CXA1878Q Dolby∗ B-C Type Noise Reduction System with Recording/Playback Equalizer Amplifier Description The CXA1878Q is a bipolar IC with a built-in Dolby B-C type noise reduction system (NR), Dolby S type select switch, recording/playback equalizer, electronic volume, and bias control circuit. Use of this IC in combination with two CXA1417S/Q completes a Dolby B-C-S type NR stereo system. Features • Dolby B-C type NR • Built-in filter required for recording/playback equalizer amplifiers • Recording mute function (requiring only an external time constant circuit to implement soft mute) • Fade in/out DC controllable • NORM/CrO2/METAL tape mode switching function • NORM/HIGH tape speed switching function • DC controllable for recording level calibration (approximately ±6dB variable) • DC controllable for high frequency equalizer amplifier gain (approximately ±4dB variable) • Playback deck A/B select switch • Recording volume control • Bias control circuit • Meter circuit 64 pin QFP (Plastic) Structure Bipolar silicon monolithic IC Absolute Maximum Ratings • Supply voltage VCC 17 V • Operating temperature Topr –20 to +75 °C • Storage temperature Tstg –65 to +150 °C • Allowable power dissipation PD 1020 mW Operating Conditions Supply voltage (VCC • VEE) ±6.5 to 8.0 V Applications Recording/playback equalizer amplifier for stereo analog cassette decks (Applicable to ALPS ELECTRIC CO., LTD. HADKH55 series heads) ∗ These ICs are available only to the licensees of Dolby Laboratories Licensing Corporation from whom licensing and applications information may be obtained. ∗ “Dolby” and the double D symbols are trade marks of Dolby Laboratories Licensing Corporation. Sony reserves the right to change products and specifications without prior notice. This information does not convey any license by any implication or otherwise under any patents or other right. Application circuits shown, if any, are typical examples illustrating the operation of the devices. Sony cannot assume responsibility for any problems arising out of the use of these circuits. –1– E95933A5Z-PK 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 NR RECIN1 VEE LINE OUT1 METAL NORM CrO2 NR TCH1 REC-EQ NR TCL1 VOL OUT1 64 NR OUT1 VOLUME S IN1 CAL B/C S REC IN1 METER1 METER2 VOLUME CONT 33 NR RECOUT1 VOL IN1 63 PB DOLBY B-C NR CXA1878Q D GND 34 35 REC OUT1 GND REC ON METER MUTE GND MUTE S B/C CAL 36 37 DOLBY B-C NR AMS 38 IREF GND ON CAL OFF ON OFF CAL ON METER 39 40 NR IREF NR PBIN1 62 REC MOA CAL IN 41 MT C2 MT C1 PASS MUTE NR CAL REC MUTE 42 BS FB BIAS M OFF ON MOA REC PB REC-EQ REC OUT2 43 AMS FB BIAS C LINE PB EQ PB PB REC NR RECOUT2 44 AMS TC BIAS N PB OUT1 61 B DECK S IN2 GND 45 AMS OUT AMS SW (OFF/AMS/BS) PB INB1 60 A ON CAL NR MUTE PASS REC IN2 46 S SW (S/BC/CAL) PASS SW (NR/MUTE/PASS) PB INA1 59 GND PB INA2 57 PB EQ NR OUT2 47 REC CAL METER SW (ON/MUTE) –2– SPEED (NS/HS) GND 58 A PB INB2 56 OFF 50 NR RECIN2 LINE 49 LINE OUT2 VOLUME 48 NR TCH2 DECK B PB OUT2 55 NR PBIN2 54 VOL IN2 53 VOL OUT2 52 NR TCL2 51 NR SW (OFF/B/C) Block Diagram and Pin Configuration METER1 METER2 REC VOL REC BAL DGND A EQ (120µ/70µ) MODE SW 20 (REC/PB) 21 VCC 22 DVCC 23 B EQ 24 (NORM/CrO2/METAL) DECK A/B 25 (A/B) 26 27 28 29 30 31 VEE 32 GP CAL CXA1878Q CXA1878Q Pin Description Pin No. Symbol (Ta = 25°C, VCC = 7.0V, VEE = –7.0V, DVCC = 5.0V) Typical pin voltage DC AC I/O Z (in) Equivalent circuit Description GND 40k 1 51 NR RECIN1 0.0V –26dBv NR RECIN2 I 40kΩ 1.5k Recording equalizer amplifier input 1 51 300 2 50 LINE OUT1 LINE OUT2 0.0V –4dBv O — 3.4k 2 Line output 50 300 330k 3 49 NR TCH1 NR TCH2 VEE +0.4V 13k — — — 3 49 36k Time constant for the HLS 13.5k 4 48 NR TCL1 NR TCL2 VEE +0.4V — — — Time constant for the LLS 4 48 –3– 480k CXA1878Q Pin No. Symbol 5 47 NR OUT1 NR OUT2 Typical pin voltage DC AC I/O Z (in) Equivalent circuit 192 –6dBm 0.0V (–7dBv) O — Description 12k 5 20k 47 192 Dolby S type NR output 1.5k GND 6 46 S IN1 S IN2 0.0V –6dBm (–7dBv) I 6 40kΩ Dolby S type NR input 46 40k GND 9.5k 7 45 REC IN1 REC IN2 0.0V –24dBv I 50kΩ Recording equalizer amplifier input 7 45 50k GND 211 8 44 NR RECOUT1 NR RECOUT2 –6dBm 0.0V (–7dBv) O — 22.5k 8 44 211 1.5k GND –4– Dolby NR recording signal output CXA1878Q Typical pin voltage Pin No. Symbol 9 43 REC OUT1 REC OUT2 DC AC I/O Z (in) Equivalent circuit 200 0.0V –3dBv O — Description 50k Recording equalizer amplifier output 9 43 200 Reference current setting for built-in recording/playback equalizer amplifier ∗ The reference current can be set by connecting a resistor between this pin and VEE. 192 10 IREF VEE +1.2V — — 10 — 6k 8k 11 NR IREF 12 40 MT C1 MT C2 VEE +1.2V — — — 40k Reference current setting for built-in Dolby NR ∗ The reference current can be set by connecting a resistor between this pin and VEE. 11 300 0.0V — O — 14k DC cut capacitance 12 40 –5– 300 CXA1878Q Pin No. 13 14 15 Symbol BIAS M BIAS C BIAS N Typical pin voltage DC AC — — I/O Z (in) O — Equivalent circuit Description Recording bias control voltage output 13 14 15 100k 16 AMS SW 2.5V when open — I — 50k 5k 16 5k 24k 17 PASS SW 2.5V when open — I — 50k DGND AMS mode control ∗ Mode select switch for AMS/BS amplifier High: BS mode Medium: AMS mode Low: AMS/BS OFF mode [BS mode = Music signal interval detection during playback] [AMS mode = Music signal detection during FF/REW] PASS mode control H : PASS M : MUTE L : NR ON 5k 17 5k DGND 10k 18 METER SW — — I — 18 DGND –6– Meter mode control ∗ Meter amplifier output ON/OFF select switch High: Meter output OFF (mute) Low : Meter output ON CXA1878Q Pin No. Typical pin voltage Symbol DC AC I/O Z (in) Equivalent circuit Description Tape speed selection ∗ Normal speed/ double speed selection High: Double speed Low : Normal speed 10k 19 SPEED — — I — 19 10k DGND 2k — — I — VCC 7.0V — I — Positive power supply DVCC 5.0V — I — Reference power supply for mode control — Deck A playback equalizer amplifier control ∗ 120µs/70µs selection High: 70µs Low : 120µs (Built-in equalizer amplifier flat) 20 MODE SW 21 22 23 Recording/playback mode control ∗ Recording/playback mode selection High : Recording mode Low : Playback mode 6k A EQ 2.5V when open — I 20 23 10k DGND 24 B EQ 2.5V when open — I — 10k 24 DGND –7– Control of deck B playback equalizer amplifier mode, recording equalizer amplifier mode, and recording bias mode ∗ NORM/CrO2/METAL selection High : METAL Medium : CrO2 Low : NORM CXA1878Q Pin No. 25 Typical pin voltage Symbol DECK A/B DC — AC — I/O I Z (in) Equivalent circuit Description 10k — 25 DGND 26 27 METER1 METER2 60k 1.6V –1.1dBv O — 26 Level meter amplifier output 10k 27 Recording volume level control High: Output signal level increased Low : Output signal level reduced 60k 28 REC VOL — — I 100kΩ Playback deck A/B select control ∗ Playback equalizer amplifier input selection High: PB INB Low : PB INA 28 40k GND 8k 29 REC BAL 2.5V when open 70k — I 100kΩ 29 30k DVCC/2 30 DGND 8k 21k Recording volume balance control High : Only VOL OUT2 output level reduced Low : Only VOL OUT1 output level reduced ∗ Neither VOL OUT1 nor 2 output levels are attenuated at the control voltage of 2.5V. Connect to GND. 0.0V –8– CXA1878Q Pin No. 31 32 33 34 Symbol VEE GP CAL Typical pin voltage DC AC I/O Z (in) Equivalent circuit Description –7.0V Negative power supply 2.5V when open Recording equalizer amplifier high frequency calibration ∗ Controlled with DC voltages of 0 to 5V. High: High frequency level gain increased Low : High frequency level gain reduced ∗ Leave this pin open when not using the high frequency calibration function. REC CAL 2.5V when open NR SW 2.5V when open 54k — I 54kΩ 32 Recording equalizer amplifier calibration ∗ Controlled with DC voltages of 0 to 5V. High: Recording level gain increased Low : Recording level gain reduced ∗ Leave this pin open when not using the recording calibration function. 54k — I 54kΩ 33 2k — I 50kΩ 6k 34 50k NR control High: C type Medium: B type Low: NR OFF DVCC/2 35 S SW 2.5V when open 2k — I 50kΩ 35 50k DVCC/2 –9– 6k Dolby S type selection ∗ Select the calibration mode with this pin. High: CALIBRATION Medium: B-C type Low: S type CXA1878Q Pin No. Symbol 36 AMS OUT Typical pin voltage DC AC 0.0V — I/O Z (in) O — Equivalent circuit Description AMS amplifier output 36 10k 10k DGND 10k 37 37 AMS TC 0.0V — — — 1k 40k Time constant for the AMS 2p 38 AMS FB 0.0V — — — 38 100k Feedback during AMS mode 2p 39 BS FB 0.0V — — — 39 100k – 10 – Feedback during BS mode CXA1878Q Pin No. Typical pin voltage Symbol DC AC I/O Z (in) Equivalent circuit GND 1.5k 10k 41 CAL IN 0.0V –26dBv I 10kΩ Description 41 Calibration signal input Recording mute ON/OFF selection ∗ The recording mute is controlled with DC voltages of 0 to 5V. 30k 42 REC MUTE — — I — 42 GND High: Recording mute OFF Low : Recording mute ON ∗ Soft mute and fader functions can be set by changing the time constant of the external time constant circuit. 500 64 52 VOL OUT1 VOL OUT2 0.0V –10dBv O 64 52 63 53 VOL IN1 VOL IN2 0.0V –10dBv I 5p 50kΩ 63 53 – 11 – 500 6.5k Recording volume amplifier output Recording volume amplifier input CXA1878Q Pin No. Symbol Typical pin voltage DC AC I/O Z (in) Equivalent circuit Description Dolby NR playback input 35.5k 62 54 NR PBIN1 NR PBIN2 0.0V –11dBv I 40kΩ 2.9k 62 54 GND 61 55 PB OUT1 PB OUT2 0.0V –11dBv I — 4k 5k 500 8p 500 30k 61 55 GND Playback equalizer amplifier output GND 59 59 60 57 56 PB INA1 PB INB1 PB INA2 PB INB2 0.0V –31dBv 58 GND 0.0V 60 I 50kΩ 57 56 — — — 50k Playback equalizer amplifier input Ground – 12 – S1 S2 S3 S4 S5 R3 50k Oscilloscope Distortion Analyzer AC Voltmeter CCIR 1kHz BPF DIN Audio “A” WTG GND GND S6 R6 100 R7 100 R4 100 R5 100 VEE S7 S8 S9 S10 C7 0.1µ ∗ R25 160k ∗ R8 2.7k C1 0.1µ –11dBv C12 1.0µ –31dBv C13 0.1µ –31dBv GND C14 0.1µ –31dBv –31dBv C15 0.1µ C16 0.1µ ∗ R20 10k S11 1 VOL OUT1 ∗R30 5.1k S21 C25 4.7µ VOL IN1 PB OUT1 PB INB1 PB INA1 63 S19 C21 0.1µ PB INA2 PB INB2 PB OUT2 NR PBIN2 2 C27 0.1µ R32 2.7k C29 0.068µ 5 4 3 C33 0.1µ C31 2.2µ ∗ R34 32.1k (1M//33k) S23 6 C35 2.2µ 7 C37 4.7µ S25 ∗R36 5.1k 8 C39 2.2µ R39 2.7k S27 9 R41 2.7k R42 27k R45 27k C43 1.0µ 11 10 R46 1k I1 2mA R48 1k S38 S31 R50 1k S31 S38 S31 14 13 12 R51 1k S38 S31 15 R53 100k 16 17 18 26 25 24 23 22 21 METER1 DECK A/B B EQ A EQ DVcc Vcc 19 MODE SW 20 27 28 29 30 31 32 METER2 REC VOL REC BAL DGND VEE GP CAL 33 34 35 36 37 38 39 40 41 42 R55 1k 43 S31 R54 100k 44 C47 0.1µ 45 R52 1MEG 46 C44 1.0µ R49 10k C46 0.015µ 47 VOL IN2 C23 2.2µ C40 4.7µ R47 1k C45 1.5µ 48 NR PBIN1 64 C38 4.7µ S28 S29 ∗ R43 86k (100k// 620k) C42 2.2µ S26 ∗ R44 5.1k 49 C30 0.068µ C41 0.1µ ∗ R40 2.7k 50 VOL OUT2 GND C28 0.1µ ∗ R37 5.1k ∗ R38 2.7k 51 62 61 60 59 58 57 56 55 54 53 52 ∗ R28 86k (100k//620k) –10dBv C9 1.0µ C10 –10dBv 2.2µ –11dBv –11dBv ∗ R21 11.6k C11 (12k//330k) 0.1µ C2 0.1µ ∗R10 5.1k ∗R62 50k ∗ R9 5.1k S12 S13 C3 0.1µ ∗ R22 ∗ R12 5.1k 160k ∗ R11 2.7k ∗ R23 160k S14 ∗R24 160k S15 ∗ R13 5.1k C4 0.1µ –10dBv C18 0.1µ –10dBv C19 2.2µ C20 4.7µ ∗ R26 –11dBv 11.6k C17 (12k//330k) 1.0µ S16 ∗R14 5.1k C5 0.1µ C6 0.1µ ∗R15 5.1k ∗ R16 2.7k S17 ∗ R17 5.1k ∗R18 5.1k ∗ R27 S18 10k ∗ R61 50k C8 0.1µ ∗ R19 2.7k NR RECIN1 –26dBv Amp 0dB or 30dB C26 4.7µ LINE OUT1 –4dBv C24 2.2µ ∗ R35 32.1k (1M//33k) C32 2.2µ C36 2.2µ –7dBv ∗ R29 86k S24 C34 0.1µ S IN1 –7dBv S20 ∗ R33 2.7k REC IN1 –24dBv DC Voltmeter S22 ∗ R31 5.1k –7dBv C22 0.1µ NR RECIN2 REC OUT1 –3dBv GND LINE OUT2 BIAS N R2 1.2k –26dBv NR TCH2 AMS SW R1 1.2k –4dBv NR TCL2 NR TCH1 NR OUT2 NR TCL1 S IN2 –7dBv REC IN2 NR OUT1 NR RECOUT2 –7dBv REC OUT2 PASS SW Audio SG –24dBv REC MUTE –7dBv CAL IN NR RECOUT1 MT C2 METER SW Amp 2.2dB –3dBv BS FB –26dBv AMS FB IREF AMS TC NR IREF AMS OUT MT C1 S SW BIAS M NR SW SPEED – 13 – BIAS C REC CAL Electrical Characteristics Measurement Circuit R62 1k R63 1k S39 S41 S53 S43 S45 R64 1k S38 GND GND S44 C48 100µ C49 100µ S46 S47 S48 AMS MODE AMS OFF DOLBY NR BS MODE MUTE METER ON PASS HIGH SPEED NORMAL SPEED METER MUTE PB REC PB A EQ FLAT CrO2 NORMAL PB A EQ 70µ PB IN A METAL PB IN B S55 S56 GND GND DOLBY B DOLBY OFF DOLBY C DOLBY S DOLBY B/C C51 3.3µ GND S40 MUTE OFF CALIBRATION C52 3.3µ GND GND L M H MUTE ON GND S50 GND S49 GND S57 S58 S51 S52 S54 R65 1k R66 1k R67 1k R68 1k R59 R61 56k 1k +1.1dBv R60 56k S32 S33 C50 10µ S34 S35 S36 S37 +1.1dBv R56 1k R57 1k R58 1k V2 2.5 V1 0.5 V3 4.2 A DC Ammeter 5V A DC Ammeter A GND Power Supply DC Ammeter Vcc VEE CXA1878Q GND ERASE HEAD REC/PB HEAD [DECK-B] REC/PB HEAD [DECK-B (R)] [DECK-B (L)] GND PB Only HEAD [DECK-A (L)] PB Only HEAD [DECK-A (R)] Bias OSC LINE IN L-ch R-ch C8 150p C2 75p GND C5 2.2µ C6 2.2µ C3 150p R5 12k C1 75p L1 27mH C4 2.2µ GND REC/PB PB Amp PB REC PB REC/PB REC PB Amp PB Amp PB Amp R6 12k L2 27mH C7 2.2µ R4 15k R3 15k GND R10 100k GND C13 3.3µ –3dBv GND –31dBv –31dBv –31dBv –31dBv C14 3.3µ –3dBv C10 R9 2.2µ 180k C9 2.2µ –10dBv –10dBv R11 100k GND C15 2.2µ C16 2.2µ MPX Filter R13 3.3k R42 50k R41 50k R14 3.3k MPX Filter R15 8.2k R17 2k C17 2.2µ 3 4 DOLBY S NR C21 0.068µ R19 10k 7 6 5 8 C25 0.47µ R21 4.7k R22 8.2k 9 R25 27k 10 R26 20k 11 C30 1.0µ 12 BIAS CONTROL 14 13 15 16 17 18 25 24 23 22 21 DECK A/B B EQ A EQ DVCC VCC 19 R31 56k R32 56k +1dBv +1dBv C35 3.3µ 26 METER1 MODE SW 20 27 28 29 30 31 32 METER2 REC VOL REC BAL DGND VEE GP CAL 33 34 35 36 37 38 39 40 R30 100k 41 C34 0.1µ 42 R29 1MEG C33 0.015µ 43 R28 10k C32 1.5µ 44 R27 1k C31 1.0µ 45 C26 2.2µ CAL OSC C29 2.2µ 46 C23 2.2µ C27 2.2µ R23 8.2k 47 C19 0.1µ C24 2.2µ 48 C22 0.068µ C28 0.47µ R24 4.7k 49 2 VOL OUT1 C20 0.1µ DOLBY S NR R20 10k 50 1 VOL IN1 63 64 NR PBIN1 PB OUT1 PB INB1 PB INA1 GND PB INA2 PB INB2 PB OUT2 NR PBIN2 VOL IN2 VOL OUT2 51 C18 2.2µ 62 61 60 59 58 57 56 55 54 53 52 R16 8.2k R18 2k NR RECIN2 C11 R12 4.7µ 100k –6dBv LINE OUT2 NR TCH1 GND R1 12k NR TCH2 NR TCL1 –6dBv NR TCL2 REC OUT1 L-ch NR OUT2 IREF LINE OUT S IN2 NR IREF –6dBv REC IN2 MT C1 C12 4.7µ NR RECOUT2 BIAS N R-ch REC OUT2 AMS SW R7 4.7k REC MUTE PASS SW R2 –6dBv 12k CAL IN METER SW R8 4.7k MT C2 NR RECIN1 BS FB LINE OUT1 AMS FB NR OUT1 AMS TC S IN1 AMS OUT REC IN1 S SW NR RECOUT1 NR SW BIAS M REC CAL BIAS C – 14 – SPEED C40 3.3µ C36 1µ C37 1µ C38 10µ C39 10µ GND C41 10µ C42 10µ R35 50k GND R33 50k GND R36 50k GND R34 50k GP CAL REC CAL REC CALIBRATION REC LEVEL & BALANSE Application Circuit R37 10k R38 10k HP Amp HP Amp REC MUTE S SW NR SW DECK A/B B-DECK EQ A-DECK EQ MODE (REC/PB) SPEED METER SW PASS SW AMS/BS VCC DVCC METER (L) METER (R) to AMS Control L : SIGNAL EXIST H : NO SIGNAL DVCC VEE HEADPHONES R39 220 R40 220 CXA1878Q to MICROCOMPUTER 7.3 2.9 7.1 11.3 3.9 NORM-tape, NORM-speed mode Input a 3kHz signal (–20dB level down) to the REC EQ IN pin and then measure the relative deviation from NORM-NS, 315Hz mode. NORM-tape, NORM-speed mode Input a 8kHz signal (–20dB level down) to the REC EQ IN pin and then measure the relative deviation from NORM-NS, 315Hz mode. NORM-tape, NORM-speed mode Input a 12kHz signal (–20dB level down) to the REC EQ IN pin and then measure the relative deviation from NORM-NS, 315Hz mode. CrO2-tape, NORM-speed mode Input a 3kHz signal (–20dB level down) to the REC EQ IN pin and then measure the relative deviation from NORM-NS, 315Hz mode. CrO2-tape, NORM-speed mode Input a 8kHz signal (–20dB level down) to the REC EQ IN pin and then measure the relative deviation from NORM-NS, 315Hz mode. CrO2-tape, NORM-speed mode Input a 12kHz signal (–20dB level down) to the REC EQ IN pin and then measure the relative deviation from NORM-NS, 315Hz mode. METAL-tape, NORM-speed mode Input a 3kHz signal (–20dB level down) to the REC EQ IN pin and then measure the relative deviation from NORM-NS, 315Hz mode. NORM-NORM mode Recording REC-EQ frequency response 1 equalizer amplifier (3kHz, –20dB) NORM-NORM mode Recording REC-EQ frequency response 2 equalizer amplifier (8kHz, –20dB) NORM-NORM mode Recording REC-EQ frequency response 3 equalizer amplifier (12kHz, –20dB) CrO2-NORM mode Recording REC-EQ frequency response 1 equalizer amplifier (3kHz, –20dB) CrO2-NORM mode Recording REC-EQ frequency response 2 equalizer amplifier (8kHz, –20dB) CrO2-NORM mode Recording REC-EQ frequency response 3 equalizer amplifier (12kHz, –20dB) METAL-NORM mode Recording REC-EQ frequency response 1 equalizer amplifier (3kHz, –20dB) 2.5 –1.9 –26 Input level when the reference output level is 315Hz, –3.0dBv (For measurement, input a 315Hz, –24.5dBv signal to the REC EQ IN pins (Pins 7 and 45) and then measure the output level.) Recording equalizer amplifier Recording Recording reference input level equalizer amplifier NORM-NORM mode — Recording equalizer amplifier reference output level (315Hz) (This output level is the tape reference 0dB which generates magnetic flux of 250nWb/m) All of the recording equalizer amplifier blocks use this level as their reference level. Recording equalizer amplifier Recording Recording reference output equalizer amplifier level NORM-NORM mode ±6.5 Operating voltage range (positive/negative dual power supplies) Entire LSI Min. 28 Conditions Current consumption (ICC) Item – 15 – 5.4 14.3 9.1 4.4 10.3 4.5 –0.4 –24.5 –3.0 ±7.0 38 Typ. 6.9 17.3 11.1 5.9 13.3 6.5 1.0 –23 — ±8.0 48 Max. dB dB dB dB dB dB dB dBv dBv V mA Unit (Ta = 25°C, VCC = 7.0V, VEE = –7.0V) Entire LSI Block Electrical Characteristics CXA1878Q CrO2-tape, HIGH-speed mode Input a 15kHz signal (–20dB level down) to the REC EQ IN pin and then measure the relative deviation from NORM-NS, 315Hz mode. CrO2-tape, HIGH-speed mode Input a 20kHz signal (–20dB level down) to the REC EQ IN pin and then measure the relative deviation from NORM-NS, 315Hz mode. METAL-tape, HIGH-speed mode Input a 5kHz signal (–20dB level down) to the REC EQ IN pin and then measure the relative deviation from NORM-NS, 315Hz mode. METAL-tape, HIGH-speed mode Input a 15kHz signal (–20dB level down) to the REC EQ IN pin and then measure the relative deviation from NORM-NS, 315Hz mode. METAL-tape, HIGH-speed mode Input a 20kHz signal (–20dB level down) to the REC EQ IN pin and then measure the relative deviation from NORM-NS, 315Hz mode. CrO2-HIGH mode Recording REC-EQ frequency response 3 equalizer amplifier (20kHz, –20dB) METAL-HIGH mode Recording REC-EQ frequency response 1 equalizer amplifier (5kHz, –20dB) METAL-HIGH mode Recording REC-EQ frequency response 2 equalizer amplifier (15kHz, –20dB) METAL-HIGH mode Recording REC-EQ frequency response 3 equalizer amplifier (20kHz, –20dB) NORM-tape, HIGH-speed mode Input a 20kHz signal (–20dB level down) to the REC EQ IN pin and then measure the relative deviation from NORM-NS, 315Hz mode. NORM-HIGH mode Recording REC-EQ frequency response 3 equalizer amplifier (20kHz, –20dB) CrO2-HIGH mode Recording REC-EQ frequency response 2 equalizer amplifier (15kHz, –20dB) NORM-tape, HIGH-speed mode Input a 15kHz signal (–20dB level down) to the REC EQ IN pin and then measure the relative deviation from NORM-NS, 315Hz mode. NORM-HIGH mode Recording REC-EQ frequency response 2 equalizer amplifier (15kHz, –20dB) CrO2-tape, HIGH-speed mode Input a 5kHz signal (–20dB level down) to the REC EQ IN pin and then measure the relative deviation from NORM-NS, 315Hz mode. NORM-tape, HIGH-speed mode Input a 5kHz signal (–20dB level down) to the REC EQ IN pin and then measure the relative deviation from NORM-NS, 315Hz mode. NORM-HIGH mode Recording REC-EQ frequency response 1 equalizer amplifier (5kHz, –20dB) CrO2-HIGH mode Recording REC-EQ frequency response 1 equalizer amplifier (5kHz, –20dB) METAL-tape, NORM-speed mode Input a 12kHz signal (–20dB level down) to the REC EQ IN pin and then measure the relative deviation from NORM-NS, 315Hz mode. METAL-NORM mode Recording REC-EQ frequency response 3 equalizer amplifier (12kHz, –20dB) Conditions METAL-tape, NORM-speed mode Input a 8kHz signal (–20dB level down) to the REC EQ IN pin and then measure the relative deviation from NORM-NS, 315Hz mode. Item METAL-NORM mode Recording REC-EQ frequency response 2 equalizer amplifier (8kHz, –20dB) Block – 16 – 11.8 9.5 5.9 11.4 8.6 3.9 7.4 4.0 –1.3 10.4 7.1 Min. 15.3 12.0 7.4 14.9 11.1 5.4 10.9 6.5 0.2 13.4 9.1 Typ. 18.8 14.5 8.9 18.4 13.6 6.9 14.4 9.0 1.7 16.4 11.1 Max. dB dB dB dB dB dB dB dB dB dB dB Unit CXA1878Q Item NORM-tape, NORM-speed mode, RL = 2.7kΩ Input a 1kHz signal and set the output level so that THD (total harmonic distortion) is 1%. (Measure the distortion of a +11dB level-up signal.) Conditions NORM-tape, NORM-speed mode With no signal, measure the DC offset voltage of the REC OUT pin. NORM-NORM mode Recording Output DC offset voltage equalizer amplifier (REC OUT pin) – 17 – –7.5 2.7 –4.8 8.0 NORM-tape, NORM-speed mode, REC-CAL = 0.0V NORM-NORM mode Recording REC-EQ REC-CAL characteristics 2 Input a 315Hz signal (–20dB level down) and measure the amount of change equalizer amplifier compared to when the REC-CAL function is at the standard setting. (REC-CAL = 0.0V) NORM-tape, NORM-speed mode, Gp-CAL = 5.0V NORM-NORM mode Recording REC-EQ Gp-CAL characteristics 1 Input a 8kHz signal (–20dB level down) and measure the amount of change equalizer amplifier compared to when the Gp-CAL function is at the standard setting. (Gp-CAL = 5.0V) NORM-tape, NORM-speed mode, Gp-CAL = 0.0V NORM-NORM mode Recording REC-EQ Gp-CAL characteristics 2 Input a 8kHz signal (–20dB level down) and measure the amount of change equalizer amplifier compared to when the Gp-CAL function is at the standard setting. (Gp-CAL = 0.0V) REC-VOL = 5.0V, REC-BAL = 2.5V Recording volume amplifier Recording volume Recording volume characteristics 1 Input a 1kHz, –10dBv signal to the VOL IN pin and measure the full (REC-VOL = 5.0V, REC-BAL = 2.5V) gain of the recording volume amplifier. 9.0 –3.3 4.2 –6.0 6.3 4.8 NORM-tape, NORM-speed mode, REC-CAL = 5.0V NORM-NORM mode Recording REC-EQ REC-CAL characteristics 1 Input a 315Hz signal (–20dB level down) and measure the amount of change equalizer amplifier compared to when the REC-CAL function is at the standard setting. (REC-CAL = 5.0V) –99.9 10.0 65.0 0.14 12.4 Typ. –6.6 — –500 57.0 — 11.0 Min. NORM-tape, NORM-speed mode, REC-MUTE = 2.5V NORM-NORM mode Recording REC-EQ mute characteristics 2 Input a 1kHz, 0dB (reference level) signal and measure the attenuation –8.1 equalizer amplifier characteristics curve of the soft mute function (when REC-MUTE = 2.5V). (REC-MUTE = 2.5V) NORM-tape, NORM-speed mode, REC-MUTE = 0.5V NORM-NORM mode Recording REC-EQ mute characteristics 1 Input a 1kHz signal (+12dB level up) and measure the attenuation equalizer amplifier when REC MUTE is ON. (Use a 1kHz BPF.) (REC-MUTE = 0.5V) NORM-tape, NORM-speed mode, Rg = 5.1kΩ With no signal, measure the noise using the “A”-WGT filter. (The measured value is indicated as the relative value compared to the reference level.) NORM-NORM mode Recording REC-EQ S/N ratio equalizer amplifier (“A”-WGT filter) NORM-tape, NORM-speed mode, RL = 2.7kΩ NORM-NORM mode Recording REC-EQ total harmonic distortion Input a 1kHz, 0dB (reference input level) signal and measure the distortion. equalizer amplifier (Measure the distortion as THD + N.) (1kHz, 0.0dB, RL = 2.7kΩ) NORM-NORM mode Recording REC-EQ signal handling equalizer amplifier (1kHz, THD = 1%, RL = 2.7kΩ) Block 10.0 –1.8 5.7 –4.5 7.8 –5.1 –80 500 — 0.6 — Max. dB dB dB dB dB dB dB mV dB % dB Unit CXA1878Q – 18 – — 6.0 6.0 12.0 REC-VOL = 5.0V, REC-BAL = 5.0V, (1kHz BPF) Recording volume amplifier Recording volume REC-VOL balance characteristics 2 Input a 1kHz, +2dBv signal and measure the attenuation of VOL OUT 2. (REC-VOL = 5.0V, REC-BAL = 5.0V) (Input a –10dBv signal and confirm that there is no attenuation at VOL OUT 1.) Line amplifier NR mode NR mode gain Input a 1kHz, –11dBv signal to the NR PB IN pin and measure the gain. (NR PB IN = 1kHz, –11.0dBv) Line amplifier PASS mode PASS mode gain Input a 1kHz, –11dBv signal to the NR PB IN pin and measure the gain. (NR PB IN = 1kHz, –11.0dBv) PASS mode, RL = 2.7kΩ Line amplifier Input a 1kHz signal and set the output level so that the THD is 1%. Signal handling (1kHz, THD = 1%, RL = 2.7kΩ) (Measure the distortion when the output is +1dBv.) Line amplifier Line amplifier Line amplifier –150 — REC-VOL = 5.0V, REC-BAL = 2.5V With no signal, measure the DC offset voltage of the VOL OUT pin. REC-VOL = 5.0V, REC-BAL = 0.0V, (1kHz BPF) Recording volume amplifier Recording volume REC-VOL balance characteristics 1 Input a 1kHz, +2dBv signal and measure the attenuation of VOL OUT 1. (REC-VOL = 5.0V, REC-BAL = 0.0V) (Input a –10dBv signal and confirm that there is no attenuation at VOL OUT 2.) Recording volume amplifier Recording volume Output DC offset voltage (VOL OUT pin) 80 — REC-VOL = 2.0V, REC-BAL = 2.5V, RL = 2.7kΩ Recording volume amplifier Recording volume REC-VOL total harmonic distortion Input a 1kHz, –10dBv signal (reference input level) and measure the distortion. (Measure the distortion as THD + N.) (1kHz, –6.0dBv, RL = 2.7kΩ) REC-VOL = 5.0V, REC-BAL = 2.5V With no signal, measure the noise using an “A”-WGT filter. (The measured value is indicated as the relative value compared to the full-gain level.) 2.0 REC-VOL = 2.0V, REC-BAL = 2.5V, RL = 2.7kΩ Recording volume amplifier Input a 1kHz signal and set the input level so that the THD is 1%. Recording volume REC-VOL signal handling (1kHz, THD = 1%, RL = 2.7kΩ) (Measure the distortion when the output is +2dBv.) Recording volume amplifier Recording volume REC-VOL S/N ratio (“A”-WGT filter) — Min. REC-VOL = 0.0V, REC-BAL = 2.5V Recording volume amplifier Recording volume Recording volume attenuation Input a 1kHz, +2dBv signal and measure the maximum volume (REC-VOL = 0.0V, REC-BAL = 2.5V) attenuation of the recording volume amplifier. (Use a 1kHz BPF.) Conditions –9.4 Item REC-VOL = 2.0V, REC-BAL = 2.5V Recording volume amplifier Recording volume Recording volume characteristics 2 Input a 1kHz, –10dBv signal to the VOL IN pin and measure the (REC-VOL = 2.0V, REC-BAL = 2.5V) attenuation of the recording volume amplifier. Block 15.5 7.0 7.0 –93.2 –93.2 4.2 97.5 0.09 3.41 –104.7 –8.4 Typ. — 8.0 8.0 –60 –60 150 — 0.5 — –80 –7.4 Max. dB dB dB dB dB mV dB % dBv dB dB Unit CXA1878Q Conditions — 1.34 MUTE mode Input a 1kHz, +1dBv signal to the NR PB IN pin and measure the attenuation when LINE MUTE is on. (Use a 1kHz BPF.) METER ON, CAL OFF, PB Input a 1kHz, –11dBv signal to the NR PB IN pin and measure the output DC voltage at the METER pin. Line amplifier MUTE mode characteristics (1kHz BPF) Level meter amplifier Level meter characteristics 1 (PASS IN = 1kHz, –11dBv) Line amplifier Level meter – 19 – — METER MUTE ON, PB Level meter amplifier Level meter MUTE characteristics Input a 1kHz, +1dBv (12dB level up) signal to the NR PB IN pin and measure the output DC voltage at the METER pin. (PASS IN = 1kHz, +1.0dBv) Level meter 3.0 1.6 0.5 1.64 –111 0 84.1 0.07 Typ. –1.0 –5.7 DECK-A, A-EQ = 120µs, NORM-speed mode Input a 5kHz, –31dBv (reference input level) signal and then measure the relative deviation from the 120µs-NS, 315Hz mode. DECK-A, A-EQ = 70µs, NORM-speed mode Input a 5kHz, –31dBv (reference input level) signal and then measure the relative deviation from the 120µs-NS, 315Hz mode. Playback equalizer amplifier Playback PB-EQ frequency response 1 equalizer amplifier 120µs-NS, DECK-A mode Playback equalizer amplifier Playback PB-EQ frequency response 2 equalizer amplifier 70µs-NS, DECK-A mode –4.2 0.0 –11.9 –10.9 1.3 METER ON, CAL ON, REC Level meter amplifier Level meter CAL characteristics Input a 1kHz, –28dBv (–17dB level down) signal to the NR PB IN pin and measure the output DC voltage at the METER pin. (PASS IN = 1kHz, –28dBv) Level meter DECK-A, A-EQ = 120µs, NORM-speed mode 120µs, DECK-A mode Playback Playback reference output level Input a 315Hz, –31dBv (reference input level) signal to the PB IN pin equalizer amplifier (Playback equalizer amplifier gain) and measure the output level. 0.2 METER ON, CAL OFF, PB Input a 1kHz, –21dBv (–10dB level down) signal to the NR PB IN pin and measure the output DC voltage at the METER pin. Level meter amplifier Level meter characteristics 2 (PASS IN = 1kHz, –21dBv) Level meter –200 PASS mode With no signal, measure the DC offset voltage of the LINE OUT pin. Line amplifier Output DC offset voltage (LINE OUT pin) Line amplifier 80 PASS mode, Rg = 5.1kΩ With no signal, measure the noise using the “A”-WGT filter. (The measured value is indicated as the relative value compared to the reference level. — Min. Line amplifier Line amplifier S/N ratio (“A”-WGT filter) PASS mode, RL = 2.7kΩ Line amplifier Line amplifier total harmonic distortion Input a 1kHz, –11dBv signal (reference input level) and measure the (1kHz, –11.0dBv, RL = 2.7kΩ) distortion. (Measure the distortion as THD + N.) Item Line amplifier Line amplifier Block –2.7 1.0 –9.9 50.0 1.9 0.8 1.94 –80 200 — 1.0 Max. dB dB dBv mV V V V dB mV dB % Unit CXA1878Q – 20 – 1.0 AMS/BS amplifier 0.88 AMS OFF mode Input a 5kHz, –11dBv signal to the NR PB IN pin and measure the current flowing to the AMS OUT pin. AMS/BS amplifier AMS output leak current (AMS OUT pin) AMS/BS amplifier — –35.5 –30.5 –25.5 BS mode, fin = 5kHz, reference level –11dBv Input level when the AMS OUT pin level changes from high to low. Input the signal to the NR PB IN pin and measure the level at the AMS OUT pin. AMS/BS amplifier BS signal detection level BS mode –5.0 –15.0 –10.0 1.0 AMS/BS amplifier 0.0 200 — 0.5 — –7.1 –3.8 Max. AMS mode, fin = 5kHz, reference level –11dBv Input level when the AMS OUT pin level changes from high to low. Input the signal to the NR PB IN pin and measure the level at the AMS OUT pin. –1.0 DECK-B, B-EQ = NORM-tape, NORM-speed mode Input a 1kHz, –31dBv (reference input level) signal to the DECK-B side and then measure the relative deviation from the DECK-A, 120µs-NS, 315Hz mode. Recording equalizer amplifier DECK-A/B switching Playback equalizer amplifier characteristics 120µs-NS, DECK-B mode –5 75.6 0.03 22 –8.6 –5.3 Typ. AMS/BS amplifier AMS signal detection level AMS mode –200 70 DECK-A, A-EQ = 120µs, NORM-speed mode With no signal, measure the DC offset voltage of the PB OUT pin. DECK-A, A-EQ = 120µs, NORM-speed mode, Rg = 5.1kΩ With no signal, measure the noise using the “A”-WGT filter. (The measured value is indicated as the relative value compared to the reference level.) 120µs-NS, DECK-A mode Playback Output DC offset voltage equalizer amplifier (PB OUT pin) 120µs-NS, DECK-A mode Playback PB-EQ S/N ratio equalizer amplifier (“A”-WGT filter) — DECK-A, A-EQ = 120µs, NORM-speed mode, RL = 2.7kΩ 120µs-NS, DECK-A mode Playback PB-EQ total harmonic distortion Input a 1kHz, –31dBv (reference input level) signal and measure the equalizer amplifier distortion. (Measure the distortion as THD + N.) (1kHz, 0.0dB, RL = 2.7kΩ) –10.1 DECK-A, A-EQ = 70µs, HIGH-speed mode Input a 5kHz, –31dBv (reference input level) signal and then measure the relative deviation from the 120µs-NS, 315Hz mode. Playback equalizer amplifier Playback PB-EQ frequency response 4 equalizer amplifier 70µs-HS, DECK-A mode 12 –6.8 DECK-A, A-EQ = 120µs, HIGH-speed mode Input a 5kHz, –31dBv (reference input level) signal and then measure the relative deviation from the 120µs-NS, 315Hz mode. Playback equalizer amplifier Playback PB-EQ frequency response 3 equalizer amplifier 120µs-HS, DECK-A mode DECK-A, A-EQ = 120µs, NORM-speed mode, RL = 2.7kΩ 120µs-NS, DECK-A mode Playback Input a 1kHz signal and set the output level so that the THD is 1%. PB-EQ signal handling equalizer amplifier (1kHz, THD = 1%, RL = 2.7kΩ) (Measure the distortion of a +12dB level-up signal.) Min. Item Conditions Block µA dB dB dB mV dB % dB dB dB Unit CXA1878Q Min. –11 1.4 3.9 9.7 –1.1 PB mode, NR OFF, f = 1kHz Input a signal to the NR PB IN pin and measure the level at which the level of the DOLBY OUT pin reaches –6dBm. REC, Dolby B type mode Input a 500Hz, –25dB signal from the REC IN pin and measure the boost at the REC OUT pin. REC, Dolby B type mode Input a 5kHz, –25dB signal from the REC IN pin and measure the boost at the REC OUT pin. REC, Dolby B type mode Input a 10kHz, –40dB signal from the REC IN pin and measure the boost at the REC OUT pin. REC, Dolby B type mode Input a 10kHz, 0dB signal from the REC IN pin and measure the boost at the REC OUT pin. PB mode PB IN level B type encoding Boost characteristics 1 B type encoding Boost characteristics 2 B type encoding Boost characteristics 3 B type encoding Boost characteristics 4 DOLBY DOLBY DOLBY DOLBY DOLBY –26 REC mode, NR OFF, f = 1kHz Input a signal to the REC IN pin and measure the level at which the level of the DOLBY OUT pin reaches –6dBm. REC mode REC IN level DOLBY –26 — REC mode, NR OFF 1kHz, assume Dolby level of –6dBm as 0dB. Dolby level DOLBY REC mode, NR OFF, f = 1kHz Input a signal to the CAL IN pin and measure the level at which the level of the DOLBY OUT pin reaches –6dBm. — Input a 2mA signal to the BIAS M pin and measure the DC output voltage at the BIAS M pin. BIAS M output voltage (METAL mode) BIAS SW REC mode CAL IN level — Input a 2mA signal to the BIAS C pin and measure the DC output voltage at the BIAS C pin. BIAS C output voltage (CrO2 mode) BIAS SW DOLBY — Input a 2mA signal to the BIAS N pin and measure the DC output voltage at the BIAS N pin. BIAS N output voltage (NORMAL mode) — Conditions AMS mode AMS/BS amplifier AMS output saturation voltage Input a 5kHz, –11dBv signal to the NR PB IN pin and measure the output voltage when a 1mA current flows to the AMS OUT pin. (AMS OUT pin) Item BIAS SW AMS/BS amplifier Block – 21 – 0.4 10.4 5.4 2.9 –10 –25 –25 –6.0 0.4 0.4 0.4 0.17 Typ. 1.9 11.4 6.9 4.4 –9 –24 –24 — 0.6 0.6 0.6 1.0 Max. dB dB dB dB dBm dBm dBm dBm V V V V Unit CXA1878Q –1.5 13.5 — — — PB, Dolby C type mode Input a 20kHz, –10dBm signal from the NR PB IN pin and measure the relative deviation from the REC OUT output NR OFF mode. REC, NR OFF mode Input a 1kHz signal and set the output level so that the THD is 1%. (Measure the distortion using a +13.5dB level-up signal from the reference.) REC, NR OFF mode Input a 1kHz, +10dB signal from the REC IN pin and measure the distortion. (Measure the distortion as THD + N.) REC, Dolby B type mode Input a 1kHz, +10dB signal from the REC IN pin and measure the distortion. (Measure the distortion as THD + N.) REC, Dolby C type mode Input a 1kHz, +10dB signal from the REC IN pin and measure the distortion. (Measure the distortion as THD + N.) PB mode Frequency response REC mode Signal handling NR OFF total harmonic distortion Dolby B type total harmonic distortion Dolby C type total harmonic distortion DOLBY DOLBY DOLBY DOLBY DOLBY 3.5 REC, Dolby C type mode Input a 5kHz, –25dB signal from the REC IN pin and measure the boost at the REC OUT pin. C type encoding Boost characteristics 5 DOLBY –5.5 5.4 REC, Dolby C type mode Input a 2kHz, –25dB signal from the REC IN pin and measure the boost at the REC OUT pin. C type encoding Boost characteristics 4 DOLBY REC, Dolby C type mode Input a 10kHz, 0dB signal from the REC IN pin and measure the boost at the REC OUT pin. 18.7 REC, Dolby C type mode Input a 2kHz, –60dB signal from the REC IN pin and measure the boost at the REC OUT pin. C type encoding Boost characteristics 3 DOLBY C type encoding Boost characteristics 6 7.2 REC, Dolby C type mode Input a 500Hz, –25dB signal from the REC IN pin and measure the boost at the REC OUT pin. C type encoding Boost characteristics 2 DOLBY DOLBY 14.2 Min. REC, Dolby C type mode Input a 500Hz, –60dB signal from the REC IN pin and measure the boost at the REC OUT pin. Conditions C type encoding Boost characteristics 1 Item DOLBY Block – 22 – 0.09 0.06 0.04 15.4 0 –3.5 5.5 7.4 20.7 9.2 16.2 Typ. 0.5 0.5 0.5 — 1.5 –1.5 7.5 9.4 22.7 11.2 18.2 Max. % % % dB dB dB dB dB dB dB dB Unit CXA1878Q – 23 – Control circuit Control circuit Control circuit Control circuit 0.0 NR SW, S SW, DECK A/B, EQ, B EQ, and PASS SW pin voltages AMS SW, MODE SW, SPEED, and METER SW pin voltages AMS SW, MODE SW, SPEED, and METER SW pin voltages Mode control Control circuit low level Mode control Control circuit high level Mode control Control circuit low level 0.0 3.5 2.2 Mode control NR SW, S SW, DECK A/B, EQ, B EQ, and PASS SW pin voltages Control circuit medium level 4.2 REC mode, NR OFF → C type With no signal, measure the deviation in the output DC offset voltage at –100 the REC OUT pin when switching from NR OFF mode to C type mode. REC mode Output DC offset voltage (REC OUT pin) DOLBY NR SW, S SW, DECK A/B, EQ, B EQ, and PASS SW pin voltages — REC, NR OFF mode Input a 1kHz, +10dB signal from the NR PB IN pin and measure the PB → REC crosstalk. (Use a 1kHz BPF.) REC mode Playback → recording crosstalk DOLBY Mode control Control circuit high level — PB, NR OFF mode Input a 1kHz, +10dB signal from the REC IN pin and measure the REC → PB crosstalk. (Use a 1kHz BPF.) PB mode Recording → playback crosstalk DOLBY Control circuit 60.0 Min. Conditions DOLBY Item REC, Dolby C type mode, Rg = 5.1kΩ With no signal, measure the noise using the CCIR/ARM filter. (The measured value is indicated as the relative value compared to the DOLBY OUT level.) Binary swithing Ternary switching REC mode Dolby C type S/N ratio Block — — — — — 0.0 –113 –77.5 61.0 Typ. 0.5 VCC 0.5 2.8 VCC 100 –70 –70 — Max. V V V V V mV dB dB dB Unit CXA1878Q GND 10k to Control IC GND R1 50k DVcc for R-ch R-ch GND [DECK-A] VEE GND C2 2.2µ R5 20k R6 27k 2.2µ PB Amp C1 PB Only HEAD – 24 – DVCC VEE GND VEE Vcc R2 50k C3 R7 2.2µ 50k R3 GND 180k GND GND R4 15k ∗ Sourse Impedance 10kΩ L-ch LINE IN –6dBv 600 –11dBv R11 18k PRE VGS (C) R10 2k D1 B DECK VGS (C) –31dBv R8 50k PB INB –31dBv PB INA A DECK R9 50k VGS (C) NR IREF DGND DVcc IREF (REC/PB) GND (VG) VEE Vcc S SW (S/BC/CAL) AMS SW (OFF/AMS/BS) NR SW (OFF/B/C) MODE SW (REC/PB) METER SW (ON/MUTE) REC BAL PASS SW (NR/MUTE/PASS) REC VOL REC MUTE DECK A/B (A/B) R12 6.5k –10dBv ×1 SPEED (NS/HS) B EQ (N/C/M) A EQ (120/70) –10dBv VOL IN to LINE IN Gmb C4 200p –11dBv BIAS GND (A) PEA R14 30k RVA R13 6.5k CONTROL VGS VGS (C) (B) Gm1 R15 3.3k –14dBv R17 40k R18 6.2k C5 2.2µ PB OUT –11dBv (–30dBm) –31dBv R16 36k NRPB IN (–10dBm) –11dBv ×1 R26 12k R24 22.5k VGS (C) R25 1.5k R29 100k VEE –26dBv BS FB GND C11 1.5µ C9 0.015µ GND R33 1k BS –15dBv R30 10k AMS FB AMS/BS AMS PASS COMP METER OFF R46 2k R47 12k R44 3.3k for R-ch R-ch R50 4.7k C16 4.7µ –4dBv GND (A) HP Amp R55 220 ×1 Gm5 GND for R-ch DGND REA B EQ MTR C21 3.3µ METER GND R67 50k GND 47k GND –6dBv VM to AMS Control ∗ Load Impedance 47kΩ from LINE OUT R64 100k DVcc BIAS CONTROL R65 50k DVcc PB PB Amp REC [DECK-B] REC/PB HEAD Bias OSC L1 27mH C24 75p REC/PB GND C23 150p C22 R66 3.3µ 12k to METER IC AMS OUT VEE R62 150 +1.1dBv (1.6V) Q BIAS-M VEE BIAS-C VEE Q Q BIAS-N GP CAL REC CAL R63 50k –3dBv REC OUT GND GND R61 56k R60 10k Vcc HEADPHONES R58 36k R59 10k VGS (C) +6dBv VGS (B) CALIBRATION GND Gm4 (A) C20 100p C19 100p Gm3 C18 1.0µ R57 40k R56 24k MT C GND R54 14k R49 10k GND GND R48 GND 100k –6dBv R45 12k LINE OUT L-ch LINE OUT C15 0.1µ R42 2.9k MUTE NR NR/PASS /MUTE ×1 R53 8k ×1 C17 200p –7dBv GND (A) GND –6dBv R51 20k R52 20k (–6dBm) –7dBv OFF METER DGND Q VGS R39 5k (C) VGS (B) DGND DVcc DVcc ON OFF VGS (C) Gm2 VGS (C) BPF –6dBv –7dBv NR/PASS/MUTE VGS NR LINE (C) PASS –4dBv MUTE AMS TC DET –11dBv R40 15k R43 2.5k –0.5dBv R41 20k METER ON ON CAL VGS (B) ON CAL OFF –7dBv (–6dBm) –7dBv C14 2.2µ GND GND REC IN REC VGS (C) –24dBv R38 50k R37 10k C13 0.47µ NR RECOUT R34 8.2k –7dBv (–6dBm) R36 1MEG S SW –15dBv AMS R32 100k C12 2.2µ BC/S/CAL VGS (C) ×1 CAL S-NR B/C-NR R31 40k S IN (–6dBm) R35 4.7k Fig. 1. Functional block diagram C8 0.068µ NR TCL VEE NR TCH R28 12.5k LLS VF ANTS (–6dBm) NR OUT DOLBY S NR –15dBv VGS C10 (B) SUM 106p R23 40k R27 40k for R-ch HLS VF Dolby B/C-NR R22 1.5k PB MOA REC & CAL R23 PB REC REC/PB OFF VEE SSK C7 0.1µ ON VGS (C) CAL IN –26dBv R21 10k C8 VGS (C) –11dBv R19 4k for R-ch NR RECIN C6 2.2µ R20 2k VGS (C) –26dBv (–25dBm) VGS (C) –10dBv VOL OUT MPX Filter GND METAL CrO2 NORM OSC CXA1878Q Description of Operation The CXA1878Q is a Dolby B-C type NR system with a built-in recording/playback equalizer amplifier, electronic volume, AMS, BIAS SW, and meter circuit. In addition, this chip also contains an S type (CXA1417S/Q) select switch, enabling the construction of a 2-channel Dolby B-C-S type NR system by using the CXA1878Q together with two CXA1417S/Q encoder units. The CXA1878Q has the circuit configuration shown in Fig. 1. CXA1878Q 1. Reference levels (1) Recording equalizer amplifier output level (315Hz, –3dBv) [∗ when the recording equalizer amplifier input level is –24dBv] (2) Playback equalizer amplifier output level (315Hz, –11dBv) [∗ when the playback equalizer amplifier input level is –31dBv] (3) Dolby The Dolby level is measured at the recording output pin (REC OUT) at –6dBm (388mVrms) in the NR OFF mode. Reference levels for the recording input pin (LINE IN), playback input pin (PB IN) and line output pin (LINE OUT) are defined as the levels which apply the Dolby level to REC OUT in the NR OFF mode. 2. System control methods (1) Mode settings table Pin No. Pin voltage Symbol Low Remarks Medium High DOLBY NR ON C type 3-state CALIBRATION 3-state 34 NR SW 35 NR S SW DOLBY S DOLBY NR ON B type DOLBY B-C∗ 16 AMS SW AMS OFF AMS MODE BS MODE 3-state 20 MODE SW PB — REC 2-state 19 SPEED NORMAL SPEED — HIGH SPEED 2-state 25 DECK A/B PB IN A — PB IN B 2-state 23 A EQ PB IN A EQ FLAT — PB IN A EQ 70µ 2-state PB IN B EQ FLAT PB IN B EQ 70µ PB IN B EQ 70µ REC EQ NORMAL REC EQ CrO2 REC EQ METAL BIAS SW NORMAL BIAS SW CrO2 BIAS SW METAL 24 B EQ DOLBY NR OFF 3-state 17 PASS SW DOLBY NR MUTE PASS 3-state 18 METER SW METER ON — METER OFF 2-state Note: When 3-state input pins are open, the pin voltage is medium. ∗ The NR SW (Pin 34) operates only when the NR S SW (Pin 35) is set to medium. (2) Mode setting pin control voltage 3-state 2-state Control voltage Min. Max. High level 4.2 VCC Medium level 2.2 2.8 Low level 0.0 0.5 High level 3.5 VCC Low level 0.0 0.5 – 25 – CXA1878Q 3. Recording mute function The CXA1878Q recording mute function is implemented by using a built-in recording mute circuit which varies the recording equalizer amplifier gain according to the magnitude of the DC voltage applied to the REC MUTE pin just like an electronic volume control. Also, any desired soft mute or fader can be freely set depending on momentary changes in the DC voltage applied to the REC MUTE pin. Fig. 2 illustrates the recording mute waveforms. Fig. 2. Recording mute waveform REC MUTE control voltage Pin No. Symbol Pin voltage (V) 0.0 0.5 2.5 4.5 5.0 Remarks Decrease <<<< Increase 42 REC MUTE Less than –90 –90 — — — RECOUT attenuation (dB) NORM Tape, Norm-Speed, f = 1kHz 4. Recording level calibration The CXA1878Q allows the recording level to be finely adjusted with a DC voltage. Therefore, the recording level can be varied by approximately ±6dB simply by applying DC voltages of 0 to 5V (for dual power supply) to the REC CAL pin (Pin 33). The table below shows the input range of control voltages with the power supplies used.∗1 Output level Down (Vdown) REC CAL pin voltage DGND to 2.5V Typ. 2.5V∗2 Up (Vup) 2.5V to VCC ∗1 Although the above range of voltages can be input to the control pin, the controllable input voltage range is as follows. 2.5V < Vup ≤ 5.0V DGND ≤ Vdown < 2.5V ∗2 Control voltages for this IC are referenced to the DGND pin (Pin 30). Also note that when not using this recording level calibration function, simply leave the REC CAL pin (Pin 33) open, so that the voltage of the REC CAL pin is matched to the internal reference voltage (2.5V), with the recording level set for the standard gain. – 26 – CXA1878Q 5. High frequency calibration The CXA1878Q allows the high frequency response of the recording equalizer to be finely adjusted with a DC voltage. Therefore, the recording level in high frequencies (peak) can be varied by approximately ±4dB simply by applying DC voltages of 0 to 5V (for dual power supply) to the GP CAL pin (Pin 32). The table below shows the input range of control voltages with the power supplies used.∗3 Output level Down (Vdown) GP CAL pin voltage DGND to 2.5V Typ. 2.5V∗4 Up (Vup) 2.5V to VCC ∗3 Although the above range of voltages can be input to the control pin, the controllable input voltage range is as follows. 2.5V < Vup ≤ 5.0V DGND ≤ Vdown < 2.5V ∗4 Control voltages for this IC are referenced to the DGND pin (Pin 30). Also note that when not using this high frequency calibration function, simply leave the GP CAL pin (Pin 32) open, so that the voltage of the GP CAL pin is matched to the internal reference voltage (2.5V), with the high frequency equalizer amplifier characteristics set for the standard gain. Gain [dB] GP CAL REC CAL GP CAL REC CAL GP CAL REC CAL REC CAL REC CAL REC CAL Frequency [Hz] Fig. 3. Conceptual diagram of the recording level/high frequency calibration functions 6. Meter circuit The CXA1878Q has a built-in full-wave rectifier circuit for the level meter. Therefore, a DC voltage can be obtained by attaching time constants to the METER 1 and 2 output pins. The output voltage is set to 1.6V (+1.1dBv) during reference input. (for an external time constant of 56kΩ, 33µF) The MT C pin detects only the AC component. The low frequency cut-off is determined with the capacitor connected to this pin and the 14kΩ internal resistor. (Approximately 10Hz for 1µF) 7. Recording volume control circuit The CXA1878Q adjusts the size of the recording signal with a built-in control circuit. Therefore, the gain can be controlled by applying the voltage between DVCC and DGND to the REC VOL pin (Pin 28). (A 0dB signal is output when voltage of 2.0V is applied.) – 27 – CXA1878Q 8. Recording volume balance circuit The CXA1878Q contains a circuit which controls the balance between channels 1 and 2 of the recording volume. Therefore, the balance between channels 1 and 2 can be controlled by applying the voltage between DVCC and DGND to the REC BAL pin (Pin 29). (Signals which are not attenuated by the balance circuit are output from both channels when this control pin is open or when a voltage of DVCC/2 is applied.) REC VOL Control Voltage Pin No. Symbol Pin voltage (V) 0.0 0.5 2.0 4.5 5.0 Decrease <<<< Increase 28 REC VOL Less than –96 –96 0.0 — 9.0 4.5 5.0 Remarks VOLOUT1 and 2 attenuation (dB) BALANCE = 2.5V, f = 1kHz BALANC control voltage Pin No. Symbol Pin voltage (V) 0.0 0.5 2.5 Remarks Increase >>>> Decrease 0.0 29 REC BAL 0.0 0.0 –93 VOLOUT2 attenuation (dB) Less REC VOL = 5V, f = 1kHz than –93 Decrease <<<< Increase Less than –93 –93 0.0 0.0 0.0 VOLOUT1 attenuation (dB) REC VOL = 5V, f = 1kHz 9. Bias OSC power supply control circuit The CXA1878Q contains a switch circuit that selects the supply voltage for the bias oscillator. The supply voltage can be controlled with the B EQ pin (Pin 24). The maximum output current is 2mA. – 28 – CXA1878Q 10. AMS circuit The CXA1878Q has the music sensor circuit. DVCC R3 AMS TC C3 37 1kΩ NR PBIN1 62 NR PBIN2 54 36 AMS OUT COMP 0dB OP AMP WINDOW COMP 0dB 16kHz LPF 100kΩ G1 R1 [∗2] G2 R2 [∗1] [∗1] C1 C2 [∗2] Fig. 4. AMS circuit block diagram (1) AMS ON operation The signal input from PB NR IN first passes through the LPF, then through the HPF/sensitivity setting amplifier, and then through the WINDOW comparator where it is formed into a pulse wave. (See Fig. 5) This signal which has been formed into a pulse wave is integrated by a capacitor connected to the AMS TC pin (Pin 37) and then input to the comparator. (See Fig. 6) AMS OUT turns ON when the AMS TC pin voltage falls below the comparator threshold value. (When the sensitivity changes, the pulse width also changes.) WINDOW COMP detection level (sensitivity) The broken line shows the case detection level has changed. Fig. 5. Conceptual diagram of WINDOW comparator operation AMS TC pin voltage after integration COMP detection level AMS OUT AMS ON Fig. 6. Conceptual diagram of AMS OUT operation – 29 – CXA1878Q (2) AMS OFF operation When the input signal disappears, the capacitance connected to the AMS TC pin (Pin 37) is discharged, causing the TC pin voltage to rise above the threshold value and turn AMS OFF. (3) AMS gain setting method The AMS gain (G1/G2 mode gain) adjustment can be determined by external resistances R1 and R2. In addition, AMS gain is expressed by the following equations. G1 = 20 log R1 + 100kΩ (internal resistance) dB R1 G2 = 20 log R2 + 100kΩ (internal resistance) dB R2 dB [∗2] [∗1] G1 NOR (BS) G2 FF (AMS) [∗2] [∗1] Frequency (4) AMS low frequency cut-off setting method The AMS low frequency cut-off adjustment can be determined by external resistances R1 and R2 and capacitances C1 and C2. (5) Relationship between response time and sensitivity The AMS ON time is determined by the width of the pulse obtained by applying the input signal to the WINDOW comparator. The pulse emitted from the WINDOW comparator becomes extremely small near the detection level, and some time is required for this pulse to be integrated by the external capacitance, thus lengthening the response time. ∗ Response times can be adjusted to approximately the same value by adjusting the AMS sensitivity with resistances R1 and R2 to match the various ICs. Also, the AMS OFF time is determined by the external time constant (R3, C3). Notes on Operation Temperature characteristics and accuracy of the recording equalizer amplifier The temperature characteristics of the built-in monolithic filter and the filter cut-off frequency depend on the 27kΩ external resistance connected to the IREF pin (Pin 10). Also, the recording equalizer amplifier frequency response depends on unevenness in the absolute, as well as relative values of the internal capacitance. Furthermore, the high frequency response indicates a high element sensitivity at the filter because the band-pass filter Q is high. Compared to low frequency, although the unevenness inherent in the IC is more likely to occur, this occurs relatively, and not individually for channels 1 and 2. – 30 – CXA1878Q Example of Representative Characteristics Recording equalizer amplifier frequency response (NORMAL SPEED) Recording equalizer amplifier frequency response (HIGH SPEED) 30.0 20.0 VCC, VEE = ±7.0V 0dB = NORM - NORM, 315Hz, –23dBv (Output reference) (Tape) (Speed) NORM - NORM CrO 2 - NORM METAL - NORM Output response [dB] Output response [dB] 30.0 10.0 0.0 20.0 VCC, VEE = ±7.0V 0dB = NORM - NORM, 315Hz, –23dBv (Output reference) (Tape) (Speed) NORM - HIGH CrO 2 - HIGH METAL - HIGH 10.0 0.0 –10.0 –10.0 100 1k 10k 100k 100 Frequency [Hz] Output level vs. REC CAL pin voltage 8 8 315Hz 8kHz 6 4 2 0 VCC, VEE = ±7.0V (Tape) (Speed) MODE: NORM - NORM GP CAL pin = Open 0dB = REC CAL and GP CAL pin = Open –20dB (at 315Hz,–3dBv) –2 –4 –6 4 2 0 –2 –4 –6 –2.0 –1.0 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 REC CAL and GP CAL frequency response Output response [dB] 10.0 0.0 VCC, VEE = ±7.0V (Tape) (Speed) 0dB = NORM - NORM, 315Hz, –23dBv (Output reference) REC CAL and GP CAL = Open GP = 5.0V 2.5V 0.0V REC CAL = 5.0V REC CAL = 2.5V REC CAL = 0.0V –10.0 100 1k A AAAA AA VCC, VEE = ±7.0V (Tape) (Speed) MODE: NORM - NORM REC CAL pin = Open 0dB = REC CAL pin and GP CAL pin = Open –20dB (at 315Hz,–3dBv) GP CAL pin voltage [V] 40.0 20.0 315Hz 3kHz 8kHz 12kHz –2.0 –1.0 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 REC CAL pin voltage [V] 30.0 10k Output level vs. GP CAL pin voltage Output level [dB] Output level [dB] 6 1k Frequency [Hz] 10k 100k Frequency [Hz] – 31 – 100k CXA1878Q Output level vs. REC MUTE pin voltage 1 Output level vs. REC MUTE pin voltage 2 100 0 80 Output level [dB] Output level [%] –20 60 40 VCC, VEE = ±7.0V (Tape) (Speed) MODE: NORM - NORM, 0dB = 1kHz, +12dB (at 315Hz, –3dBv) f = 1kHz 20 0 VCC, VEE = ±7.0V (Tape) (Speed) MODE: NORM - NORM, 0dB = 1kHz, +12dB (at 315Hz, –3dBv) f = 1kHz –40 –60 –80 0.0 1.0 2.0 3.0 4.0 5.0 6.0 0.2 REC MUTE pin voltage [V] 1.0 2.0 5.0 Recording equalizer amplifier load characteristics Output level vs. REC MUTE pin voltage 3 15 Maximum output level (dB) 0 –20 Output level [dB] 0.5 REC MUTE pin voltage [V] –40 –60 –80 10 0 VCC, VEE = ±7.0V (Tape) (Speed) MODE: NORM - NORM, 0dB = 1kHz, +12dB (at 315Hz, –3dBv) f = 1kHz –100 VCC, VEE = ±7.0V (Tape) (Speed) MODE: NORM - NORM, 0dB = –3dBv (REC OUT pin) THD + N = 1% 315Hz 1kHz 5 100 1k 10k 100k Load resistance RL [W] Recording volume balance characteristics 0.0 1.0 2.0 3.0 4.0 5.0 6.0 0 REC MUTE pin voltage [V] –10 Recording volume output level [dB] Recording volume characteristics 0 Volume output [dB] –10 –20 –30 –40 –50 –60 –70 VCC, VEE = ±7.0V DVCC = +5.0V Input : VOLUME IN = –10dBv, f = 1kHz REC BAL pin voltage = 2.5V 0.5 1.0 2.0 –30 –40 –50 –60 –70 VCC, VEE = ±7.0V DVCC = +5.0V Input : VOLUME IN = –10dBv, f = 1kHz REC VOL pin voltage = +5.0V 1CH 2CH –80 –90 –100 –80 0.2 –20 0.0 5.0 1.0 2.0 3.0 4.0 Balance control pin voltage [V] REC LEVEL pin voltage [V] – 32 – 5.0 CXA1878Q Meter rectification output characteristics Level meter output characteristics (REC, PB mode) +13dB 1.0 0.1 VCC, VEE = ±7.0V DVCC = +5.0V PB mode: 0dB = –4dBv (LINE OUT) REC mode: 0dB = –7dBv (NR REC OUT) f = 1kHz 0.01 –60 –40 –20 0dB 1 –10dB –20dB 0.1 –30dB –40dB Playback equalizer amplifier distortion 10 1.0 T.H.D + N [%] Playback equalizer amplifier frequency response 25.0 120µs 17.0 10k Frequency [Hz] 0 21.0 1k 100 20 Input level [dB] Output response [dB] +10dB VCC, VEE = ±7.0V 0dB = –7dBv (NR REC OUT) Rectification voltage [V] Meter output voltage [V] 5.0 VCC, VEE = ±7.0V (Tape) (Speed) MODE = NORM - NORM 100Hz 1kHz 10kHz 0.1 70µs 60µs 13.0 9.0 VCC, VEE = ±7.0V (Tape) (Speed) 0dB = NORM - NORM, 315Hz, –31dBv (input reference) 0.01 35µs –30 –40 5.0 –20 –10 Input level [dBv] 100 1k 10k 100k Line amplifier THD + N Frequency [Hz] 10.0 Line amplifier frequency response (PASS mode) 10.0 Output response [dB] 1.0 VCC, VEE = ±7.0V MODE = PASS MODE 0dB = –4dBv (LINE OUT) 100Hz 1kHz 10kHz 8.0 6.0 0.1 4.0 2.0 0.0 VCC, VEE = ±7.0V 0dB = –11dBv (NR PB IN) PASS mode 100 1k 0.01 10k 100k Frequency [Hz] –16 –12 –8 –4 0 4 Output level [dB] – 33 – 8 12 16 CXA1878Q A.M.S/B.S mode frequency response VCC, VEE = ±7.0V 0dB = –11dBv AMS mode BS mode Input level [dB] 20 10 0 –10 –20 –30 100 1k Frequency [Hz] 10k BIAS SW load characteristics –6.4 Output voltage [V] –6.5 –6.6 –6.7 –6.8 VCC, VEE = ±7.0V –6.9 BIAS N BIAS C BIAS M –7.0 0 0.5 1.0 1.5 2.0 Output current [mA] Current consumption [mA] Supply voltage vs. Current consumption 38 37 36 35 34 5.0 6.0 7.0 Supply voltage [V] – 34 – 8.0 CXA1878Q Dolby B type NR encode boost 10 VCC, VEE = ±7V Dolby Level 400Hz, –6dBm Dolby C type NR encode boost –40dB 20 –60dB –55dB –50dB –45dB –40dB –35dB 8 Encode Boost [dB] Encode Boost [dB] –35dB –30dB 6 –25dB 4 –20dB –15dB –10dB –5dB 0dB (Dolby Level) 2 0 16 12 8 –30dB 4 –25dB –2 –4 1k 100 –20dB –15dB –10dB –5dB 0dB (Dolby Level) 0 VCC, VEE = ±7V Dolby Level 400Hz, –6dBm 10k Frequency [Hz] 100 1k 10k Frequency [Hz] Dolby NR OFF total harmonic distortion T.H.D + N [%] VCC, VEE = ±7.0V 0dB = –6dBm (NR REC OUT, NR OFF) Encode Mode 100Hz 1kHz 1 10kHz 0.1 0.01 –4 0 4 8 12 16 20 Output level [dB] Dolby C type NR total harmonic distortion Dolby B type NR total harmonic distortion 100Hz 1kHz 10kHz 1 T.H.D + N [%] T.H.D + N [%] VCC, VEE = ±7.0V 0dB = –6dBm (NR REC OUT, NR OFF) Encode Mode 100Hz 1kHz 1 10kHz 0.1 0.01 0.1 0.01 –4 0 4 8 12 16 20 VCC, VEE = ±7.0V 0dB = –6dBm (NR REC OUT, NR OFF) Encode Mode –4 Output level [dB] 0 4 8 12 Output level [dB] – 35 – 16 20 CXA1878Q Package Outline Unit: mm 64PIN QFP(PLASTIC) 23.9 ± 0.4 + 0.4 20.0 – 0.1 + 0.1 0.15 – 0.05 51 0.15 64 20 1 16.3 32 + 0.4 14.0 – 0.1 52 17.9 ± 0.4 33 + 0.2 0.1 – 0.05 0.8 ± 0.2 19 + 0.35 2.75 – 0.15 + 0.15 0.4 – 0.1 1.0 ± 0.12 M PACKAGE STRUCTURE PACKAGE MATERIAL EPOXY RESIN SOLDER/PALLADIUM PLATING SONY CODE QFP–64P–L01 LEAD TREATMENT EIAJ CODE QFP064–P–1420 LEAD MATERIAL 42/COPPER ALLOY PACKAGE MASS 1.5g JEDEC CODE – 36 –