmt 2157a configuration guideline ? . time rfo amplitude time data logic 1 logic 0 1024 us 512 us 8 us 4 us 2 us 1 us 0 us figure 13 . pa ramp ing time 5.6 working states t he cmt2157 aw has following 4 different working states: sleep, xo - startup , tune and transmit . the device stays in the sleep state when no transmission is performed. once the button(s) is/are pressed, the device goes through the sequence of sleep ? xo - startup ? tune ? transmit to transmit the data. after the transmission the device goes back to the sleep state. when the device works in the periodic transmission mode, the device periodically wakes up from the sleep state, goes the same sequence, performs the transmissio n and goes back to the sleep state. all the details of push button(s) function and periodic transmission can be referred to ? an1 4 2 cmt 2157a configuration guideline ? . sleep w hen the cmt2157a w is in the sleep state , all the internal blocks are turned off and the current consumption is minimized to 20 na typically . xo - start up once the cmt2157 aw received the valid control signal, it will go into the xo - startup state , and the internal xo start s to work. the user has to wait for the t xtal to allow the xo to get stable. the t xtal is to a large degree crystal dependent . a typical value of t xtal is provided in the table 11 . tune t he frequency synthesizer will tune the cmt2157 aw to the desired frequency in the time t tune . t he pa can be turned on to transmit the data generated by the embedded encoder only after the tune state is done . transmit t he cmt2157 aw start s to modulate and transmit the d a ta . the data packets being transmitted are generated by the embedded encoder, and they are determined by the encoder selected, the button mode and the button being pressed .
cmt21 57a w rev 0.8 | page 17 / 31 www. hoperf .com table 11 . main timing spec i n different working states parameter symbol min typ max unit xtal startup time [1] t xtal 400 us time to t une to d esired f requency [2] t tune 370 us note s : [1]. this parameter is to a large degree crystal dependent . [2]. from xo stable to ready to transmit . 5.7 the en coder the device supports 3 types of encoding formats : 1920, 1527 and 2262. the packets of these 3 modes have different structures which will be introduced in the below sub - sections. t he t able below summarize s the major features of the 3 encoding format s . table 12. feature summary of the 3 en coding formats format bit format (sym/bit) sync id length (bits) data length (bits) crc id study button mode s [1] 1920 3/4/5/6 1 ? 32 1 ? 7 support support all 1527 4 20 1 ? 7 na support all 2262 8 6 ? 11 1 ? 6 na not support normal mode note: [1]. button modes include normal mode, matrix mode, toggle mode and pwm mode. all the details of these 3 types of encoding formats are given in the doc ument ?an1 4 2 cmt 2157a configuration guideline?. the following sections only give the abstracts of these formats. in the below explanations, s ome elements in the packet are measured in the unit of ?symbol?, while some of them are measured in the unit of ?bi t?. for those which have the unit of ?bit?, one ?bit? is constructed (encoded) by several ?symbols?. in the figures, ?sym? represents the word ?symbol?. 5.7.1 1920 packet structure two types of packet structures are supported for 1920 format: normal packet and study packet. the following configurable parameters are shared by the two structures. table 13. configurable parameters in 1920 packet parameter descriptions default mode preamble the size of the valid preamble, the options are: none or 16- symbol. none basic advanced address (sync id) length the range of the sync id length is from 1 to 32 bits. 32- bit basic advanced address (sync id) value the value of the sync id has the range from 0 to 2 l ength - 1 . 0 basic advanced normal packet the normal packet is used to control the data pins of the cmostek receiver cmt2250 aw or pwm output of the cmt2251 aw . it contains a 16 - symbol preamble, a 32 - symbol head_n (which indicat es that the current packet is a n ormal packet rather than a study packet) , a sync id, a configurable data field and an 8 - symbol crc.
cmt21 57a w rev 0.8 | page 18 / 31 www. hoperf .com preamble 16 symbols address (sync id) configurable 1-32 bits d0 1 bit d1 1 bit d2 1 bit d3 1 bit crc 8 symbols head_n 32 symbols figure 14 . 1920 normal packet structure study packet the study packet is used for the receiver to learn the sync id from the cmt2157 aw in order to pair the two devices . it contains an optional preamble, a 32 - symbol head_s, a sync id and an 8 - symbol crc. preamble (optional) 16-symbol crc 8-symbol head_s 32-symbol address (sync id) configurable 1-32 bits figure 15 . 1920 study packet structure bit format in 1920 packet, a single bit can be constructed (encoded) by 3, 4, 5 or 6 symbols. the user can select the desired value of t he ?bit format? parameter on the rfpdk. please note that only the sync id fie ld and the d0, d1, d2, d3 , d4, d5, d6 have the unit of ?bit?. 2 sym 2 sym 1 sym 1 sym bit 1 bit 0 1 sym 1 sym 3 sym 3 sym bit 1 bit 0 3 sym 2 sym bit 1 2 sym 3 sym bit 0 2 sym 1 sym bit 1 1 sym 2 sym 1 sym 1 sym bit 0 1 sym 3 sym 3 symbols/bit 4 symbols/bit 5 symbols/bit 6 symbols/bit figure 16 . 1920 bit format options 5.7.2 1 527 packet structure two types of packet structures are supported for 1527 format: normal packet and study packet. the fo llowing configurable para meter is shared by the two structures. table 14. configurable parameters in 1527 packet parameter descriptions default mode address (sync id) value the range of the sync id value is from 0 to 2 20 - 1. this is because the sync id length is fixed at 20 for 1527. 0 basic advanced in the traditional 1527 format, 8 osc clocks are equal to 1 lck, 4 lck are equal to 1 symbol. by using the cmt2250 aw pairing with cmt2157 aw , the user does not need to adjust the osc to determine the symbol rate, because the symbol rate is directly programmed. the bit format is fixed at 4 symbols (16 lck) per bit.
cmt21 57a w rev 0.8 | page 19 / 31 www. hoperf .com normal packet the traditional 1527 packet contains a 32- symbol sync , a 20- bit ad dress ( s ync id ) and 4 - bit d ata . cmostek has defined a 1527 study packet to support the id study in 1527 mode. the traditional packet introduced here is called the ? normal packet ? . address (sync id) configurable 20 bits d0 1 bit d1 1 bit d2 1 bit d3 1 bit sync 32 symbols figure 17 . 1527 normal packet structure study packet the 1527 study packet contains a 32- symbol head_s and a 20 - bit address ( s ync id ), as shown below. head_s 32-symbol address (sync id) 20 bits figure 18 . 1527 study packet structure bit format in 1527 packet, a single bit is constructed by 4 symbols, as shown below. the user can select the desired value of the ?bit format? parameter on the rfpdk. please note that only the sync id fi eld and the d0, d1, d2, d3 , d4, d5, d6 field have the unit of ?bit?. 1 sym 1 sym 3 sym 3 sym bit 1 bit 0 figure 19 . 1527 bit format options 5.7.3 2262 packet structure id study is not supported in 2262 mode. only one packet structure is supported. table 15. configurable parameters in 2262 packet parameter descriptions default mode address (sync id) length this is the range of the sync id length. the range is from 6 to 11 bits. this parameter also defines the number of data bits, because the total number of sync id and data bits is fixed at 12. 8 - bit basic advanced address (sync id) value the value of each bit of the sync id can only be represented by 0, 1 or f. 0 0000000 basic advanced in the traditional 2262 format, 4 osc clocks (1 osc clock cycle is notated as 1 ) are equal to 1 symbol. by using the cmostek products , the user does not need to adjust the osc to define the symbol rate, because the symbol rate is directly programmed. the bit format is fixed at 8 symbols per bit. normal packet the traditional 2262 packet contains a n address ( s ync id ), a d ata, and a 32 - symbol sync.
cmt21 57a w rev 0.8 | page 20 / 31 www. hoperf .com address (sync id) configurable 8-11 bits data 4-1 bit(s) sync 32 symbols figure 20 . 2262 packet structure bit format in 2262 packet, a single bit is constructed by 8 symbols, as shown below. please note that only the address (sync id) field and the data field have the unit of bit. in the below diagram, 1 osc clock cycle is notated as 1 referring to the original 22 62 timing descriptions. 3 sym (12 ) 1 sym (4 ) 3 sym (12 ) 1 sym (4 ) bit 1 3 sym (12 ) 1 sym (4 ) bit 0 3 sym (12 ) 1 sym (4 ) 3 sym (12 ) 1 sym (4 ) bit f 3 sym (12 ) 1 sym (4 ) figure 21 . 2262 bit format options 5.8 id study the id study function, which is supported in 1920 and 1527 modes , allows the receiver to study the sync id sent by the cmt2157 aw . since then, the receivers sync id is identical to that of the cmt2157 aw and therefore two devices are paired. the lengths of the sync id are different in the different packet formats. in 1920 format, it is from 1 to 32 bits. in 1527 fo rmat, it is fixed at 20 bits. the id study is initialized by the cmt2157 aw . it is done by executing the f ol lowing steps . a n example of cmt2157 aw paring with cmt2250/51 aw is given below. 1. press the study button on the cmt2157a w and hold it over the time defined by the ? study trigger time ? . 2. cmt2157 aw starts to transmit the study packets, wait 1 - 2 seconds then release the study button. 3. try to press a certain button on the cmt2157 aw to check if t he cmt2250 /51 aw react correctly. the figure below shows the timing characteristic after pressing down a study button. the study power is always independently configure from the tx power. in this example, the study power is set smaller than the tx power. one normal packet packet interval study button pressed time study button released study time (default is 5 s) one study packet packet interval tx power = 0 dbm study power = -6 dbm figure 22 . timing of study button pressing event more information about the id study can be found in the d ocument ? an1 4 2 cmt215 7a configuration guideline ? .
cmt21 57a w rev 0.8 | page 21 / 31 www. hoperf .com 5.9 button modes the button modes define the functions of the inpu t pins k 1 ? k 7. t he cmt2157 aw supports 4 different button modes : normal, matrix, toggle and pwm, which are configured on the rfpdk. the following sections give the abstract of each button mode. all the details of the button mode s are given in the doc ument ? an1 4 2 cm t2157a configuration guideline ? . 5.9.1 normal the normal button mode is supported in 1920, 1527 and 2262 format. in this mode, t he buttons are directly mapped to the data field of the pac ket. multiple buttons can be pressed at the same time. for 1920 and 1527, the largest number of buttons is 7 which are defined by the parameter ? number of button(s) ? . for 2262, the largest number of buttons is 6, which is determined by the sync id leng th . the figure below gives an example which 4 push button keys are selected. led vdd gnd rfo k7 k6 k5 xtal clk k0 k1 k2 k3 k4 d0 d1 d2 d3 nc nc nc nc led vdd gnd rfo clk xtal 7 6 5 1 2 3 4 8 9 10 14 13 12 11 figure 23 . normal button mode in normal button mode, the number of button(s) is used to determines the number of data bits in a packet. the table below shows when 4 buttons are used and the pins k 1 ? k 4 are mapp ed to the data d0 ? d 3, ? 1 ? in the p ush b uttons section means the corresponding button(s) is/are pressed , w hile the ?1? in the data bits section means logic ?1? to be transmitted. table 16. mappin g from k 1 - k 4 to d0 - d3 in normal button mode push buttons the data bits k 1 k 2 k 3 k 4 d0 d1 d2 d3 1 0 0 0 1 0 0 0 0 1 0 0 0 1 0 0 1 1 0 0 1 1 0 0 0 0 1 0 0 0 1 0 1 0 1 0 1 0 1 0 0 1 1 0 0 1 1 0 1 1 1 0 1 1 1 0 0 0 0 1 0 0 0 1 1 0 0 1 1 0 0 1 0 1 0 1 0 1 0 1 1 1 0 1 1 1 0 1 0 0 1 1 0 0 1 1 1 0 1 1 1 0 1 1 0 1 1 1 0 1 1 1 1 1 1 1 1 1 1 1
cmt21 57a w rev 0.8 | page 22 / 31 www. hoperf .com 5.9.2 matrix the matrix button mode is supported in 1920 and 1527 format. in t he matrix button mode, the number of buttons is fixed at 5. on the rfpdk, it can be seen that the 5 buttons are assigned to pin 11 (k1) ? pin 7 (k5). in this mode, at most two buttons can be pressed at the same time. t he figure below gives an example of matrix mode push button arrangement. led vdd gnd rfo k7 k6 k5 xtal clk k0 k1 k2 k3 k4 b0 b1 b2 b3 nc b4 nc nc led vdd gnd rfo clk xtal 7 6 5 1 2 3 4 8 9 10 14 13 12 11 figure 24 . matrix button mode the user is able to use the 5 buttons k1 (b0) ? k5 (b4) to generate di fferent combinations of the data d0 ? d3 to be transmitted. the number of data bits to be transmitted is fixed at 4. the table below shows the matrix. for the k1 ? k5 buttons, ?1? in the push buttons section means the corresponding button(s) is/are pressed down , w hile the ?1? in the data bits section means a logic ?1? to be transmitted. . table 17. mapping from k1 - k5 to d0 - d3 in matrix button mode push buttons the data bits k1 k2 k3 k4 k5 d0 d1 d2 d3 1 0 0 0 0 1 0 0 0 0 1 0 0 0 0 1 0 0 0 0 1 0 0 1 1 0 0 0 0 0 1 0 0 0 1 0 0 0 0 0 1 1 0 1 0 1 1 0 0 0 0 1 1 0 1 0 1 0 0 1 1 1 0 1 0 0 1 0 0 0 0 1 1 0 0 0 1 1 0 0 1 0 1 1 0 0 0 1 0 1 0 1 0 1 0 1 1 0 1 0 1 0 0 1 0 0 1 1 0 0 1 1 0 1 0 1 1 0 0 1 0 1 0 1 1 1 0 0 0 1 1 1 1 1 1
cmt21 57a w rev 0.8 | page 23 / 31 www. hoperf .com 5.9.3 toggle the toggle button mode is supported in 1920 and 1527. in this mode, 5 or 6 buttons are used. four buttons directly mapped to the data d0 ? d3 are used to control the data. besides, a single button or two separated buttons used to turn on/off the data can b e chosen by the parameter ? on/off button(s) ? . in this mode, only one button can be pressed at the same time. pin 12 (k0) and pin 5 (k7) are never used in this mode. t he figure below gives examples of the pin functions in toggle mode. led vdd gnd rfo k7 k6 k5 xtal clk k0 k1 k2 k3 k4 nc on off d0 d1 d2 d3 nc led vdd gnd rfo clk xtal 7 6 5 1 2 3 4 8 9 10 14 13 12 11 led vdd gnd rfo k7 k6 k5 xtal clk k0 k1 k2 k3 k4 nc on/off nc d0 d1 d2 d3 nc led vdd gnd rfo clk xtal 7 6 5 1 2 3 4 8 9 10 14 13 12 11 figure 25 . toggle button mode with single (left) and separated (right) on/off button(s) for the 4 data buttons mapped to d0 ? d3, every time a button is pressed, the generated data bit toggles. for examp le, if the default value of d1 is 0, press k4 down, the d1 is set to 1 in the current transmission, release the k4 and press it down again, the d1 is set to 0 in the current transmission, and so on. this is what it means by ? toggle ? . s ee the table below for the examples of toggle button mode table 18. examples of the toggle button mode on/off button(s) pressed button (times) d0 d1 d2 d3 single (k1 is on/off) press k4 (d1) ? 1 st time 0 1 0 0 press k4 (d1) ? 2 nd time 0 0 0 0 press k4 (d1) ? 3 rd time 0 1 0 0 press k1 ? 1 st time (on) 1 1 1 1 press k1 ? 2 nd time (off) 0 0 0 0 press k1 ? 3 rd time (on) 1 1 1 1 separated (k1 is on k2 is off) press k4 (d1) ? 1 st time 0 1 0 0 press k4 (d1) ? 2 nd time 0 0 0 0 press k4 (d1) ? 3 rd time 0 1 0 0 press k1 (on) 1 1 1 1 press k2 (off) 0 0 0 0 press k1 (on) 1 1 1 1 5.9.4 pwm the pwm button mode is only supported for 1920 and 1527 encod ing format . in this mode, 2 buttons are used to send out commands to increase or decrease the duty ratio of the pwm output of the cmt2251 aw . a single on/off button, or two separated on/off buttons can be chosen by the parameter ? on/off button(s) ? . the ? on ? command sets the pwm output of the cmt2251 aw to 100% of duty ratio, while the ? off ? command sets the pwm output to 0% of duty ratio. in this mode, only one button can be pressed at the same time. pin 12 (k0), pin 9 (k3), pin 6 (k6) and pin 5 (k7) are never used in this mode. the commands of on, off, increase and decrease are represented by d0 ? d3 . t he figure below gives examples of the pin
cmt21 57a w rev 0.8 | page 24 / 31 www. hoperf .com functions in pwm mode. led vdd gnd rfo k7 k6 k5 xtal clk k0 k1 k2 k3 k4 nc on/off nc nc inc dec nc nc led vdd gnd rfo clk xtal 7 6 5 1 2 3 4 8 9 10 14 13 12 11 led vdd gnd rfo k7 k6 k5 xtal clk k0 k1 k2 k3 k4 nc on/off off nc inc dec nc nc led vdd gnd rfo clk xtal 7 6 5 1 2 3 4 8 9 10 14 13 12 11 figure 26 . pwm button mode with single (left) and separated (right) on/off button(s) if k1 is used as the on/off button, press it down once, the ? on ? command is transmitted, release and press it down again, the ? off ? command is transmitted, and so on. in this case, k1 is a ? toggle ? button. if the k1 is used as the on button and k2 is used as the off button, pressing k1, the ? on ? command is transmitted; pressing k2, the ? off ? command is transmitted. 5.10 led driving capability this define s the maximum current driving capacity on the led pin. once the led pin is enabled, it will light up or flash to indicate two events : ? when the chip is transmitting data, the led will light up until the transmission is finished to notif y the user the chip is working , when the lbd is disabled , or lbd is enabled but there is no low battery detected. ? when the lbd is enabled and there is valid low battery detection on the button(s) pressing, the led will flash at least 5 times at the frequency of 6 hz to notify the user the battery is running out. 5.11 l ow battery detection (lbd) this defines the low battery detection threshold. once the lbd is enabled, the chip will automatically check the battery stat us before each transmission. once the chip finds that the battery output is less than the detection threshold, the led will flash at least 5 times at the frequency of 6 hz to notify the user. once the led flashes, the performance of the transmission is not guaranteed . the user should change the batteries to new ones. 5.12 crystal oscillator and rclk t he cmt2157 aw uses a 1 - pin crystal oscillator circuit with the required crystal load capacitance integrated on - chip . figure 27 shows the configuration of the xtal circuitry and the crystal model. the recommended specification for the crystal is 26 mhz with 20 ppm, esr (rm) < ordgfdsdflwdqfh& lo ad ranging from 12 to 20 pf. to save the external load capacitors, a set of variable load capacitors c l is built in side the cmt2157 aw to support the oscillation of the crystal . t he value of load capacitors is configurable with the cmostek usb programmer and rfpdk. to achieve the best performance, the user only needs to input the desired value of the xtal load capacitance c load of the crystal (can be found in the datasheet of the crystal) to the rfpdk , then fine ly tune the required xo load capacitance according to t he actual xo frequency. please refer to ? an1 1 3 cmt2157a / 2250 (1) a one - way rf link development kits user?s guide? f or the method of choosing the right value of c l .
cmt21 57a w rev 0.8 | page 25 / 31 www. hoperf .com cmt2157aw xtal crystal model rm cm c l c0 lm cmt 2157 aw xtal c l rclk 26 mhz cc 0 . 3 C 0 . 7 vpp if a 26 mhz rclk (reference clock) is available in the system, the user can directly use it to drive the cmt2157 aw by feed ing the clock into the chip via the xtal pin. this further sav es the system cost due to the removal of the crystal. a coupling capacitor is required if the rclk is used. the recommended amplitude of the rclk is 0.3 to 0.7 vpp on the xtal pin. also, the user should set the internal load capacitor c l to its minimum value. see figure 28 for the rclk circuitry . figure 28 . rclk circuitry figure 27 . xtal circuitry and crystal model
cmt21 57a w rev 0.8 | page 26 / 31 www. hoperf .com 6. ordering information table 19. cmt2157 aw ordering information part number descriptions package type package option operating condition moq / multiple cmt2157 aw - esr [1] 240 ? 960 mhz (g)fsk/ook stand - alone transmitter with encoder so p14 tape & reel 1.8 to 3.6 v, - 40 to 85 2 , 5 00 cmt2157 aw - esb [1] 240 ? 960 mhz (g)fsk/ook stand - alone transmitter with encoder so p14 tube 1.8 to 3.6 v, - 40 to 85 1,000 note : [1]. ?e? stands for extended industrial product grade, which supports the temperature range from - 40 to +85 . ?s? stands for the package type of so p14 . ?r? stands for the tape and reel package option, the minimum order quantity (moq) for this option is 2 , 5 00 pcs. ? b ? stands for the tube package option, with the moq of 1,000 pcs. t he default frequency for cmt2157 aw is 868.35 mhz, for the other settings, please refer to the table 10 of page 13. visit www.cmostek.com/products to know more about the product and product line. contact sales@cmostek.com or your local sales representatives for more information.
cmt21 57a w rev 0.8 | page 27 / 31 www. hoperf .com 7. package outline c h 0.25 l l1 a1 a3 a2 a d b e e1 e figure 29 . 14 - pin s op package table 20. 14- pin so p package dimensions symbol size (millimeters) min typ max a - - 1.75 a1 0.05 - 0.225 a2 1.30 1.40 1.50 a3 0.60 0.65 0.70 b 0.39 - 0.48 c 0.21 - 0.26 d 8.45 8.65 8.85 e 5.80 6.00 6.20 e1 3.70 3.90 4.10 e 1.27 bsc h 0.25 - 0.50 l 0.30 - 0.60 l1 1.05 bsc 0 - 8
cmt21 57a w rev 0.8 | page 28 / 31 www. hoperf .com 8. top marking 8.1 cmt2157 aw top marking c m t 2 1 5 7 a y y w w figure 30 . cmt2157 aw top marking table 21. cmt2157 aw top marking explanation mark method : laser pin 1 mark : circle?s diameter = 1 mm font size : 0. 35 mm, right - justified line 1 marking : cmt2157 a , represents part number cmt2157 aw line 2 marking : yyww is the date code assigned by the assembly house. yy represents the last two digits of the mold year and ww represents the workweek ????? is the internal tracking number
cmt21 57a w rev 0.8 | page 29 / 31 www. hoperf .com 9. other documentations table 22 . other d ocumentations for cmt2157 aw brief name description s an1 1 1 cmt215 x schematic and pcb layout design guideline detail s of cmt215 0/5 7 aw pcb schematic and layout design rules, rf matching network and other application layout design related issues. an1 4 2 cmt2157a configuration guideline detail s of configuring cmt2157 aw features on the rfpdk. an 1 1 3 cmt2157a /22 5 0 (1) a one - way rf link development kits user?s guide user ? s guides for cmt2157 aw /22 5 0 (1) aw development kits, including evaluation board and evaluation module , cmostek usb programmer and rfpdk. an115 pairing cmt21 5x and cmt225 x provide quick guideline in how to pair the cmt215 0/57 aw with cmt2250 /51 aw .
cmt21 57a w rev 0.8 | page 30 / 31 www. hoperf .com 10. document change list table 23. document change list rev. no. chapter description of changes date 0.8 a ll initial released version 2015 - 02- 11
cmt21 57a w rev 0.8 | page 31 / 31 www. hoperf .com 11. contact information hope microelectronics co., ltd address: 2/f,building3,pingshan private enterprise science and technology park,xili town,nanshan district,shenzhen,china tel: +86 - 755 - 82973805 fax: +86 - 755- 82973550 email: sales@hoperf.com hoperf@gmail.com website: http://www.hoperf.com http://www.hoperf.cn the information furnished by cmostek is believed to be accurate and reliable. however, no responsibility is assumed for inaccuracies and specifications within this document are subject to change without notice. the material contained herein is the exclusive property of cmostek and shall not be d istributed, reproduced, or disclosed in whole or in part without prior written permission of cmostek. cmostek products are not authorized for use as critical components in life support devices or systems without express written approval of cmostek. the cmo stek logo is a registered trademark of cmostek microelectronics co., ltd. all other names are the property of their respective owners. copyright. cmostek microelectronics co., ltd. all rights are reserved.

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