? semiconductor components industries, llc, 2005 august, 2005 ? rev. 2 1 publication order number: NB2779A/d NB2779A low power, reduced emi clock synthesizer the NB2779A is a versatile spread spectrum frequency modulator designed specifically for a wide range of clock frequencies. the NB2779A reduces electromagnetic interference (emi) at the clock source, allowing system wide reduction of emi of all clock dependent signals. the NB2779A allows significant system cost savings by reducing the number of circuit board layers, ferrite beads and shielding that are traditionally required to pass emi regulations. the NB2779A uses the most efficient and optimized modulation profile approved by the fcc and is implemented by using a proprietary all digital method. the NB2779A modulates the output of a single pll in order to ?spread? the bandwidth of a synthesized clock, and more importantly, decreases the peak amplitudes of its harmonics. this results in significantly lower system emi compared to the typical narrow band signal produced by oscillators an d most frequency generators. lowering emi by increasing a signal?s bandwidth is called ?spread spectrum clock generation?. the NB2779A is targeted towards all portable devices with very low power requirements like mp3 players and digital still cameras. features ? generates an emi optimized clocking signal at the output ? integrated loop filter components ? operates with a 3.3 v / 2.5 v supply ? operating current less than 4.0 ma ? low power cmos design ? input frequency range: 13 mhz to 30 mhz for both voltages ? generates a 1x low emi spread spectrum clock of the input frequency ? frequency deviation 1% @ 16 mhz ? available in tsop?6 package (tsot?23?6) ? pb?free package is available marking diagram* *for additional marking information, refer to application note and8002/d. tsop?6 (tsot?23?6) sn suffix case 318g see detailed ordering and shipping information in the package dimensions section on page 7 of this data sheet. ordering information http://onsemi.com 1 e06 = specific device code a =assembly location y = year w = work week e06ayw 1 6
NB2779A http://onsemi.com 2 figure 1. block diagram modout crystal oscillator frequency divider feedback divider phase detector loop filter xin/clkin xout modulation v dd v co output divider pll v ss pd table 1. key specifications description specification supply voltages v dd = 3.3 v / 2.5 v frequency range for 2.5 v supply for 3.3 v supply 13 mhz < clkin < 30 mhz 13 mhz < clkin < 30 mhz cycle?to?cycle jitter 200 ps (maximum) output duty cycle 45/55% (worst case) modulation rate equation f in /640 frequency deviation 1% (typ) @ 16 mhz v dd 1 2 3 6 5 4 xout xin/clkin modout NB2779A v ss pd figure 2. pin configuration table 2. pin description pin # pin name type description 1 pd i powerdown control pin. pull low to enable powerdown mode. connect to v dd if not used. 2 xout o crystal connection. if using an external reference, this pin must be left unconnected. 3 xin/clkin i crystal connection or external reference frequency input. this pin has dual functions. it can be connected either to an external crystal or an external reference clock. 4 v dd p power supply for the entire chip. 5 modout o spread spectrum clock output. 6 v ss p ground connection.
NB2779A http://onsemi.com 3 figure 3. modulation profile table 3. maximum ratings symbol description rating unit v dd, v in voltage on any pin with respect to ground 0.5 to +7.0 v t stg storage temperature ?65 to +125 c t a operating temperature 0 to 70 c t s max. soldering temperature (10 sec) 260 c t j junction temperature 150 c t dv static discharge voltage (as per mil?std?883, method 3015) 2 kv maximum ratings are those values beyond which device damage can occur. maximum ratings applied to the device are individual str ess limit values (not normal operating conditions) and are not valid simultaneously. if these limits are exceeded, device functional operation i s not implied, damage may occur and reliability may be affected.
NB2779A http://onsemi.com 4 table 4. dc electrical characteristics for 2.5 v supply (test conditions: all parameters are measured at room temperature 25 c) symbol description min typ max unit v il input low voltage gnd ? 0.3 0.8 v v ih input high voltage 2.0 v dd + 0.3 v i il input low current ?35 a i ih input high current 35 a i xol xout output low current (@ 0.5 v, v dd = 2.5 v) 3.0 ma i xoh xout output high current (@ 1.8 v, v dd = 2.5 v) 3.0 ma v ol output low voltage (v dd = 2.5 v, i ol = 8.0 ma) 0.6 v v oh output high voltage (v dd = 2.5 v, i oh = 8.0 ma) 1.8 v i dd static supply current (note 1) 10 a i cc dynamic supply current (2.5 v, 16 mhz, and no load) 3.0 ma v dd operating voltage 2.375 2.5 2.625 v t on powerup time (first locked cycle after powerup) (note 2) 5.0 ms z out clock output impedance 50 note: device will meet the specifications after thermal equilibrium has been established when mounted in a test socket or printe d circuit board with maintained transverse airflow greater than 500 lfpm. electrical parameters are guaranteed only over the declared operating temperature range. functional operation of the device exceeding these conditions is not implied. device specification limit values are applied individually under normal operating conditions and not valid simultaneously. 1. xin/clkin pin and pd are pulled low. 2. v dd and xin/clkin input are stable, pd pin is made high from low. table 5. ac electrical characteristics for 2.5 v supply symbol description min typ max unit clkin input frequency 13 30 mhz modout output frequency 13 30 mhz f d frequency input frequency = 13 mhz input frequency = 30 mhz 1.15 0.6 mhz t lh (note 3) output rise time (measured at 0.7 v to 1.7 v) 0.7 1.4 1.8 ns t hl (note 3) output fall time (measured at 1.7 v to 0.7 v) 0.4 0.9 1.1 ns t jc jitter (cycle?to?cycle) 200 ps t d output duty cycle 45 50 55 % note: device will meet the specifications after thermal equilibrium has been established when mounted in a test socket or printe d circuit board with maintained transverse airflow greater than 500 lfpm. electrical parameters are guaranteed only over the declared operating temperature range. functional operation of the device exceeding these conditions is not implied. device specification limit values are applied individually under normal operating conditions and not valid simultaneously. 3. t lh and t hl are measured at capacitive load of 15 pf.
NB2779A http://onsemi.com 5 table 6. dc electrical characteristics for 3.3 v supply (test conditions: all parameters are measured at room temperature 25 c) symbol description min typ max unit v il input low voltage gnd ? 0.3 0.8 v v ih input high voltage 2.0 v dd + 0.3 v i il input low current ?35 a i ih input high current 35 a i xol xout output low current (@ 0.4 v, v dd = 3.3 v) 3.0 ma i xoh xout output high current (@ 2.5 v, v dd = 3.3 v) 3.0 ma v ol output low voltage (v dd = 3.3 v, i ol = 8.0 ma) 0.4 v v oh output high voltage (v dd = 3.3 v, i oh = 8.0 ma) 2.5 v i dd static supply current (note 4) 10 a i cc dynamic supply current (3.3 v, 16 mhz, and no load) 3.5 ma v dd operating voltage 2.7 3.3 3.6 v t on powerup time (first locked cycle after powerup) (note 5) 5.0 ms z out clock output impedance 45 note: device will meet the specifications after thermal equilibrium has been established when mounted in a test socket or printe d circuit board with maintained transverse airflow greater than 500 lfpm. electrical parameters are guaranteed only over the declared operating temperature range. functional operation of the device exceeding these conditions is not implied. device specification limit values are applied individually under normal operating conditions and not valid simultaneously. 4. xin/clkin pin and pd are pulled low. 5. v dd and xin/clkin input are stable, pd pin is made high from low. table 7. ac electrical characteristics for 3.3 v supply symbol description min typ max unit clkin input frequency 13 30 mhz modout output frequency 13 30 mhz f d frequency input frequency = 13 mhz input frequency = 30 mhz 1.15 0.6 mhz t lh (note 6) output rise time (measured at 0.8 v to 2.0 v) 0.5 1.1 1.3 ns t hl (note 6) output fall time (measured at 2.0 v to 0.8 v) 0.3 0.8 0.9 ns t jc jitter (cycle?to?cycle) 200 ps t d output duty cycle 45 50 55 % note: device will meet the specifications after thermal equilibrium has been established when mounted in a test socket or printe d circuit board with maintained transverse airflow greater than 500 lfpm. electrical parameters are guaranteed only over the declared operating temperature range. functional operation of the device exceeding these conditions is not implied. device specification limit values are applied individually under normal operating conditions and not valid simultaneously. 6. t lh and t hl are measured at capacitive load of 15 pf.
NB2779A http://onsemi.com 6 figure 4. typical crystal oscillator circuit crystal c1 = 27 pf c2 = 27 pf r1 = 510 table 8. typical crystal specifications fundamental at cut parallel resonant crystal nominal frequency 14.31818 mhz frequency tolerance 50 ppm or better at 25 c operating temperature range ?25 c to +85 c storage temperature ?40 c to +85 c load capacitance 18 pf shunt capacitance 7 pf maximum esr 25
NB2779A http://onsemi.com 7 ordering information device marking temperature range package shipping ? availability NB2779Asnr2 e06 0 c ? 70 c tsop?6 (tsot?23?6) 2500 tape & reel now NB2779Asnr2g e06 0 c ? 70 c tsop?6 (tsot?23?6) (pb?free) 2500 tape & reel contact sales representative ?for information on tape and reel specifications, including part orientation and tape sizes, please refer to our tape and reel packaging specifications brochure, brd8011/d.
NB2779A http://onsemi.com 8 package dimensions tsop?6 (tsot?23?6 ) case 318g?02 issue n 23 4 5 6 a l 1 s g d b h c 0.05 (0.002) dim min max min max inches millimeters a 0.1142 0.1220 2.90 3.10 b 0.0512 0.0669 1.30 1.70 c 0.0354 0.0433 0.90 1.10 d 0.0098 0.0197 0.25 0.50 g 0.0335 0.0413 0.85 1.05 h 0.0005 0.0040 0.013 0.100 j 0.0040 0.0102 0.10 0.26 k 0.0079 0.0236 0.20 0.60 l 0.0493 0.0610 1.25 1.55 m 0 10 0 10 s 0.0985 0.1181 2.50 3.00 notes: 1. dimensioning and tolerancing per ansi y14.5m, 1982. 2. controlling dimension: millimeter. 3. maximum lead thickness includes lead finish thickness. minimum lead thickness is the minimum thickness of base material. 4. dimensions a and b do not include mold flash, protrusions, or gate burrs. m j k 0.95 0.037 1.9 0.075 0.95 0.037 mm inches scale 10:1 1.0 0.039 2.4 0.094 0.7 0.028 *for additional information on our pb?free strategy and soldering details, please download the on semiconductor soldering and mounting techniques reference manual, solderrm/d. soldering footprint* on semiconductor and are registered trademarks of semiconductor components industries, llc (scillc). scillc reserves the right to mak e changes without further notice to any products herein. scillc makes no warranty, r epresentation or guarantee regarding the suitability of its products for an y particular purpose, nor does scillc assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including wi thout limitation special, consequential or incidental damages. ?typical? parameters which may be provided in scillc data sheets and/or specifications can and do vary in different application s and actual performance may vary over time. all operating parameters, including ?typicals? must be validated for each customer application by customer?s technical experts. scillc does not convey any license under its patent rights nor the rights of others. scillc products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the scillc product could create a sit uation where personal injury or death may occur. should buyer purchase or use scillc products for any such unintended or unauthorized application, buyer shall indemnify and hold scillc and its of ficers, employees, subsidiaries, af filiates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, direct ly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that scillc was negligent regarding the design or manufacture of the part. scillc is an equal opportunity/affirmative action employer. this literature is subject to all applicable copyright laws and is not for resale in any manner. publication ordering information n. american technical support : 800?282?9855 toll free usa/canada japan : on semiconductor, japan customer focus center 2?9?1 kamimeguro, meguro?ku, tokyo, japan 153?0051 phone : 81?3?5773?3850 NB2779A/d this product utilizes us patent #6,646,463 impedance emulator patent issued to alliance semiconductor, dated 11?11?2003. literature fulfillment : literature distribution center for on semiconductor p.o. box 61312, phoenix, arizona 85082?1312 usa phone : 480?829?7710 or 800?344?3860 toll free usa/canada fax : 480?829?7709 or 800?344?3867 toll free usa/canada email : orderlit@onsemi.com on semiconductor website : http://onsemi.com order literature : http://www.onsemi.com/litorder for additional information, please contact your local sales representative.
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