bh7272kv ROHM Co. Ltd., bh7272kv Datasheet
bh7272kv
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bh7272kv Summary of contents
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... Digital VCRs BH7272KV The BH7272KV is a head amplifier developed for use in digital video cassette recorders. Both PB and REC have excellent frequency characteristics making this IC an ideal choice for digital recording and playback. The small VQFP48 package facilitates compact design of portable equipment such as video cameras. ...
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... REC current amplifier As above Bias, REC limiter amplifier Bias, control logic REC limiter amplifier PB amplifier, PB AGC, peak amplifier As above PB first-stage amplifier PB first-stage amplifier, REC current amplifier Control logic BH7272KV LIMIT LEVEL adj 24 LIMIT 23 LIMIT Vth adj 22 REC LIMIT – OUT ...
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... Pins 2, 11 output level differential V Pins 46 voltage to hold PB V Pin 46 voltage to hold PB V Pin 17 voltage to hold REC V Pin 17 voltage to hold REC V Pin 45 voltage to hold HSW V Pin 45 voltage to hold HSW V Pin 18 voltage to hold RECGATE V Pin 18 voltage to hold RECGATE BH7272KV = 0.3mV IN P-P P-P = 300mV IN P-P P-P 3 ...
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... DET AGC BH7272KV Balance IAMP 10k 10k PRE Fig. 1 BH7272KV LIMIT LEVEL adj 24 LIMIT 23 LIMIT Vth adj 22 21 VAMP 20 Vcc 4.9V 19 Balance 18 REC GATE BF 17 REC “H” Bias Vcc 3.0V 16 0.1 15 IAMP ...
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... REC OUT B Fig LIMIT VAMP 20 19 Balance Bias 16 0.1 15 IAMP IAMP 14 PRE REC OUT A BH7272KV LIMIT LEVEL adj LIMIT Vth adj Vcc 4.9V REC GATE REC “H” Vcc 3V Vcc 4.9V I0adj 5 ...
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... Operation MUTE OFF MUTE ON — Operation AGC detection on AGC detection off — BH7272KV Circuit operation REC-B PB PB-A PB Operating : Power save state 1 1 ...
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... HEAD B REC DC feedback GND for PB 1st stage amplifier and — REC current amplifier 1k 1st stage amplifier positive phase output 10k PB feedback 1st stage amplifier reverse phase output 10k PB feedback 7 1k GND for REC current amplifier — BH7272KV Function 7 ...
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... Equivalent internal circuit 20 REC DC feedback 5k HEAD HEAD A 5k REC DC feedback 12.8k 13 12.8k HEAD A recording current adjustment 2.5k 400 V — 25k Bias filter for head connection pins 15 (pins 2, 3, 10, and 11) 25k V — BH7272KV Function for REC current amplifier CC for logic circuits CC ...
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... GND for bias and control logic 400 500 REC limiter amplifier positive phase 21 output 400 400 500 REC limiter amplifier reverse phase 22 output 400 35k REC limiter amplifier input threshold 23 level adjustment 15k BH7272KV Function for bias and REC limiter amplifier CC 9 ...
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... BH7272KV Function REC limiter amplifier output level adjustment REC input GND for REC limiter amplifier Playback system AGC output Playback system AGC detector input Playback system AGC level adjustment Playback system AGC filter Playback system AGC input ...
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... Playback system mute control 100k — Playback system amplifier output 35 36 GND for PB amplifier, AGC, and peak — amplifier — V amplifier Playback system 2nd amplifier output 380 Playback system 2nd amplifier output 39 40 BH7272KV Function — for PB amplifier, AGC, and peak CC 11 ...
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... Playback system 2nd amplifier input 80 Playback system 2nd amplifier input 1st stage amplifier positive phase 43 output 1k 1st stage amplifier reverse phase 44 output 15k 45 Mode control 100k 15k 46 Mode control 100k — — V 12.8k 48 12.8k HEAD B recording current adjustment 2.6k 400 BH7272KV Function for PB 1st stage amplifier CC ...
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... DET AGC BH7272KV Balance IAMP 10k 10k PRE HEAD B Fig. 3 BH7272KV LIMIT LEVEL adj LIMIT LIMIT Vth adj VAMP 20 19 Vcc 4.9V Balance REC GATE REC “H” Bias 16 Vcc 3.0V 0.1 15 ...
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... Video ICs • External dimensions (Units: mm) 9.0 0.3 7.0 0 0.5 0.2 0.1 VQFP48 14 0.125 0.1 0.10 BH7272KV ...