View AN488_5769873.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

application note phone remote system AN488/0695 by jo?l huloux, patrice morel contents page i introduction .................................... ................... 2 i.1 general purpose. . . . . . . . . . . . . . . . ................................... 2 i.2 description . . . . . ................................................... 2 i.3 improvements...................................................... 2 ii power line communication using st7537cfn ........................ 2 ii.1 c.s.m.a. timings . . ................................................... 2 ii.2 soft carrier detector. . . . . . ....................... ................ 4 ii.3 implementationonst6265 .......................................... 5 iii phone remote system .............................................. 6 iii.1 general description . . . . . . . . . . . . . . . . . . . . . . . . . . . . ................... 6 iii.2 telephone line interface . . . . . . . . . . . . . ............................. 8 iii.2.1 isolation. . . . . . . . . . . . . . . . . . . . . . . ....................... ................ 8 iii.2.2 input impedance . . . . ................................................... 9 iii.2.3 current regulation . . . . . . . . . . . . . . ....................................... 9 iii.2.4 hook-off procedure . . . . . . . . . . . . ......................................... 9 iii.3 mains flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ................... 10 iii.4 application procedure. . . . ......................................... 12 iii.4.1 installation . . . ......................................................... 12 iii.4.2 description . ................. ......................................... 12 iii.4.3 use . . . . . . . . . . . . . . . . . ............................. ................... 12 iv conclusion ..................................... ................... 13 v annexe 1 : bill of materials . . . . . . . . . . . . . . . . . . . . . ................... 14 vi annexe 2 : schematics . .......................... ................... 15 1/16
i - introduction i.1 - general purpose in the application note an535, we described how to implement the basis of a power line network using the dedicatedmodem chip st7537cfn. this network has been validated with st7537 master & slave systems, and shows the feasibility of power line control. but home automation systems allow more than switching a light, or changing the value of a digit. the possibilities of the network increase each time we connect a new device on it. for instance, adding a phone remote system will allow the remote (from anywhere on the planet) control of devices connected on the network only by calling your house. the phone remote system is now demonstrating this fact : a telephone interface that allows the householder to give instructions to appliances from outside. i.2 - description the phone remote system is a device connected to both telephone line and power line network. it is able to detect the phone ring, to hang up the line, and oconverseo with the householder. this dialogue is done by using the dtmf (digital tone multi- frequency) generated by the remote phone. to answer back, the phone remote system is beeping. of course, this is a low cost choice and the system can be improved by using a voice synthesiser with on line help and so on... phone remote system remote object 2 mains telephone line remote object 1 AN488-01.eps figure 1 : phone remote system connected to the power line network in a classical electric installation, this device would have used one control cable for each controlled object. with power line control, you just have to plug it and the link is done with all devices controlled by mains network. i.3 - improvements the part ii describes several improvements done to the communication program explained in an535.these modifications allow new features : - software carrier detect, - c.s.m.a. timings (carrier sense multiple access), and the use of communication modules in phone remote program. ii - power line communication using st7537cfn the st7537 cfn power line modem complies with the regulation described in the cenelec en50.065-.1 document, (so frequency, bit coding and other useful features are included in the chip). nevertheless, the designer of an application has to take in account the power line communication specification when writing his protocol. for in- stance, access protocols are required for coexis- tence on the medium. ii.1 - c.s.m.a. timings the following paragraphs give a concrete case of communication on power line network. in first, only 2 devices are connected to the network. then, others devices are connected, and we will be con- fronted to a real network specification. communication between 2 units this is the simplest case of communication. only two devices are able to send and receive packet on the network. one unit sends an order, the other one is replying with an acknowledge (see figure 2). the unit t checks that the network is free for access thanks to the carrier detector, then it sends its frame and waits an acknowledge during a delay twack. the unit r receive a frame and sends an acknowledge if r is the destination of the frame. r must send the ack. frame before the end of twack. if it is not the case, or if t has not received the acknowledge, t tries again to send the order. of course the frame format must allows error detec- tion by the receiver (order checksum) an by the transmitter (checksum in ack. frame). in most of the case, communication occurs without error, and the both units must keep silent for a delay tsilent in order to leave time for application control. to allow the two units to transmit, the unit t has to wait more than r, so r will be the first to take the channel if it needs to transmit. if the two units send a frame exactly at the same time, they will not receive ack. frame, so they will retry after a delay (twack). arandom value is added st7537 plm com. unit t unit r order frame ack. frame mains st7537 plm com. AN488-02.eps figure 2 : two units on the mains phone remote system application note 2/16
message message to u2 tretans twack u3 wants to transmit u4 wants to transmit tsilent (priority) message to u5 tsilent (priority) tsilent (priority) ack. ack. message u1 u2 u3 u4 u5 AN488-04.eps figure 4 : power line communication data timing to make one of the two unit faster than the other one. the total delay is tretrans. communication with several units st7537 plm com. unit 4 unit 1 order frame ack. frame mains 50/60hz st7537 plm com. st7537 plm com. unit 3 st7537 plm com. unit 2 AN488-03.eps figure 3 : several units on the mains with several units, the timing is the same, but even if a unit is not concerned with a communication, it has to get the frames in account for timing control. for instance, it has to reload its time to keep silent. and if several units have reload there time to keep silent at the end of a communication, the values reloaded must be different to avoid conflicts on the next communication. again, a random value is added to make timing different. here is a data timing chart of the transmitted signal of the different units (see figure 4). anyway, all units must send there message in less than two seconds. timing control all these timing are resumed in the table 1. table 1 : c.s.m.a. timing symbol description time comment tmax total duration of transmission 2s maximum duration of transmission after starting 1s feature included in st7537cfn tsilentr length to wait from the end of a remote transmission to initiate a transmission 85 .. 125ms al least 7 values twack acknowledge sent after 0 .. 30ms tretransmit retry transmitting 30 .. 72ms tsilentt duration between two transmissions of the same device 125ms phone remote system application note 3/16
in order to implement these timing, an easy way is to use a single timer and several registers corre- sponding to the different delays you want to count. the timer will decrease the registers at each over- flow, and the counters are olaunchedo by loading a value in the corresponding register. this access protocol allows an additional network priority: if you allow unit 1 (u1) to transmit before unit 2 (u2), then u1 will always sends its messages before u2, and so will have a highest network priority. by choosing the range of tsilentr of a unit, you will then choose its priority. table 2 : priority according to tsilentr range priority 85 .. 94ms highest priority 95 .. 104ms standard priority 105 .. 115ms lowest priority ii.2 - soft carrier detector we have seen that by programming the txd to o0o in receive mode we increase the sensitivity of the st7537 because there is no more clamping by cd. you will be able to have good communication with a receive signal of around 50db m v which means a dynamic of around 70db. becausewe want to get the benefit of the very good sensitivity of the st7537 , we will program txd to o0o in receive mode and create by soft a frame detector . we will use the cd signal as mentioned by cenelec only when we want to transmit a frame . different software frame detectors can be implemented depending of the resources of your microcontroller. you can program your microcon- rxd frame random datas data ffh o1o AN488-06.eps figure 6 : preamble detector rxd preamble expected byte frame random datas AN488-05.eps figure 5 : rxd data timing troller to go in receive frame when it received the expected byte. so the preamble is for demodulator training (when you start a communication the 3 first bits are lost by the receiver) and when you will match with expected byte the micro-controller will go in receive frame routine. on the st6 microcontroller we have implemented the following frame detector. we put txd = o 1o on the transmitter for around 4ms (for demodulator training) and after we send in asynchronousmode ffh following by the complete frame. on the receiver , we check that we have rxd equal to o1o for at least 7ms (we are looking for ffh), then we go in receive and we will have frame synchronisation on the first start bit of the data. we did a trial in our lab with this system during 2 hours without having the st6 going in frame re- ceive routine on bad datas due to noise signal. phone remote system application note 4/16
ii.3- implementation on st6265 the c.s.m.a. (carrier sense multiple access) needs a timer for its implementation. but the st6265 timer 1 is already used for bit time and software carrier detect. furthermore, sometimes the timer has several functions at the same time, so the timer programming becomes very compli- cated. in order to simplify this programming, we have implemented a single time delay corresponding to bit time (f = 1200hz). so for each mode there is a counter corresponding to a delay. the counters are incremented (or decremented) in the timer interrupt routine while they are cleared (or affected with values) in main program. for c.s.m.a. specifica- tions, we use two counters : - xmit_count : this is the delay before retransmit- ting, - rmit_count : this is the delay before transmitting after a reception. these counters are decremented in timer 1 inter- rupt routine and flags are set when they become null. these flags are allowing the sending of a frame. acknowledge frames are not concerned with these timing. the timer will allow the sending of a frame after c.s.m.a. delays (see figure 7). with this way of programming, the places where counters are loaded are very significant (see fig- ure 8) : - xmit_count is loaded at the end of the message sending procedure in order to wait an acknow- ledge (30ms) and at the end of the reception of a good acknowledge (time between two transmis- sions of the same device : 125ms), - rmit_count is loaded at the end of a reception with a random value (time between two transmis- sion of different devices : 85 to 115ms). send_fram receipt_flag set ? xmit_flag set ? rmit_flag set ? send_tram ret no no no yes yes AN488-07.eps figure 7 : sending a frame after c.s.m.a. delays reti 6 xmit counter = 0 3 rxd high ? 8 rmit counter = 0 2 timer 1 4 inc soft cd counter 4 inc soft cd counter yes no 11 preamble detected yes 12 set receive flag 7 dec rmit counter yes yes no 9 set rmit flag 10 set xmit flag AN488-08.eps figure 8 : timer 1 flow chart phone remote system application note 5/16
iii - phone remote system iii.1 - general description the phone remote system is using the st7537cfn chip and its line interface for power line communi- cation (see figure 9). the control unit is st6265 microcontroller (sgs-thomson) that has several functions. the telephone interface is described in further detail in next paragraph. the mcu mains functions are : - detect a ring, - take the line and hang up, - decode dtmf code, - make some obeepo, - control the modem chip, - display its status (leds for instance). these functions are the minimum required to pro- telephone line mcu st5265 mains interface : p.l.m. communication with st7537cfn telephone interface AN488-09.eps figure 9 : block diagram c0 c1 c2 c3 c4 nmi res oso a7 a6 a5 a4 a3 osi a2 a1 v ss v dd a0 b7 b6 b5 b4 b3 b2 b1 b0 tes v cc %2 st7537cfn + power line interface rxd txd rx/tx rsto mclk /wd /cd st6265 sound generation hook-off ring detect dtmf decoder q1 q2 q3 q4 std push button AN488-10.eps figure 10 : st6265 application vide remote control. the figure 10 propose these functions. phone remote system application note 6/16
st7537 interface the st6265 is directly connected to st7537, ex- cepted the clock that must be divided by a factor 2 (st6265 is validated at 8mhz max. and st7537 provides a 11mhz clock signal). for further details, refer to an535. hook-off the hook-off system must be able to take the line. a relay connected to the two wires of the telephone line complies with all regulations. see telephone interface part for more information. hook-off line 2 line 1 line phone AN488-11.eps figure 11 : hook-off schematic line ring detect AN488-12.eps figure 12 : ring detect schematic AN488-13.tif figure 13 : ring detect signal & ring detect signal zoomed ring detect an opto-transistor is used to detect the ring signal on the line. so the system is isolated from the line and the microcontroller receive a 0 to 5v signal. for example, this is what appears on ring detect pin with a french standard line (see figure 13). the first line is the ring detect signal which is zoomed on the second line. on french lines, the ring is about 1.5 second and the silence is about 3.5 second. that means a ring period of 5 seconds. phone remote system application note 7/16
sound generation sound generation allows reply from the system. mcu just sends square signal that makes a beep. signal 1 sound generator v cc AN488-14.eps figure 14 : sound generation schematic dtmf decoder users send orders with dtmf code. these codes are decoded with a dtmf receiver lc7385 (sanyo). it is configured in single ended input. it has a dynamic range input of 29dbm. 1 2 3 4 5 6 7 8 9 10 16 17 18 11 12 13 14 15 signal 2 to mcu v cc v ss v ref v dd in+ in- gs b/h pd osc1 osc2 st/gt est std q4 q3 q2 q1 toe AN488-15.eps figure 15 : single ended input configuration tone #n dtmf input datas tone #n+1 decoded tone #n decoded tone #n+1 std t1 t2 t1 = 40ms t2 = 4.5 m s AN488-16.eps figure 16 : dtmf receiver timing diagram when receiving dtmf code, this ic chip is gener- ating the following signal (see figure 16). iii.2 - telephone line interface the line interface must verify regulation of system connected to telephone line, that's why it is de- scribed in detail here. line interface input imped- ance and current consumption has been adjusted. in the following schematic, the transformer accept continuous current and current consumption is done by a resistor and a capacitor in parallel. relay ri signal 1 signal 2 w1 AN488-17.eps figure 17 : telephone line interface iii.2.1- isolation as the phone remote system is connected to the telephone line, it must be isolated from high volt- ages that may occurs on it. there are two connec- tions to the line : - the ring detect interface is isolated with an opto- transistor, - the dtmf & sound generation interface isolation is made by a transformer and a voltage limitation by zener diodes. furthermore, a transil diode between the two line wires limits the input voltage. phone remote system application note 8/16
iii.2.2 - input impedance the input impedance has been adjusted by chang- ing ri value (see figure 17) with a wheastone's bridge method explained in the figure 18. e is generated by a hp3325b generator and u is read on a fluke 45 controller. we made e scanning frequency from 300 to 4000hz. the maximum values for u are shown in the table 3. table 3 : error voltage versus ri ri ( w ) u (mv) ri ( w ) u (mv) ri ( w ) u (mv) 200 69 325 40 400 47 275 44 350 41 500 63 300 40 375 45 600 75 ri has been fixed at 300 w . that mean an adapting coefficient (alpha) : alpha = 20 log 1 2 ? 0.04 = 21dbm french standard specifies a value superior to 14dbm. v e u r rr phone remote system r=600 w e = 1000mv alpha = 20 log e 2u AN488-18.eps figure 18 : wheastone bridge 80 70 60 50 40 30 200 300 400 500 600 u(mv) r( w ) AN488-19.eps figure 19 : error voltage versus ri iii.2.3 - current regulation line current regulation is not needed in several countries. for these countries, a strap allows to disable current regulation which is done by a ctp resistor. iii.2.4 - hook-off procedure when taking the line, the system must care of the ring train. if it takes the line when phone is ringing, the relay will switch a voltage superior to 70 volts. to avoid this, the best way is to wait a silence (no ring). the phone remote system is waiting the end of a ring to take the line, as shown in the figure 20. the first line is the relay command and the second line is the ring signal. AN488-20.tif figure 20 : hook-off between two rings phone remote system application note 9/16
iii.3 - mains flow the phone remote system has a very simple pro- gress. it only has to wait after a ring, count for a pre-defined number of rings, take the line, ask for a password, and then send the user's orders on the telephone call good password wait 3 rings hold the line password dialog bad password order(s) dialog hang-up reti hang-up AN488-21.eps figure 21 : phone program main flow power line network (see figure 21). for security reasons, the user has only three tries to enter his password. if this operation is success- ful, he is allowed to send orders, otherwise the system hangs up (see figures 22 and 23). set good_pswd flag password dialog enter first code enter second code enter third code enter fourth code ret yes good password ? third trie ? no AN488-22.eps figure 22 : password dialogue phone remote system application note 10/16
answer to user order(s) dialog get objet address get order time_out time_out ret phone order execute order send order AN488-23.eps figure 23 : orders dialogue phone remote system application note 11/16
iii.4 - application procedure this part describes installation and utilisation of the phone remote system. iii.4.1 - installation the phone remote system needs to be connected to the mains and to the telephone line. connecting to mains : before connecting the phone remote system to mains, verify that the selected voltage is the same as your mains installation. the default voltage is 220 volts/50hz. connecting to telephone line : the telephone line connector is a rj11 type. this connector is wired according to french specifica- tions. iii.4.2 - description the phone remote system owns several switches and leds that indicate status and allow the con- figuration of parameters as number of rings, confi- dential code, ... table 4 : parts description part description switch user for switch the device on/off mini switch user to select the delay before hook-off : 3 or 5 rings push button user to reinitialize the status leds (single push) or to reinitialze the protection code (3 seconds push) red led (l1) violation led (wrong code) green led (l3) hook-off led yellow led (l4) ring led orange led (l2) bad power line network address : no acknowledge iii.4.3 - use enter confidential code when calling the phone remote system, you have to wait three or five rings. then the system hooks off and beeps three times. you have twenty sec- onds to enter the confidential code by using your 1 1 : unused 2 : phone 3 : line 4 : line 5 : phone 6 : unused 23456 AN488-24.eps figure 24 : rj11 connector phone keyboard. only dtmf phones are sup- ported. the initial value of the code is 0000, but of course you can change it. if the code entered is the good one, you are allowed to give orders. other- wise, you have two other attempts. enter orders an order is an object address (two digits), an application number (one digit) and a value (one digit). after you have entered the objet address, you hear three beeps (or you have to retry). then you enter the application number, and you hear three more beeps. at last, you enter the application value. if you hear three beeps, that means the message has been sent and that an acknowledge has been received. then you are allowed to send an other order. address appli. number 2 digits 3 beeps 1 digit 3 beeps appli. value 1 digit 3 beeps AN488-25.eps figure 25 : address format the slave sytems have address values from 00 to15. for these systems the application number select the dimmer (number 1) or the digit (num- ber 2). the value is the number diplayed on the digit, or the light intensity. for instance : - o15,2,0o will display 0 on the slave system wich address is 15, - o13,1,9o will switch the light on slave system number 13 on. there are special orders for phone control : - if you enter o99,1o, then the system will beep you the confidential code. if the code is 3456, you will hear 3 beeps then four, then five and then six beeps, - if you enter o99,2o, and four digits, these four digits will be the new confidential code to use for further call. table 5 : allowed orders enter values action xx,y,z 00 xx 15 0 z 9 y = 1 light intensity = z y = 2 display value = z 99,1 beeps the confidential code 99,2,xxxx 0000 xxxx 9999 new value for confidential code phone remote system application note 12/16
local configuration the yellow led is lighting when othe phone is ringingo. after 3 or 5 rings (depending on mini- switch), the system takes the line, and the green led remains on during all the phone dialogue. if three bad codes are sent, the red led will switch on. if a power line communication error occurs, the orange led will light. the red and the orange led will be left on, so a single push on the push-button will switch these led off. if you push on the push-button for more than 3 sec- onds, the confidential code will be changed to 0000. the confidentialcode is stocked in eeprom and will remains even if you disconnect mains. iv - conclusion the phone remote system increases the facilities offered by your automation network. with this sys- tem you can send orders by using dtmf code. by using a memory phone or a pocket dialler, you would be able to send orders only by choosing the system you want to talk to. for instance, you push the button called oheating ono and the order is immediately sent to the heater. furthermore, you could select an other temperature for the heating system, or ask for the temperature in any room of your house. these improvements are possible by adding a voice generator (sgs-thomson has dedicated voice chips) and if temperature sensor and heater are connected to the network. the phone remote system detailed in this note has not all these facilities, but it is a very low cost applica- tion with only few components and low cost choice for mcu and phone interface. the st7537 is pro- viding the power line communication and a hard- ware watchdog, while leaving resources for a low cost microcontroller. phone remote system application note 13/16
v - annexe 1 : bill of materials designation value package bp1 bp bp c1 1mf capc4 c2 22pf capd4 c3 22pf capd4 c4 6.8nf capd4 c5 1 m f capc4 c6 100nf capd4 c7 100nf capd4 c8 100nf capd4 c9 100nf capd4 c10 2.2 m f capc4 c11 2.2 m f capc4 c12 100nf capd4 c13 10 m f capc4 c14 100nf capd4 c15 10 m f capc4 c16 1000 m f cap12 c17 100nf capd4 c18 100nf capd4 c19 1mf capc4 c20 10 m f capc4 c22 100nf capd4 c23 2.2mf capc4 c24 100nf capd4 c25 100nf capd4 c26 100nf capd4 c27 100nf capd4 c28 470nf capd4 d1 diode diode d2 diode transil d3 1n4004 didb8 d4 1n4004 didb8 d5 1n4004 didb8 d6 1n4004 didb8 d7 1n4148 dida8 d8 zen.4.7v dida8 d9 zen.4.7v dida8 d10 zen.15v dida8 d11 zen.15v dida8 g1 gemov gemov ic1 st7537 st7537 ic2 st62e65 st62e65 ic3 lm7805 bto220 ic4 74ls74 dil14 ic5 lm7810 bto220 ic6 lc6385 dil18 ic8 4n36 dil6 k1 relay_dpdt relay ld1 led led ld2 led led designation value package ld3 led_jaune led ld4 led_verte led p1 alim220v alim220v p2 rj11 rj11 q1 2n2222 bto922 q2 2n2222 bto922 q3 2n2907 bto5 q4 2n2222 bto922 q5 2n2907 bto5 q6 2n2907 bto5 q7 bc547 bto5 q8 bc547 bto5 r1 1m w res8 r2 1k w res8 r3 2.2 w res8 r4 2.2 w res8 r5 2.2 w res8 r6 47k w res8 r7 180 w res8 r8 1k w res8 r9 47k w res8 r10 2.2 w res8 r11 180 w res8 r12 2.2 w res8 r13 4.7k w res8 r14 4.7k w res8 r15 220 w res8 r16 220 w res8 r17 470 w 3w res14 r18 1.5k w 1w res12 r19 300 w res8 r20 100k w res8 r21 100k w res8 r22 560 w res8 r23 2.2k w res8 r24 4.7k w res8 r25 300k w res8 r26 220 w res8 r27 4.7k w res8 r28 10k w res8 r29 100k w res8 sw1 mini_dip smini sw2 commut commut sw3 mini_dip mini tr1 toko toko tr2 ui30x10.5 ui30x10.5 tr3 tr3 transfo cecla w2 strap_3pts strap xt1 crystal crystal xt2 3.57945mhz hc49u phone remote system application note 14/16
vi - annexe 2 : schematics 1 2 4 5 6 7 8 9 10 16 17 18 19 20 26 27 28 13 14 15 21 22 23 24 25 pa0 pa1 pa2 pa3 pa4 pa5 pa6 pa7 pb0 pb1 pb2 pb3 pb4 pb5 pb6 pb7 11 12 v dd v ss oscin oscout pc4 pc3 pc1 pc2 pc0 nm1 oaoao ic2 st62e65 9 8 q n- 10 12 11 13 d clk pr cl ic4b 74ls74 +5v +5v +5v c17 100nf 12 b7 b4 b3 b2 b1 b0 a3 a2 +5v +5v r16 220 w r15 220 w ld2 led ld1 led q n- d clk pr cl ic4a 74ls74 6 5 4 2 3 1 +5v 2 3 5 6 7 8 9 10 16 17 18 19 20 26 27 28 11 12 13 14 15 21 22 23 24 25 mclk wd/ rx/tx/ cd/ txd rxd rsto dv cc 1 vcm av ss dv ss xtal1 xtal2 test4 test3 test2 test1 pabc pabc/ at0 pafb ra1 av dd dv dd dem1 if0 txf1 ic1 st7537 r13 4.7k w sw1 mini dip r14 4.7k w bp1 bp 2 1 +5v 1 2 2 1 +5v 1 2 c18 100nf c20 10 m f c6 100nf ic4 2 1 2 1 c2 22pf 2 1 c3 22pf xt1 1 2 2 1 c10 2.2 m f c7 100nf c8 100nf 2 1 1 2 c11 2.2 m f c9 100nf +10v r8 1k w r2 1k w r12 2.2 w r11 180 w r9 47k w r10 2.2 w r4 2.2 w 2 1 3 3 1 2 3 1 2 2 1 3 q6 2n2907 q5 2n2907 q1 2n2222 q4 2n2222 r5 2.2 w r7 180 w 2 1 3 q3 2n2907 3 1 2 q2 2n2222 r6 47k w 2 1 c5 1 m f r3 2.2 w d1 1 2 2 1 c4 6.8nf npo 3 2 1 tr1 r1 1m w 4 6 12 c1 1mf mkt 12 c19 1mf mkt e 3 p 1 n 2 p1 1 2 3 p1a p1c p1b mini dip sw3 14 16 tr2 10 12 sw2 mains switch phase neutral ui30x10.5 1 3 5 7 1 2 3 4 110v 220v 110v d3 d4 d5 d6 4 x 1n4004 1 2 2 1 c16 1000 m f 25v c22 100nf 2 3 1 out in gnd ic5 lm7810 1 2 2 1 c13 10 m f 16v c12 100nf 2 3 1 out in gnd ic3 lm7805 +10v 1 2 2 1 c15 10 m f 16v c14 100nf +5v AN488-26.eps phone remote system application note 15/16
information furnished is believed to be accurate and reliable. however, sgs-thomson microelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. no licence is granted by implication or otherwise under any patent or patent rights of sgs-thomson microelectronics. specifications mentioned in this publication are subject to change without noti ce. this publication supersedes and replaces all information previously supplied. sgs-thomson microelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of sgs-thomson microelectronics. ? 1995 sgs-thomson microelectronics - all rights reserved purchase of i 2 c components of sgs-thomson microelectronics, conveys a license under the philips i 2 c patent. rights to use these components in a i 2 c system, is granted provided that the system confo rms to the i 2 c standard specifications as defined by philips. sgs-thomson microelectronics group of companies australia - brazil - china - france - germany - hong kong - italy - japan - korea - malaysia - malta - morocco the netherlands - singapore - spain - sweden - switzerland - taiwan - thailand - united kingdom - u.s.a. 1 2 5 6 7 8 9 10 16 17 18 13 14 15 11 12 v ss toe ic6 lc7386 c24 100nf 12 b4 b3 b2 b1 b0 r22 560 w ld4 led verte +5v 1 2 c25 100nf st/gt est std q1 q2 q3 q4 v dd 4 3 v ref in+ in- gs osc1 osc2 b/h pd r25 300k w r21 100k w r20 100k w 2 1 xt 2 3.57945mhz c2 6 100nf 12 +5v b7 +5 v 2 1 3 q7 bc547 r23 2.2k w 1 2 c27 100nf r24 4.7k w r19 300 w d8 z en.4.7v d9 zen.4. 7 v 1 1 2 2 2 13 4 tr3 transfo. cecla r18 1.5k w 1w c23 2.2mf 250v 12 r17 470 w 3w 2 1 g1 gemov 2 3 1 w2 p2a k1 +5v a2 3 2 1 q8 bc547 r26 220 w ld3 l ed j au ne d7 1n4148 r27 4.7k w 1 2 p2b p2c p2d d2 relaydpdt d1 0 zen. 15v 1 212 d11 zen. 1 5v r28 10k w c28 470nf 250v 12 1 2 4 5 ic8 4n36 r29 100k w +5v a3 5 2 3 4 phone line AN488-27.eps phone remote system application note 16/16

▲Up To Search▲

Price & Availability of AN488

	To Download AN488 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .