integrated circuit systems, inc. general description features av 9173 -15 block diagram video genlock pll av9173-15revc051397p ? phase-detector/vco circuit block ? ideal for genlock system ? reference clock range 12 khz to 1 mhz (see specification of output clock range) ? output clock range 0.625 to 37.5 mhz for clk1, depending on input conditions (see table 1) on page 2. ? provides h-sync capability with clk1 outputs 15 to 37.5 mhz for 15khz input ? on-chip loop filter ? single 5 volt power supply ? low power cmos technology ? small 8-pin dip or soic package the av9173-15 provides the analog circuit blocks required for implementing a video genlock dot (pixel) clock generator. it contains a phase detector, charge pump, loop filter, and voltage-controlled oscillator (vco). by grouping these critical analog blocks into one ic and utilizing external digital functions, performance and design flexibility are optimized as are development time and system cost. when used with an external clock divider, the av9173-15 forms a phase-locked loop configured as a frequency synthesizer. the av9173-15 is designed to accept video horizontal synchronization (h-sync) pulses and produce a video dot clock. a separated, negative-going sync input reference pulse is required at pin 2 (i n). the av9173-15 is also suited for other clock recovery applications in such areas as data communications. ics reserves the right to make changes in the device data identified in this publication without further notice. ics advises its customers to obtain the latest version of all device data to verify that any information being relied upon by the customer is current and accurate.
2 av9173-15 pin descriptions pin configuration 8-pin dip or soic table 1: allowable input frequency to output frequency (outputs in mhz) pin number pin name type description 1 fbin input feedback input 2 in input input for reference sync pulse 3 gnd ground 4 fs0 input internal vco divider select input 5 oe input output enable 6 clk1 output clock output 1 7 vdd power supply (+5v) 8 clk2 output clock output 2 (divided-by-2 from clock 1) f in (khz) f out for fs = 0 (mhz) f out for fs = 1 (mhz) clk1 output clk2 output clk1 output clk2 output 12 f in 14 khz 22.0 to 37.5 11.0 to 18.75 5.5 to 9.375 2.75 to 4.6875 14 < f in 17 khz 15 to 37.5 7.5 to 18.75 3.75 to 9.375 1.875 to 4.6875 17 < f in 30 khz 12.5 to 37.5 6.25 to 18.75 3.125 to 9.375 1.5625 to 4.6875 30 < f in 35 khz 7.5 to 37.5 3.75 to 18.75 1.875 to 9.375 0.9375 to 4.6875 35 < f in 1000 khz 5.0 to 37.5 2.5 to 18.75 1.25 to 9.375 0.625 to 4.6875
3 av9173 -15 using the av9173-15 figure 1: typical application of av9173-15 in a video genlock system most video sources, such as video cameras, are asynchronous, free-running devices. to digitize video or synchronize one video source to another free-running reference video source, a video genlock (generator lock) circuit is required. the av9173-15 integrates the analog blocks which make the task much easier. in the complete video genlock circuit, the primary function of the av9173-15 is to provide the analog circuitry required to generate the video dot clock within a pll. this application is illustrated in figure 1. the input reference signal for this circuit is the horizontal synchronization (h-sync) signal. if a composite video reference source is being used, the h-sync pulses must be separated from the composite signal. a video sync separator circuit, such as the national semiconductor lm1881, can be used for this purpose. the clock feedback divider shown in figure 1 is a digital divider used within the pll to multiply the reference frequency. its divide ratio establishes how many video dot clock cycles occur per h-sync pulse. for example, if 880 pixel clocks are desired per h-sync pulse, then the divider ratio is set to 880. hence, together the h-sync frequency and external divider ratio establish the dot clock frequency: f out = f in ? n where n is external divide ratio both av9173-15 input pins in and fbin respond only to negative-going clock edges of the input signal. the h-sync signal must be constant frequency in the 12 khz to 1 mhz range and stable (low clock jitter) for creation of a stable output clock. the output hook-up of the av9173-15 is dictated by the desired dot clock frequency. the primary consideration is the internal vco which operates over a frequency range of 10 mhz to 75 mhz. because of the selectable vco output divider and the additional divider on output clk2, four distinct output frequency ranges can be achieved. the following table lists these ranges and the corresponding device configuration. note that both outputs, clk1 and clk2, are available during operation even though only one is fed back via the external clock divider. pin 5, oe, tristates both clk1 and clk2 upon logic low input. this feature can be used to revert dot clock control to the system clock when not in genlock mode (hence, when in genlock mode the system dot clock must be tristated). when unused, inputs fs0 and oe must be tied to either gnd (logic low) or vdd (logic high). for further discussion of vco/pll operation as it applies to the av9173-15 , please refer to the av9170 application note. the av9170 is a similar device with fixed feedback dividers for skew control applications. fs0 state output used frequency range 0 0 1 1 clk1 clk2 clk1 clk2 5 - 37.5 mhz 2.5 - 18.75 mhz 1.25 - 9.375 mhz 0.625 - 4.6875 mhz
4 av9173-15 absolute maximum ratings v dd (referenced to gnd) . . . . . . . . . . . . . . . . 7.0 v operating temperature under bias . . . . . . . . . 0 c to + 70 c storage temperature . . . . . . . . . . . . . . . . . . . . C 65c to + 150c voltage on i/o pins referenced to gnd . . . . . gnd C 0.5 v to v dd + 0.5 v power dissipation . . . . . . . . . . . . . . . . . . . . . . 0.5 watts stresses above those listed under absolute maximum ratings above may cause permanent damage to the device. this is a stress rating only and functional operation of the device at these or any other conditions above those listed in the operational sections of the specifications is not implied. exposure to absolute maximum rating conditions for extended periods may affect product reliability. v dd = + 5v 5%, t a = 0c to 70c, unless otherwise stated electrical characteristic notes: 1. parameter is guaranteed by design and characterization. not 100% tested in production. dc characteristics parameter symbol test conditions min typ max units input low voltage v il v dd = 5v 0.8v input high voltage v ih v dd = 5v 2.0 v input low current i il v in = 0v - 5a input high current i ih v in = v dd - 55 a output low voltage 1 v ol i ol = 8ma 0.4 v output high voltage 1 v oh1 i oh = -1ma, v dd = 5.0v v dd -.4v v output high voltage 1 v oh2 i oh = -4ma, v dd = 5.0v v dd -.8v v output high voltage 1 v oh3 i oh = -8ma 2.4 v supply current i dd unloaded, 50 mhz 20 50 ma
5 av9173 -15 v dd = + 5v 5%, t a = 0c to 70c, unless otherwise stated electrical characteristics notes: 1. parameter is guaranteed by design and characterization. not 100% tested in production. 2. input reference frequency = 25 khz, output frequency = 25 mhz. jitter measured between adjacent vertical pixels. 3. clk1 frequency applies for fs = 0. for fs = 1 condition, divide allowable clk1 range by the factor of 4. ac characteristics parameter symbol test conditions min typ max units input clock rise time 1 iclk r 10 ns input clock fall time 1 iclk f 10 ns output rise time 1 t r1 15pf load; 0.8 to 2.0v 0.6 1.5 ns rise time 1 t r2 15pf load; 20% to 80% v dd 1.3 3.0 ns output fall time 1 t f1 15pf load; 2.0 to 0.8v 0.6 1.5 ns fall time 1 t f2 15pf load; 80% to 20% v dd 0.7 2.0 ns output duty cycle 1 d t 15pf load, v t h =1.4v 40 47 55 % jitter, 1 1 sigma t 1s1 clk1 freq. 3 12.5 mhz 120 250 ps jitter, 1 1 sigma t 1s2 clk1 freq. 3 12.5 mhz 1 % jitter, 1 1 absolute t abs1 clk1 freq. < 12.5 mhz -400 250 400 ps jitter, 1 1 absolute t abs2 clk1 freq. < 12.5 mhz 2 % line-to-line jitter, 1 absolute 2 tl abs 4ns input frequency, 1 in or fbin f i1 f vco 10 to 75 mhz 12.0 1000 khz clk1 frequency 3 f clk1 12 f i 14 khz 22.0 37.5 mhz 14 < f i 17 khz 15.0 37.5 mhz 17 < f i 30 khz 12.5 37.5 mhz 30 < f i 35 khz 7.5 37.5 mhz 35 < f i 1000 khz 5.0 37.5 mhz
6 av9173-15 ordering information av9173-15cn08 - or - av9173-15cs08 8-pin dip package 8-pin soic package xxx xxxx - ppp m x#w lead count & package width lead count = 1, 2 or 3 digits w = 0.3" soic or 0.6" dip; none = standard width package type n = dip (plastic) s = soic pattern number (2 or 3 digit number for parts with rom code patterns) device type (consists of 3 or 4 digit numbers) prefix ics, av = standard device example: product preview documents contain information on products in the formative or design phase development. charactersitic data and other specifications are design goals. ics reserves the right to change or discontinue these procucts without notice.
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