the SY89424V is a low-power phase locked loop (pll) based frequency synthesizer. the device is capable of generating up to 1ghz clock frequencies with a low-cost 10?5mhz external series-resonant quartz crystal. one can also use pecl differential clock signals to drive this device instead of the quartz crystal. operation of this chip is controlled by three select pins (s1, s2 and s3). s1 selects the divide ratio of 24 or 50 for the pll. s2 and s3 select the output frequency. there are two pull-down resistor pins (pdr 1 and pdr 2 ). each pin has an on-chip resistor that will control the output driver currents. when pdr 1 and pdr 2 pins are open, both outputs are normal open emitter pecl drivers. when pdr 1 and pdr 2 pins are shorted to the outputs, on-chip pull down currents of 25ma (40ma at 5v v cc ) are provided. both output drivers are capable of driving 20 ohm clock lines. an output enable (oe) pin is available and it can be high or left open for normal operation. when oe is low, a built-in disable timing synchronizer will force the fout output to low at the completion of the high clock cycle. the fout output remains high during that time. 5v/3.3v frequency synthesizer (60mhz to 1ghz) block diagram clockworks SY89424V final 3.3v and 5v power supply options up to 1ghz clock frequencies internal quartz reference oscillator driven by quartz crystal or pecl source low jitter pll design on-chip 20 ohm driver differential outputs with 600mv (min) swing optional pull-down resistors for ac-coupled outputs low power consumption external loop filter optimizes performance/cost available in 16-pin soic package features description fout fout xtal1 loop filter s1a xtal2 osc phase comp charge pump 24, 50 vco s2a s3a 1, 2, 3, 4 oe pdr1 pdr2 f1a f2a 1 rev.: g amendment: /0 issue date: may, 1998
2 clockworks SY89424V micrel input s1 s2 s3 fout, fout frequency range mhz f osc (1) 0 0 0 24x f osc 240 480 0 0 1 12x f osc 120 240 0 1 0 8x f osc 80 160 0 1 1 6x f osc 60 120 1 0 0 50x f osc 500 1000 1 0 1 25x f osc 250 500 1 1 0 16.67x f osc 167 333 1 1 1 12.5x f osc 125 250 pin names pin function i/o xtal 1 crystal input 1 (pecl) i/o xtal 2 crystal input 2 (pecl) i/o f1 filter pin 1 f2 filter pin 2 (reference) v ccq positive power supply (charge pump) s1 select input 1 (ttl) i s2 select input 2 (ttl) i s3 select input 3 (ttl) i fout output (pecl) o fout complement output (pecl) o v cc positive power supply (logic) v cco positive power supply (pecl outputs) oe output enable (ttl) i v ee negative power suppy (0.0v) pdr 1 pulldown resistor (100 ? ) pdr 2 pulldown resistor (100 ? ) pin configuration frequency selection table note: 1. f osc = 10mhz to 25mhz. absolute maximum rating (1) symbol parameter value unit v cc power supply voltage 0.5 to +7.0 v v i ttl input voltage (2) 0.5 to 6.0 v i i ttl input current (2) 30 to +5.0 ma i out ecl output current continuous 50 ma surge 100 t store storage temperature 65 to +150 c t a operating temperature 0 to +75 c notes: 1. permanent device damage may occur if absolute maximum ratings are exceeded. this is a stress rating only and functional oper ation is not implied at conditions other than those detailed in the operational sections of this data sheet. exposure to absolute maximum r ating conditions for extended periods may affect device reliability. 2. either voltage limit or current limit is sufficient to protect input. v ee f1 pdr 1 top view gullwing 116 2 15 3 14 413 512 6 11 7 10 89 oe xtal 1 xtal 2 s1 v ccq v cc s3 f2 fout fout pdr 2 v cco s2
3 clockworks SY89424V micrel symbol parameter min. typ. max. unit condition v o output voltage swing 0.55 0.85 1.15 v peak-to-peak v oh output high voltage v cc 1.075 v cc 0.800 v fout & fout loaded with 50 ? to v cc 2.0v v ol output low voltage v cc 1.860 v cc 1.570 v fout & fout loaded with 50 ? to v cc 2.0v v ih input high voltage (1) v cc 1.165 v cc 0.880 v v il input low voltage (1) v cc 1.810 v cc 1.475 v symbol parameter min. typ. max. unit condition v cc power supply voltage 4.75 5.25 v v cc = v ccq = v cco i cc power supply current (v cc ) 80 ma i ccq power supply current (v ccq ) 10 ma i cco power supply current (v cco ) 20 ma pecl outputs fout & fout are open symbol parameter min. typ. max. unit condition v ih input high voltage 2.0 v v il input low voltage 0.8 v i ih input high current 20 av in = 2.7v 100 v in = v cc i il input low current 0.2 ma v in = 0.5v v ik input clamp voltage 1.2 v i in = 18ma 5v dc electrical characteristics pecl dc electrical characteristics ttl dc electrical characteristics v cc = v ccq = v cco = 3.0v to 5.25v v cc = v ccq = v cco = 4.75v to 5.25v v cc = v ccq = v cco = 3.0v to 5.25v note: 1. forcing voltage at xtal 1 and xtal 2 symbol parameter min. typ. max. unit condition v cc power supply voltage 3.0 3.8 v v cc = v ccq = v cco i cc power supply current (v cc ) 68 ma i ccq power supply current (v ccq ) 9ma i cco power supply current (v cco ) 18 ma pecl outputs fout & fout are open 3.3v dc electrical characteristics v cc = v ccq = v cco = 3.0v to 5.25v
4 clockworks SY89424V micrel odering package operating code type range SY89424Vzc z16-1 commercial SY89424Vzctr z16-1 commercial ac coupled load c b2 = 10nf 20% r s = 6.8 ohm 5% r c = 20 ohm 1% r r = 5 kohm 5% z o = 20 ohm 2 ohm application + v ee on chip pulldown resistor provides 25ma (40ma at 5v v cc ) of driver current. v term = 2.5v z o clock interface r s c b2 r r to clock inputs v ee = gnd r c product ordering code symbol parameter min. typ. max. unit condition t jit jitter 10 ps rms p pw duty cycle 45% 50% 55% <500mhz t r output rise/fall time 100 300 500 ps t f (20% to 80%) 100 300 500 ac electrical characteristics v cc = v ccq = v cco = 3.0v to 5.25v
5 clockworks SY89424V micrel 16 lead soic .300" wide (z16-1) rev. 03 micrel-synergy 3250 scott boulevard santa clara ca 95054 usa tel + 1 (408) 980-9191 fax + 1 (408) 914-7878 web http://www.micrel.com this information is believed to be accurate and reliable, however no responsibility is assumed by micrel for its use nor for an y infringement of patents or other rights of third parties resulting from its use. no license is granted by implication or otherwise under any patent or pat ent right of micrel inc. ? 2000 micrel incorporated
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