Video ICs 4-channel PRE / REC amplifier with auto-tracking interface BA7184S The BA7184S is a PRE / REC amplifier developed for use in video cassette recorders. It is compatible with four-head decks and features built-in FB damping, four preamplifiers, a chroma output amplifier, an FM output amplifier (with AGC), an envelope detector and envelope comparator, a constant-current BTL-drive REC amplifier (with AGC) and channel switching, EP / SP switching, and mode switching integrated onto a single monolithic IC. Applications •VCRs •1)Features The playback amplifier has a total gain of 56dB (Typ.), and has a low-noise preamplifier. Designed for VHS band operation with low external parts count. The IC has 4 circuits for 4-head VCR applications. 2) Two playback output systems (through output and AGC output). The AGC output level is 315mV P-P (Typ.); suitable for FM brightness signal output. 3) Auto-tracking interface for automated tracking adjustment. Linear detector characteristic with sensitivity that can be set using external components. 4) The recording amplifier uses constant-current BLT drive that handles load variations (i.e. headimpedance) well, and gives stable recording characteristics. 2 circuits are provided for 4-head VCR use. 5) Built-in recording level AGC means adjustment of FM recording current is not necessary. 6) Head switches for 4-channel PRE / REC system provided. 7) Operates off a single 5V power supply, with low power dissipation. •Absolute maximum ratings (Ta = 25°C) Parameter Applied voltage Power dissipation Symbol Limits Unit VCC 7.0 V 1050∗1 Pd mW Operating temperature Topr – 20 ~ + 65 °C Storage temperature Tstg – 55 ~ + 125 °C ∗1 Reduced by 10.5mW for each increase in Ta of 1°C over 25°C (free air). •Recommended operating conditions (Ta = 25°C) Parameter Symbol Min. Typ. Max. Unit Conditions Playback / recording VCC 4.5 5.0 5.5 V 13pin 䊊 Not designed for radiation resistance. 1 Video ICs BA7184S •Block diagram 24 23 22 21 RF 20 19 18 AT ENVE OUT 17 H SYNC IN DET AGC AT ENVE PEAKING DET PRE ENVE PEAK ENVE PRE LOGIC PRE 15 14 13 EP 16 REC AGC SP REC IN VCC 12 ENVE COMP OUT MUTE 11 TP / PB / EE / REC CTRL DFF IN COMP 10 REC DCFB 2 ENVE PRE IN 4 (REC - OUT 4) PRE REC + OUT 2 9 2 PB RF OUT 8 PRE IN 3 (REC - OUT 3) PB AGC OUT 7 GND 1 PB AGC FILTER (REC DCFB 1) 6 PRE IN 2 (REC - OUT 2) 5 REC + OUT 1 4 PRE IN 1 (REC - OUT 1) REC LEVEL ADJ 3 REC AGC FILTER GND 2 2 EP / SP CTRL 1 AT ENVE FB VCC Video ICs BA7184S •Electrical characteristics (unless otherwise noted, Ta = 25°C, V CC Parameter = 5.0V and f = 4.0MHz) Conditions Measurement circuit Symbol Min. Typ. Max. Unit Iq (P) — 27 45 mA No signal Fig. 1 Fig. 1 〈Playback system〉 (Pin 12: H) Supply current Voltage gain ch-1 GVP1 52 56 60 dB Pin 4 input = 0.3mVP-P, pin 2: L, pin 16: L, pin 20 output measurement Voltage gain ch-2 GVP2 52 56 60 dB Pin 6 input = 0.3mVP-P, pin 2: L, pin 16: H, pin 20 output measurement Fig. 1 Voltage gain ch-3 GVP3 52 56 60 dB Pin 8 input = 0.3mVP-P, pin 2: H, pin 16: L, pin 20 output measurement Fig. 1 Voltage gain ch-4 GVP4 52 56 60 dB Pin 10 input = 0.3mVP-P, pin 2: H, pin 16: H, pin 20 output measurement Fig. 1 Voltage gain differential ∆GVP – 1.5 — + 1.5 dB ∆GVP = GVP1 – GVP2, GVP3 – GVP4 Fig. 1 dB Pin 20 output level difference for f = 8.0 / 1.0MHz, VIN = 0.3mVP-P. Fig. 1 ∆GVf –8 – 1.7 — 2nd harmonic distortion 2HDP — – 42 – 35 dBc VIN = 0.3mVP-P, 8.0MHz spurious Fig. 1 3rd harmonic distortion 3HDP — – 50 – 35 dBc VIN = 0.3mVP-P, 12.0MHz spurious∗2 Fig. 1 Maximum output level VOMP 0.8 1.2 — VP-P When pin 20 output 2nd harmonic distortion is – 30dBc Fig. 1 Crosstalk CTP — – 45 – 30 dBc Pin 20 output level difference for pin 2: H / L, pin 16: H / L. Fig. 1 ∆VODC — — 200 mVP-P Pin 20 output DC offset for pin 2: H / L, pin 16: H / L. Fig. 1 Input conversion noise VNIN — 0.25 1.0 µVrms Rg = 10Ω, input conversion of pin 20 output noise∗2 Fig. 1 AGC output level VAGC 265 315 365 mVP-P VIN = 0.3mVP-P, pin 21 output measurement Fig. 1 ∆VAGC — 0.3 2.0 dB Pin 21 output level differential for VIN = 0.15 to 0.6mVP-P. Fig. 1 Fig. 1 Frequency characteristic Output DC offset AGC control sensitivity AGC frequency characteristic ∆GVAF –8 –3 — dB f = 8.0 / 1.0MHz, VIN = 0.3mVP-P∗2 PB switch ON resistance RON5, 9 — 5 10 Ω Pin 5 and pin 9 impedance∗2 Fig. 1 ENVE residual voltage VENV1 — 0.7 1.0 V Pin 18 output measurement when no signal Fig. 1 ENVE output level VENV2 2.4 2.9 3.4 V Pin 18 output measurement when pin 20 output = 400mVP-P Fig. 1 ENVE saturation voltage VENV3 4.0 4.5 — V Pin 18 output measurement for large signal Fig. 1 PRE ch 2 and 4 holding voltage VTH16H 3.5 — VCC V Pin 16 DC voltage for ch 2 and 4 operation Fig. 1 PRE ch 1 and 3 holding voltage VTH16L 0 — 1.2 V Pin 16 DC voltage for ch 1 and 3 operation Fig. 1 EP mode holding voltage VTH2H 3.5 — VCC V Pin 2 DC voltage for EP mode Fig. 1 SP mode holding voltage VTH2L 0 — 1.2 V Pin 2 DC voltage for SP mode Fig. 1 TP mode holding voltage VTH12T 4.1 — VCC V Pin 12 DC voltage for TRICK PLAY mode Fig. 1 PB mode holdihg voltage VTH12H 3.0 — 3.7 V Pin 12 DC voltage for PB mode Fig. 1 EE mode holding voltage VTH12M 1.1 — 2.6 V Pin 12 DC voltage for REC MUTE mode Fig. 1 REC mode holding voltage VTH12L 0 — 0.7 V Pin 12 DC voltage for REC mode Fig. 1 ∗ 2 Guaranteed design values. Note: dBc: dB below carrier (used to express relative level from carrier reference for convenience sake) 3 Video ICs Parameter BA7184S Symbol Min. Typ. Max. Unit Iq (R) — 67 100 mA Conditions Measurement circuit 〈Recording system〉 (Pin 12: L) Quiescent current No signal Fig. 2 Fig. 2 Recording AGC level 1 IOAR1 27 30 33 mAP-P Pin 14 input = 125mVP-P, pin 2: L, pin 5 output measurement Recording AGC level 2 IOAR2 24 27 30 mAP-P Pin 14 input = 125mVP-P, pin 2: H, pin 9 output measurement Fig. 2 AGC control sensitivity ∆IOAR — 0.3 2.0 dB Pin 14 input = 62.5mVP-P, to 250mVP-P, pin 5 output level differential Fig. 2 AGC frequency characteristic ∆IOAF –8 –3 — dB f = 8.0 / 1.0MHz, pin 14 input = 125mVP-P,∗2 Fig. 2 2nd harmonic distortion 2HDR — – 45 – 35 dBc Pin 14 input = 125mVP-P, 8MHz spurious Fig. 2 3rd harmonic distortion 3HDR — – 50 – 35 dBc Pin 14 input = 125mVP-P, 12.0MHz spurious∗2 Fig. 2 Cross modulation distortion CMDR — – 50 – 35 dBc 4.0MHz ± 630kHz spurious∗2 Fig. 2 When pin 5 output 2nd harmonic distortion is – 30dB Fig. 2 Fig. 2 Maximum output level IOMR 40 50 — mAP-P Recording current load characteristic ∆IORL – 2.0 – 0.3 — dB Pin 5 output level difference when load L: 8.2 and 12µH∗2 Mute attenuation ratio MUR — – 45 – 35 dBc Pin 5 output level difference for pin 12: M / L Fig. 2 AGC mode holding voltage VTH17H 2.8 — VCC V Pin 17 DC voltage to maintain recording AGC operation. Fig. 2 AGC mode holding voltage VTH17L 0 — 1.2 V Pin 17 DC voltage to maintain recording AGC stopped. Fig. 2 ∗2 Guaranteed design values. Note: dBc: dB below carrier (used to express relative level from carrier reference for convenience sake) 4 8 9 COMP MUTE SP 10 11 REC MUTE ‘‘L’’ 7 14 TRICK PLAY ‘‘H’’ PB: OPEN PRE 0.1µ ENVE 15 REC START ‘‘L’’ LOGIC 0.1µ PRE 16 1k 6 17 PRE IN 4 18 10 5 0.1µ 4 10 PRE PRE IN 3 RF 0.1µ 3 AGC 19 1k PEAK ENVE 20 1k DET 21 PRE IN 2 22 10 0.1µ 10 2 PRE IN 1 1 0.1µ 23 1k 10k 24 EP / SP CTRL 33k 0.01µ 390k 68p 22µ 3.9k 0.1µ 33k REC IN ENVE COMP OUT DFF IN H SYNC IN AT ENVE OUT AT ENVE PEAKING PB RF OUT PB AGC OUT Video ICs BA7184S Measurement circuits •(Playback system) + VCC 5V 13 REC VCC ENVE AGC EP DET PRE 12 Units: R [Ω] C [F] L [H] Fig. 1 5 6 Fig. 2 PRE 7 16 ENVE PRE 8 COMP MUTE 15 9 14 RF SP 10 11 Units: R [Ω] C [F] L [H] REC MUTE ‘‘L’’ LOGIC TRICK PLAY ‘‘H’’ PB: OPEN 6 17 0.1µ 5 18 REC START ‘‘L’’ 4 19 8.2µ PEAK ENVE 0.1µ PRE REC OUT 2 AGC 0.1µ 3 20 10 21 8.2µ DET 8.2µ 22 0.1µ 2 0.1µ 23 10 0.1µ 1 8.2µ 10k 24 REC OUT 1 EP / SP CTRL 33k 0.01µ 390k 68p 22µ 3.9k 0.1µ 33k REC IN ENVE COMP OUT DFF IN H SYNC IN AT ENVE OUT PB RF OUT PB AGC OUT REC LEVEL ADJ Video ICs BA7184S (Recording system) + VCC 5V VCC 13 REC ENVE AGC EP DET PRE 12 Video ICs BA7184S system logic table •(1)Control DFF IN (pin 16) • Playback input selection (head switching) Function Control pin DFF IN EP / SP L H H L L H Selected playback input Control voltage VCTRL16 [V] Ch3 (PRE IN3 8pin) 3.5 ~ VCC Ch4 (PRE IN4 10pin) 0.0 ~ 1.2 Ch1 (PRE IN1 4pin) — Ch2 (PRE IN2 6pin) — (2) EP / SP control (pin 2) • Recording output selection • Playback input selection (see (1)) Control pin EP / SP Function Control voltage VCTRL2 [V] Selected recording output H EP (REC OUT 8, 9, 10pin) 3.5 ~ VCC L SP (REC OUT 4, 5, 6pin) 0.0 ~ 1.2 (3) TP / PB / EE / REC CTRL (pin 12) • Special playback / playback / recording mute / recording mode switching Control pin Function Mode PRE AMP AT ENVE ENV COMP REC MUTE REC AMP PB / EE / REC OT ON TRICK PLAY ON Control voltage VCTRL12 [V] ON OFF OFF 4.1 ~ VCC H PB ON ON OFF OFF OFF 3.0 ~ 3.7 M REC MUTE OFF OFF OFF ON ON 1.1 ~ 2.6 L REC OFF OFF OFF OFF ON 0.0 ~ 0.7 • Pin 12 is biased internally in the IC. When open, PB mode is selected. (4) H SYNC IN (pin 17) • Special playback envelope comparator (ENVE COMP) output latch control. • AGC operation control for recording. Control pin Function Control voltage VCTRL17 [V] H SYNC ENVE COMP H Set at falling edge ON 2.8 ~ VCC L — OFF 0.0 ~ 1.2 AGC detector (5) ENVE COMP OUT (pin 15) • Outputs playback envelope comparator data for special playback. Control pin Function ENVE COMP Playback input level H Ch1 or Ch2 > Ch3 or Ch4 L Ch1 or Ch2 < Ch3 or Ch4 7 Video ICs BA7184S 24 23 22 21 20 AGC RF DFF IN ENVE COMP OUT REC Y IN REC C IN 19 18 PEAK ENVE + 0.01µ 390k VCC 5V 68p 22µ DET H SYNC IN AT ENVE OUT AT ENVE PEAKING PB RF OUT 3.9k 33k 0.1µ REC LEVEL ADJ PB AGC OUT •Application example 17 16 LOGIC 15 14 13 COMP MUTE VCC REC AGC ENVE ENVE EP SP PRE PRE PRE PRE DET 6 7 • 22.9 ± 0.3 24 13 1 12 6.5 ± 0.3 0.51Min. 3.4 ± 0.2 3.95 ± 0.3 10 11 7.62 0.3 ± 0.1 0.5 ± 0.1 SDIP24 0° 12 ~ 15° Units: R [Ω] C [F] L [H] PB: OPEN 0.1µ TRICK PLAY ‘‘H’’ A B EP HEAD Fig. 3 8 9 0.1µ 0.1µ A B SP HEAD External dimensions (Units: mm) 1.778 8 0.1µ 5 0.1µ EP / SP CTRL 33k 10k AT ENVE GAIN EP ‘‘H’’ 4 0.1µ 3 REC MUTE ‘‘L’’ 2 REC START ‘‘L’’ 1 33k