1 video ics stereo zoom microphone amplifier for camcorders BA7780KV the BA7780KV is a microphone amplifier developed for use in camcorders. the ic features an electronic volume cir- cuit for presetting the curve required for the stereo zoom function, a microphone element power supply regulator, a wind-noise rejection filter, a current limiting circuit for external accessory power supplies, and an input for external microphone input. the ic operates off a 3.3v power supply. applications camcorders features 1) operates off a 3.0v to 5.25v power supply. 2) zoom microphone processing function on one chip. 3) built-in electronic volume for external setting of sen- sitivity and control voltage. 4) adjustable microphone element sensitivity. 5) matrix amplifier for stereo emphasis. 6) automatic switching circuit for external inputs, and built-in external monaural decision circuit. absolute maximum ratings (ta = 25?) recommended operating conditions (ta = 25?) parameter symbol limits unit v cc 7.0 v pd 750 * mw topr c tstg c ?10 ~ + 70 ?55 ~ + 125 power supply voltage power dissipation operating temperature storage temperature * reduced by 7.5mw for each increase in ta of 1 c over 25 c. parameter symbol min. typ. max. unit v ccs 3.0 5.25 v power supply voltage
2 video ics BA7780KV block diagram 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 mix rec ext int 13db gc + 15db 5db ext int balance rflt ext int 13db rflt mix 13db balance int: 0n gc 15db 5db ext int bias hpfc cimt 13db out l mic mono z b z a z sense z point gain cont ex v cc out ex v cc v cc z ac z bc in moni hpf cont bias sub out r bg sub in l int in l vreg l ext in l mode 43 pre out l out amp in l inv out l gc out l mtx in l mtx out l bl out l hpf in l bias l extc l ripl sub in r int in r vreg r ext in r mode 6 pre out r out amp in r inv out r gc out r mtx in r mtx out r bl out r hpf in r bias r extc r gnd l mix1 in l gz cont sub inv2 out sub inv2 in sub buf2 out sub vca out sub vca in mix2 out sub buf2 in sub inv1 out sub buf1 out sub buf1 in mix1 out mix1 in r gnd r int: on reg + +
3 video ics BA7780KV pin descriptions 1 ripl 1.65 50k w 2 1.65 100k w 3 1.65 75k w 4 2.5 c 5 1.65 75k w 6 25k w 7 1.65 ef (p - p) 8 1.65 100k w 9 1.65 ef (p - p) 10 1.65 ef (p - p) 11 1.65 b 12 1.65 ef (p - p) 13 1.65 ef (p - p) 14 1.65 100k w 15 1.65 ef (p - p) 16 2.3 c 17 1.65 c (p - p) 18 1.65 ef (p - p) 19 10k w 20 ? 21 ? 22 ? 23 v cc 3.3 24 4.75 25 4.5 c 26 50k w 27 ? 28 ? 29 ? 30 ? 31 ? 32 1.65 ef (p - p) 33 2.3 c 34 1.65 ef (p - p) 35 1.65 100k w 36 1.65 ef (p - p) 37 1.65 ef (p - p) 38 1.65 b 39 1.65 ef (p - p) 40 1.65 ef (p - p) 41 1.65 100k w 42 1.65 ef (p - p) sub in r int in r vreg r ext in r mode 6 out amp in r pre out r inv out r gc out r mtx in r mtx out r bl out r hpf in r bias r extc r out r bias sub hpf cont in moni z bc z ac ex v cc ex v cc out gain cont z point z sense z a z b mic mono out l extc l bias l hpf in l bl out l mtx out l mtx in l gc out l inv out l out amp in l pre out l pin no. for bias ripple filter capacitor sub microphone input internal microphone input regulator output external microphone input mode control 6 input preamplifier output out amplifier input inverter output gain control amplifier output matrix amplifier input matrix amplifier output zoom balance circuit output hpf input bias output for connection of out amplifier output inhibit capacitor signal output sub bias output hfp control input input switch decision signal output for connection of noise cutting capacitor for zoom control signal for connection of noise cutting capacitor for zoom control signal v cc current limiter v cc current limiter output gain control amplifier switch input cross-point variation input for zoom balance circuit sensitivity variation input for zoom balance circuit zoom control input zoom control input external microphone monaural decision signal output signal output for connection of out amplifier output inhibit capacitor bias output hpf input zoom balance circuit output matrix amplifier output matrix amplifier input gain control amplifier output inverter output out amplifier input preamplifier output pin voltage ( v) format function pin name
4 video ics BA7780KV pin no. 43 mode 43 25k w 44 ext in l 1.65 75k w 45 vreg l 2.5 c 46 int in l 1.65 75k w 47 sub in l 1.65 100k w 48 bg 1.25 10k w 49 gnd l 50 mix 1 in l 1.65 100k w 51 gz cont 50k w 52 sub inv2 out 1.65 ef (p - p) 53 sub inv2 in 1.65 b 54 sub buf2 out 1.65 ef (p - p) 55 sub vca out 1.65 ef (p - p) 56 sub vca in 1.65 100k w 57 mix2 out 1.65 ef (p - p) 58 sub buf2 in 1.65 100k w 59 sub inv1 out 1.65 ef (p - p) 60 sub buf1 out 1.65 ef (p - p) 61 sub buf1 in 1.65 100k w 62 mix1 out 1.65 ef (p - p) 63 mix1 in r 1.65 100k w 64 gnd r pin voltage (v) format function pin name mode control 43 input external microphone input regulator output internal microphone input sub microphone input for regulator ripple filter capacitor left channel gnd mixer amplifier input sub vca control input sub inverter 2 output sub inverter 2 input sub buffer 2 output sub vca output sub vca input mixer 2 output sub buffer 2 input sub inverter 1 output sub buffer 1 output sub buffer 1 input mixer 1 output mixer 1 input right channel gnd * ef: emitter follower, p-p: push pull, b: base, and c: collector. all numerical values are standardized values.
5 video ics BA7780KV parameter symbol min. typ. max. unit conditions i qe 8.5 12.0 ma gv e 27.0 28.0 29.0 db gv ih 21.5 24.5 27.5 db gv im 18.5 21.5 24.5 db gv il 16.5 18.5 21.5 db thd w 0.05 0.5 % thd e 0.1 0.25 % thd z 0.15 0.5 % v om 0.75 0.95 v rms v one ?060 m v rms v onw ?060 m v rms v onz 60 120 m v rms ct ie 76 ?70 db ct ch 76 ?70 db gv glr ?1.5 0.0 1.5 db 10 39 gv ilr ?1.5 0.0 1.5 db 940 v reg 2.3 2.5 2.75 v v ext 4.3 4.5 v i ltd 30 ma v hswh 1.6 v v hswl 0 0.7v v hgh 2.8 v v hgm 1.3 2.0 v v hgl 0 0.5v v hhpfh 2.0 v v hhpfl 0 0.5v gv m1-1 ?7.0 6.0 5.0 db gv m1-2 ?1.0 0 1.0 db gv m2-1 6.0 7.0 8.0 db gv m2-2 ?1.0 0 1.0 db ext mic in, v o = 300mv rms note 1 note 2 v cc v cc v cc gain ctl h int mic in, zoom, v o = 300mv rms int mic in, wide, vo = 300mv rms int mic in, gain ctl l int mic in, gain ctl m int mic in, gain ctl h ext mic in int / ext mic in, no input pins 29 and 30 = 0v, gain ctl h int mic in, hml, int mic in, hml, hpf off, 19pin dc hpf on, 19pin dc 63 ? 62 / 50 ? 62 pin int l / m / h, 2 ? 57, 47 ? 57pin int / ext mic in, thd = 1% * 2 ext mic in, r g = 1k w * 1 int mic in, r g = 1k w * 1 int mic in, r g = 1k w * 1 current dissipation voltage gain 1 voltage gain 2 voltage gain 3 voltage gain 4 distortion 1 distortion 2 distortion 3 maximum output output noise voltage 1 (ext) output noise voltage 2 (int, wide) output noise voltage 3 (int, zoom) input switch crosstalk (int to ext) interchannel crosstalk gc out l / r gain differential inverter out l / r gain differential internal microphone power supply output voltage external power supply output voltage external power supply limit current input switching ctl holding voltage gain switching ctl holding voltage hpf, ctl holding voltage mix 1 gain mix 2 gain pins 4 and 45 output current for 30k w load pin 25 dc for pin 25 output current of 25ma pin 25 output current when grounded ??level, pin 6 / 43 dc ??level, pin 6 / 43 dc ??level, pin 26 dc ??level, pin 26 dc ??level, pin 26 dc gain differential for pins 63 to 62 and 50 to 62 gain differential for pins 2 to 57 and 47 to 57 electrical characteristics measurement conditions unless otherwise noted, the following conditions apply: ta = 25?, v cc 3.3v, external supply voltage (pin 24) = 4.75v, pin 19 = ??or open, pin 26 = 1 / 2v cc , pin 51 = 0.58 pin 4, pin 27 = 0.733 pin 4, pin 28 = 0.80 pin 4, pin 29 = 2.2v, pin 30 = 2.2v input signal level int = ?31.5dbv ext = ?38.5dbv sub = ?33.5dbv (1khz) monitoring pins: 17 and 32 * 1 jis? filter used * 2 400hz to 30khz filter used
6 video ics BA7780KV gv z1-1 ?23.0 20.0 17.0 db 29, 30 pin 0.0v (dc) gv z1-2 ?11.7 7.7 4.7 db 29, 30 pin 0.8v (dc) gv z1-3 ?2.0 1.0 4.0 db 29, 30 pin 2.2v (dc) gv z2-1 ?23.0 20.0 17.0 db 29, 30 pin 2.2v (dc) gv z2-2 ?11.7 7.7 4.7 db 29, 30 pin 1.4v (dc) gv z2-3 ?2.0 1.0 4.0 db 29, 30 pin 0.0v (dc) parameter symbol unit conditions min. typ. max. gv z3? ?2.5 0.5 3.5 db 27 pin 0.64 4pin (dc) gv z3? ?7.5 4.5 1.5 db 27 pin 0.733 4pin (dc) gv z3? ?20.6 17.0 12.0 db 27 pin 0.82 4pin (dc) gv z4? ?5.5 2.5 0.5 db 28 pin 0.59 4pin (dc) gv z4? ?9.5 6.5 3.5 db 28 pin 0.69 4pin (dc) gv z4? ?17.5 14.5 11.5 db 28 pin 0.8 4pin (dc) gv vca1 ?5.0 3.0 1.0 db 51 pin 0.74 4pin (dc) gv vca2 ?2.0 0.0 2.0 db 51 pin 0.58 4pin (dc) gv vca3 1.0 3.0 5.0 db 51 pin 0.48 4pin (dc) 12 ? 13 or 37 ? 36 pin 52 ? 13 or 52 ? 36 pin 28 pin 0.8 4pin, 29 30 pin 1.1v, 12 ? 13 or 37 ? 36 pin 27 pin 0.733 4pin, 29 30 pin 0.4v, 12 ? 13 or 37 ? 36 pin sub vca gain variable slope variable position gain 2 gain 1 rch / lch rch / lch rch / lch rch / lch 56pin 55pin zoom - balance zoom - balance zoom - balance zoom - balance note 1: input switch crosstalk measurement method: (pin 19 = ??or open, pin 26 = gnd, pin 27 = 0.733 pin 4, pin 28 = 0.80 pin 4, pin 29 = 2.2v, pin 30 = 2.2v) input 1khz signals on the int input pins (3 and 46) in int input mode that give a distortion of 1% at the signal output pins (1 7 and 32), then connect the ext input pins (5 and 44) to gnd via r g = 1k w switch to ext input mode, and measure the relative output level of the output pins (17 and 32). note 2: interchannel crosstalk measurement method: the mode pin conditions are the same as for input switch crosstalk. connect the input pin of the channel to be measured to gnd via r g = 1k w . input a 1khz signal on the other channel's input that gives a distortion of 1% on the signal output pins (17 and 32), and measure the relative output level between the signal output pins (17 and 32).
7 video ics BA7780KV 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 mix ext int 13db gc 15db 5db ext int balance ext int 13db mix 13db balance gc 15db 5db ext int bias cimt 13db mic mono z b z a v cc z ac z bc in moni sub bias 10k 10k 0.1 0.1 0.1 0.1 30k 0.1 0.1 2200p 0.022 1 2 10 + 0.1 0.1 10k 10k 10k 32k 1 2 3 sw1 0.1 0.1 0.1 0.1 470p sw3 10k 10k 0.1 0.1 0.1 0.1 30k 0.1 0.1 2200p 0.022 1 2 10 + 470p mode6 sw2 mode43 gnd z sense z point gain cont ex v cc out ex v cc in int: on int: on sub mic in int mic in ext mic in ext mic in int mic in sub mic in rflt rflt gz cont reg reg lch out rch out hpf on / off units: hpfc r [ w ] c [ m f ] fig. 1 ? ? + measurement circuit
8 video ics BA7780KV sw1 sw2 sw3 mode6 mode43 gain ctl 1 1 1 h, l h, l m ll m ext h h int m int l int 2hlm int 2 l l ext 1 h l m sub 1 h, l l l int, ext, sub 2ll 2hlh 3hlh 2 l l l int int 2 h l m int ext 2 l l ext 1 h l h, m, l int 1 h l h, m, l int 2 h vth int, ext 2 vth l int, ext 2 h l vth int 2 h l vth int 2 h l vth int 2 2.1 2.1 h l h l m int h l sub 2 h l m int 1 h l m sub 2 h l m int 2 h l m int h l sub int, vth of pin 19 signal input pin parameter current dissipation voltage gain 1 voltage gain 2 voltage gain 3 voltage gain 4 distortion 1 distortion 2 distortion 3 maximum output output noise voltage 1 (ext) output noise voltage 2 (wide) output noise voltage 3 (zoom) input switch crosstalk (int to ext) interchannel crosstalk gc out l / r gain differential inverter out l / r gain differential internal microphone power supply voltage external power supply output voltage external power supply limit current input switching ctl holding voltage gain switching ctl holding voltage hpf, ctl holding voltage mix 1 gain mix 2 gain zoom - balance gain 1 zoom - balance gain 2 zoom - balance variable position zoom - balance variable inclination sub vca gain * gain ctl pin 26. h, m, and l are v cc , 1/2v cc , and gnd respectively. measure the voltage range that maintains the mode for vth. measurement circuit switching table (blank cells: no spesification)
9 video ics BA7780KV 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 mix ext int 13db gc 15db 5db ext int balance rflt ext int 13db rflt mix 13db balance int: 0n gc 15db 5db ext int bias cimt int: 0n 13db mic mono z b z a v cc z ac z bc in moni sub bias 10k 0.1 0.1 0.1 0.1 0.1 0.022 10 + 0.1 0.1 10k 10k 10k 0.1 0.1 0.1 470p 0.1 0.1 0.1 0.1 10 + 0.022 2200 6800 2200 0.022 2200 6800 2200 33k 3300 12k 6800p 6800p 0.047 3300 10k 2200p 22k 0.022 0.022 8200 10k 0.1 0.022 470p 33k 3300 12k 6800p 6800p 0.047 3300 10k 2200p 22k 0.022 0.022 8200 5600p 10k gnd 10k 0.010 0.01 1k 1500 10k 2700p 10k ext mic in int mic in sub mic in sub mic in int mic in ext mic in 6800p 3900p 47k z sense z point gain cont ex v cc out ex v cc in g z cont hpf on / off reg lch out rch out hpfc reg units: r [ w ] c [ m f ] fig. 2 ? ? + application example
operation notes points to note regarding zoom operation when using a microprocessor to vary the voltages on pins 29 and 30 after presetting the electronic volume sensitivity and control volt- age range, and with the pin 27 and 28 voltage fixed at a certain level, it is possible to minimize drift in the zoom characteristics due to tempreature fluctuations and differences between individual ics by setting the pin 27 and 28 voltages using resistive voltage divider circuits connected to the pin 4 regulator voltage output. 10 video ics BA7780KV electrical characteristic curves 17, 32pin output attenuation level: gv z1 (db) 29, 30pin control voltage: v ctl (v) ?20 0.1 ?15 ?10 ?5 0 0.6 1.1 1.6 2.1 28pin = 1.64v 1.84v 1.94v 2.04v 28pin = 1.64v 1.84v 1.94v 2.04v ta = 25 c 12 ? 13, 37 ? 36pin 52 ? 13, 52 ? 36pin 0 2.2 fig. 4 zoom control slope variation characteristics 4 27 28 fig. 3 17, 32pin output attenuation level: gv z1 (db) 29, 30pin control voltage: v ctl ( v ) ?20 0.1 ?15 ?10 ?5 0 0.6 1.1 1.6 2.1 27pin = 1.67v 1.87v 1.67v ta = 25 c 12 ? 13, 37 ? 36pin 52 ? 13, 52 ? 36pin 2.07v 1.87v 27pin = 1.67v 0 2.2 fig. 5 zoom control position variation characteristics external dimensions (units: mm) vqfp64 48 33 32 17 16 1 49 64 10.0 0.2 12.0 0.3 10.0 0.2 12.0 0.3 0.2 0.1 0.5 0.125 0.1 0.5 0.10 1.4 0.1 0.10
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