Video ICs 2-channel PRE / REC amplifier with auto-tracking interface BA7182AS The BA7182AS is a PRE / REC amplifier developed for use in video cassette recorders. It has been designed for use in two-head decks and features built-in FB damping, two preamplifiers, a chroma output amplifier, an FM output amplifier (with AGC), an envelope detector, a constant-current BTL-drive REC amplifier (with AGC) and built-in channel and REC / PB switches on a single monolithic IC. Applications •VCRs •1)Features The playback amplifier has a total gain of 59dB (Typ.), and has a low-noise preamplifier. Designed for VHS-band operation with low external parts count. The IC has 2 circuits for 2-head VCR applications. 2) Two playback output systems (throgh output and AGC output). The AGC output level is 270mV P-P (Typ.) ; suitable for FM brightness signal output. 3) Auto-tracking interface for automated tracking adjustment. An integrate and hold detector is used to reduce the load on the microcontroller. 4) The recording amplifier uses constant-current BLT drive that handles load variations (i.e. headimpedance) well, and gives stable recording characteristics. A single circuit is provided for 2-head VCR use. 5) Built-in recording level AGC means adjustment of FM recording current is not necessary. 6) Head switches for 2-channel PRE / REC system provided. 7) Operates off a single 5V power supply, with low power dissipation. •Absolute maximum ratings (Ta = 25°C) Symbol Parameter Limits Unit Applied voltage VCC 7.0 V Power dissipation Pd 1100∗ mW Operating temperature Topr – 20 ~ + 75 °C Storage temperature Tstg – 55 ~ + 125 °C ∗ Reduced by 11mW 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 12pin 䊊Not designed for radiation resistance. 1 Video ICs BA7182AS •Block diagram 22 GND 2 DET FILTER 2 21 EP / SP CTRL HOLD FILTER 3 20 AT ENVE HOLD OUT REC DCFB 4 19 AT ENVE DET ADJ 18 PB RF OUT 17 PB AGC FILTER 16 REC IN 15 PB / EE / REC CTRL 14 PB AGC OUT 13 REC EQ 12 VCC DET S/H 1 HPF DFF IN – DET 6 8 REC AGC FILTER 9 REC LEVEL ADJ 10 H SYNC IN 11 LOGIC PRE / REC – + OUT REC AGC 7 HPF PRE PRE IN 2 (REC – OUT 2) 5 RF GND 1 PRE PRE IN 1 (REC – OUT 1) + MUTE REC 1k AGC DET VCC 2 Video ICs BA7182AS •Electrical characteristics (unless otherwise noted, Ta = 25°C, V CC Parameter Symbol Min. Typ. Max. = 5.0V and f = 4.0MHz) Unit Conditions Measurement circuit 〈Playback system〉 (Pin 15: H) — 26 42 mA No signal Fig.1 GVP1 56.5 59 61.5 dB Pin 5 input = 0.3mVP-P, pin 1: L, pin 18 output measurement Fig.1 Voltage gain ch-2 GVP2 56.5 59 61.5 dB Pin 7 input = 0.3mVP-P, pin 1: H, pin 18 output measurement Fig.1 Voltage gain differential ∆GVP –1 0 1 dB ∆GVP = GVP1 – G VP2 Fig.1 Frequency characteristic ∆GVf –6 –3 –1 dB Difference in pin 18 output level for f = 8.0 / 1.0MHz, VIN = 0.3mVP-P Fig.1 2nd harmonic distortion 2HDP — dBc VIN = 0.3mVP-P, 8.0MHz spurious Fig.1 dBc VIN = 0.3mVP-P, 12.0MHz spurious, guaranteed design value. Fig.1 — VP-P When pin 18 output 2nd harmonic distortion is – 30dBc Fig.1 – 38 – 33 dBc Difference in pin 18 output level for pin 1: H / L. Fig.1 mVP-P Pin 18 output DC offset for pin 1: H / L. Fig.1 Rg = 10Ω, input conversion of pin 18 output noise, guaranteed design value. Fig.1 Quiescent current Iq Voltage gain ch-1 (P) 3rd harmonic distortion 3HDP — Maximum output level VOMP 1.0 Crosstalk CTP — Output DC offset ∆VODC – 150 – 45 – 35 – 50 – 35 1.5 0 150 VNIN — 0.25 1.0 µVrms AGC output level VAGC 220 270 320 mVP-P VIN = 0.3mVP-P Pin 14 output measurement Fig.1 AGC control sensitivity ∆VAGC — 0.3 2 dB Pin 14 output level difference for VIN = 0.15 and 0.6mVP-P Fig.1 2 dB Difference in pin 14 output level for f = 8.0 / 1.0MHz VIN = 0.3mVP-P. Fig.1 Input conversion noise AGC frequency characteristic ∆GVAF –2 0.5 PB switch ON resistance RON8 — 5 10 Ω Pin 8 impedance Fig.1 PRE ch 2 holding voltage VTH1H 3.5 — VCC V Pin 1 DC voltage for ch 2 operation Fig.1 PRE ch 1 holding voltage VTH1L 0 — 1.2 V Pin 1 DC voltage for ch 1 operation Fig.1 ENVE output level SP-2 VEN-S2 1.4 2.2 3.0 V Pin 20 output measurement when pin 21 = L and pin 18 output = 250mVP-P Fig.1 ENVE sensitivity curve PCRV 150 200 250 % 4.6 4.9 — V Pin 21 = L, Pin 20 output measurement for large signal Fig.1 ENVE saturation voltage VEN-MA — Fig.1 VEN-MI — 0.1 0.4 V Pin 21 = L, Pin 20 output measurement for no signal Fig.1 EP mode holding voltage VTH21H 3.5 — VCC V Pin 21 DC voltage for EP mode Fig.1 SP mode holding voltage VTH21L 0 — 1.2 V Pin 21 DC voltage for SP mode Fig.1 ENVE residual voltage 3 Video ICs BA7182AS (unless otherwise noted, Ta = 25°C, VCC = 5.0V, f = 4.0MHz and IOAR = 36mAP-P) Parameter Symbol Min. Typ. Max. Unit Conditions Measurement circuit 〈Recording system〉 (Pin 15: L) Quiescent current Iq (R) — 72 108 mA Recording AGC level IOAR 30 36 42 mAP-P No signal Fig.2 Pin 16 input = 400mVP-P, pin 8 output measurement Fig.2 Fig.2 AGC control sensitivity ∆IOAR — 0.15 2 dB Pin 8 output level difference for f = 4.0MHz, pin 16 input = 225mVP-P to 800mVP-P. AGC frequency characteristic ∆IOAF –2 0 2 dB Pin 8 output level difference for f = 8.0 / 1.0MHz, pin 16 input = 400mVP-P Fig.2 2nd harmonic distortion 2HDR — – 41 – 35 dBc Pin 16 input = 400mVP-P, 8.0MHz spurious. Fig.2 Fig.2 3rd harmonic distortion 3HDR — – 50 – 40 dBc Pin 16 input = 400mVP-P, 12.0MHz spurious, guaranteed design value. Cross modulation distortion CMDR — – 43 – 38 dBc 4.0MHz ± 630kHz spurious, guaranteed design value. Fig.2 When pin 8 output 2nd harmonic distortion is – 30dB Fig.2 Pin 8 output level difference for load L: 8.2 ~ 12µH Fig.2 Fig.2 Maximum output level IOMR 42 Recording current load characteristic ∆IORL –2 Mute attenuation ratio MUR — Frequency characteristic ∆IOEQ – 5.3 AGC mode holding voltage VTH11H 2.7 AGC mode holding voltage VTH11L 0 50 — mAP-P — dB – 44 – 38 dBc Pin 8 output level difference for pin 15: M / H. – 7.8 – 10.3 dB Pin 8 output level difference for f = 8.0 / 1.0MHz, AGC OFF Fig.2 — VCC V Pin 11 DC voltage to maintain recording AGC operation Fig.2 — 1.2 V Pin 11 DC voltage to maintain recording AGC stopped Fig.2 Fig.2 – 0.35 PB mode holding voltage VTH15H 3.8 — VCC V Pin 15 DC voltage for PB mode EE mode holding voltage VTH15M 2.2 — 2.8 V Pin 15 DC voltage for REC MUTE mode Fig.2 REC mode holding voltage VTH15L 0 — 1.2 V Pin 15 DC voltage for REC mode Fig.2 ∗ Note: dBc: dB below carrier (used to express relative level from carrier reference for convenience sake) 4 Video ICs BA7182AS Measurement circuits •(Playback system) DFF IN 1 22 2 21 EP / SP CTRL L: SP 20 AT ENVE HOLD OUT 0.1µ 0.1µ S/H DET HPF 3 0.1µ PRE IN 1 19 4 AT ENVE DET ADJ 1k – 2.0V 0.1µ PRE 5 18 PB RF OUT 10 0.1µ DET RF 6 17 0.1µ AGC 7 HPF PRE 10 16 REC IN 0.1µ 0.1µ 8 14 PB AGC OUT 3k MUTE 36k REC DET 10 0.1µ 1k AGC 0.01µ 13 0.022µ VCC 390k H SYNC IN L: REC MUTE L: REC START 9 REC LEVEL ADJ 15 + 0.1µ PB / EE / REC CTRL 33k LOGIC 1k PRE / REC – PRE IN 2 11 68p 12 300 + VCC 5V Units: R [Ω] C [F] L [H] Fig. 1 5 Video ICs BA7182AS (Recording system) DFF IN 1 22 2 21 EP / SP CTRL L: SP 20 AT ENVE HOLD OUT 0.1µ 0.1µ S/H DET HPF 3 0.1µ 19 4 AT ENVE DET ADJ – 2.0V 0.1µ PRE 5 18 PB RF OUT 8.2µ 0.1µ DET RF 6 17 0.1µ L: REC MUTE L: REC START 14 9 3k MUTE 36k REC DET 10 PB AGC OUT 0.1µ 1k AGC 0.01µ REC LEVEL ADJ PB / EE / REC CTRL 15 + 0.1µ 33k LOGIC 8 13 0.022µ VCC 390k H SYNC IN REC IN 0.1µ PRE / REC 10 16 0.1µ – REC OUT AGC 7 HPF PRE 8.2µ 11 68p 12 300 + VCC Units: R [Ω] C [F] L [H] Fig. 2 6 5V Video ICs BA7182AS mode tables •(1)Control DFF IN (pin 1) • Playback input selection (head switching) • Playback output envelope detection timing control (integrate and hold one frame) Control pin Function Control voltage VCTRL1 [V] DFF IN Selected playback input H Ch2 (PRE IN2 7pin) Reset on rising edge 3.5 ~ VCC L Ch1 (PRE IN1 5pin) — 0.0 ~ 1.2 Envelope detect (2) H SYNC IN (pin 11) • Controls recording AGC detector block operation. Control pin Function H SYNC AGC detect H ON 2.7 ~ VCC L OFF 0.0 ~ 1.2 Control voltage VCTRL11 [V] (3) PB / EE / REC CTRL (pin 15) • Playback / recording mute / recording mode switching Control pin PB / EE / REC ∗ Mode Function PRE AMP AT ENVE REC MUTE REC AMP Control voltage VCTRL15 [V] H PB ON ON OFF OFF 3.8 ~ VCC M REC MUTE OFF OFF ON ON 2.2 ~ 2.8 L REC OFF OFF OFF ON 0.0 ~ 1.2 Pin 15 is pulled up to VCC via a 33kΩ resistor. (4) EP / SP CTRL (pin 21) • Switching for the detector gain of the playback envelope detector. ∗ Control pin Function EP / SP AT ENVE gain Control voltage VCTRL21 [V] H Typ. + 6dB 3.5 ~ VCC L Typ. 0.0 ~ 1.2 Pin 21 is pulled up to VCC via a 50kΩ resistor. 7 Video ICs BA7182AS •Application example DFF IN 1 22 2 21 EP / SP CTRL L: SP 20 AT ENVE HOLD OUT 0.1µ 0.1µ S/H DET HPF 3 0.1µ 4 (2.0V) 19 91k AT ENVE DET ADJ 110k – 0.1µ PRE 5 PB RF OUT 18 0.01µ HEAD A DET RF 6 17 0.1µ HEAD B AGC HPF PRE 7 REC IN 16 0.1µ L: REC START 9 0.01µ 13 100p VCC 390k H SYNC IN MUTE 36k REC 1k AGC 10 PB AGC OUT 14 DET REC LEVEL ADJ PB / EE / REC CTRL L: REC MUTE 15 + 0.1µ LOGIC PRE / REC – 8 0.01µ 33k 11 12 + VCC Units: R [Ω] C [F] L [H] Fig. 3 8 5V Video ICs BA7182AS •External dimensions (Units: mm) 19.4 ± 0.3 12 6.5 ± 0.3 0.51Min. 3.4 ± 0.2 3.95 ± 0.3 22 11 1 7.62 0.3 ± 0.1 1.778 0.5 ± 0.1 0° ~ 15° SDIP22 9