1 multimedia ics video signal switcher BA7644AN the BA7644AN is a four-channel analog multiplexer with mute, designed for use in video cassette recorders. it fea- tures a wide dynamic range, and wide operating frequency range, and is suitable for switching audio and video sig- nals. applications vcr, tv and audio signal switching features 1) 4-input / 1-output switches. 2) built-in mute. 3) wide operating supply voltage range (4.5v to 13.0v). 4) low power consumption (48mw typ.). 5) excellent frequency characteristics (10mhz, 0db typ.). 6) wide dynamic range (3.5v p-p typ.). 7) high input impedance (20k w typ.). 8) low interchannel crosstalk ( ?65db typ., f = 4.43mhz). absolute maximum ratings (ta = 25?) parameter symbol unit v cc 13.5 v 850 * mw c c limits pd topr tstg ?25 ~ + 75 ?55 ~ + 125 power supply voltage power dissipation operating temperature storage temperature * reduced by 8.5mw for each increase in ta of 1 c over 25 c. block diagram 1 in1 2 ctla 3 ctlb 4 logic mute in2 5 ctlc 6 in3 7 v cc 8 in4 9 gnd 10 v out truth table out l (open) l (open) l (open) in1 l (open) h l (open) in2 h l (open) l (open) in3 h h l (open) in4 * * hmute ctl - a ctl - b ctl - c * either "l (open)" or "h".
2 multimedia ics BA7644AN equivalent circuits 100 m a 100 m a vcc in d2 q1 q2 r2 r1 100 d1 20k clamp input 2ma vcc q1 d1 out d2 output output impedance 20 w [typ.] * output dc voltage 2.2v (v cc = 5v, typ.) * * reference value 100 50k 20k 34k vcc ctla / b r4 r1 d2 r2 r3 q3 ctla / ctlb 100 45k 30k 29k vcc ctlc r4 r1 d2 r2 r3 q3 ctlc input bias current 1 m a (typ.) * input bias voltage 3.68v (v cc = 5v, typ.) *
3 multimedia ics BA7644AN electrical characteristics (unless otherwise noted, ta = 25? and v cc = 5v) parameter symbol min. typ. max. unit conditions v cc 4.5 13.0 v i cc 9.5 14.5 ma 3.0 3.5 g v ?0.5 0 c tin ?65 ?55 db c f ?3.0 0 thd 0.007 % z in 14 20 26 k w 1.0 2.0 3.0 v 1.0 2.0 3.0 v 1.0 2.0 3.0 v v om db db db v th-a v th-b v th-c v p-p in - in in - mute f = 1khz, thd = 0.5% f = 1mhz, v in = 1.0v p-p f = 4.43mhz, v in = 1.0v p-p f = 4.43mhz, v in = 1.0v p-p f = 1khz, v in = 1.0v p-p f = 10mhz / 1mhz, v in = 1.0v p-p c tm 1.0 0.5 operating voltage supply current maximum output level voltage gain interchannel crosstalk frequency characteristic total-harmonic distortion input impedance ctl pin switching level a ctl pin switching level b ctl pin switching level c s not designed for radiation resistance. measurement circuit logic mute v sw 1 50 w osc 1 m f 1 m f 50 m a 1 23 sw 2 50 w osc 1 m f 1 m f 50 m a 1 23 sw 4 50 w osc 1 m f 1 m f 50 m a 1 23 sw 3 50 w osc 1 m f 1 m f 47 m f 0.022 m f 50 m a 1 23 sw 5 v cc v cc v cc v cc p - p sw 6 sw 7 12 3 12 3 12 3 v v v a 1 2 3 4 5 6 7 8 9 10 fig. 1 + v ~ ~ ~ ~
4 multimedia ics BA7644AN measurement conditions sw 1 sw 2 sw 3 sw 4 sw 5 sw 6 sw 7 i cc 2222222 in 1 in 2 in 3 in 4 v om v om v om 1 2 2 2 2 1 2 2 2 2 1 2 2 2 2 1 3 3 2 2 3 2 3 2 3 3 3 3 in1 in2 in3 in4 g v g v g v g v 1 2 2 2 2 1 2 2 2 2 1 2 2 2 2 1 3 3 2 2 3 2 3 2 3 3 3 3 in1 ? in3 in1 ? in4 in1 ? mute in2 ? in3 in2 ? in4 in2 ? mute in3 ? in4 in3 ? mute in4 ? mute in1 ? in2 c t c t c t c t c t c t c t c t c t c t 1 1 1 1 2 2 2 2 2 2 2 2 2 2 1 1 1 2 2 2 2 2 2 2 2 2 2 1 1 2 2 2 2 2 2 2 2 2 2 1 3 2 2 * 2 2 * 2 * * 2 3 2 * 3 2 * 2 * * 3 3 3 2 3 3 2 3 2 2 in 1 in 2 in 3 in 4 g f g f g f g f 1 2 2 2 2 1 2 2 2 2 1 2 2 2 2 1 3 3 2 2 3 2 3 2 3 3 3 3 v in = 1v p-p in 1 in 2 in 3 in 4 thd thd thd thd 1 2 2 2 2 1 2 2 2 2 1 2 2 2 2 1 3 3 2 2 3 2 3 2 3 3 3 3 f = 1khz in 1 in 2 in 3 in 4 z in z in z in z in 3 2 2 2 2 3 2 2 2 2 3 2 2 2 2 3 3 3 2 2 3 2 3 2 3 3 3 3 v th v th v th 2 2 1 2 1 2 1 2 2 2 2 2 1 3 3 3 1 3 3 3 1 v in = 1v p-p ctl - a ctl - b ctl - c f = 1khz, thd = 0.5% f = 1mhz, v in = 1v p-p f = 4.43mhz, f = 10mhz / f = 1mhz v in = 1v p-p v om * anywhere is possible. note 1: connect a distortion meter to the output, and input a f = 1khz sine wave. adjust the input level until the output disto rtion is 0.5%. this output voltage at this time is the maximum output level v om (v p-p ). note 2: input a 1v p-p , 1mhz sine wave. the voltage gain is given by g v = 20 log (v out / v in ). note 3: input a 1v p-p , 4.43mhz sine wave. the interchannel crosstalk is given by c t = 20 log (v out / v in ). note 4: input 1v p-p , 1mhz and 10mhz sine waves. the frequency characteristic is given by g f = 20 log (v out (f = 10mhz) / v out (f = 1mhz)). note 5: input a 1v p-p , 1mhz sine wave and measure the total-harmonic distortion of the output using a total-harmonic distortion meter. note 6: measure the input pin voltage v in 50 when a current of dc50 m a is flowing into the input pin. measure the input pin open-circuit voltage. the input impedance is given by z = (v in50 - v in0 ) / 50 10 -6 [ w ]. note 7: input a 1v p-p , 1mhz sine wave. reduce the ctl pin voltage from v cc . the ctl pin switching level (v th ) is the ctl pin voltage at which the v out level drops below 20mv p-p . note 8: input a 1v p-p , 1mhz sine wave. increase the ctl pin voltage from 0v. the ctl pin switching level (v th ) is the ctl pin voltage at which the v out level goes above 1.0v p-p . parameter symbol switch settings measurement method current dissipation ammeter maximum output level note 1 voltage gain note 2 interchannel crosstalk note 3 frequency characteristic note 4 total-harmonic distortion note 5 input impedance note 6 ctl pin switching level note 7 note 8
5 multimedia ics BA7644AN electrical characteristic curves output voltage: v out (v p-p ) input voltage: v in (v p-p ) 10 9 8 7 6 5 4 3 2 1 0 012345678 9 10 v cc = 12v v cc = 9v v cc = 5v fig. 2 v in vs. v out (f = 1khz) external dimensions (units: mm) sip10 2.8 0.2 25.2 0.2 10.5 0.5 0.6 1.3 10 2.54 3.5 0.5 1 5.8 0.2 1.2 0.3 0.1 0.8 voltage gain: c f (db) frequency: f (hz) ?4 100k 300k 1m 3m 10m 30m 100m ?2 2 0 4 fig. 3 frequency characteristics crosstalk: c t (db) frequency: f (hz) ?80 100k 300k 1m 3m 10m 30m 100m ?60 ?40 ?20 0 20 fig. 4 interchannel crosstalk
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