cxa1878q Sony Electronics, cxa1878q Datasheet
cxa1878q
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cxa1878q Summary of contents
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... 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. ...
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... CXA1878Q ...
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... Equivalent circuit 40k 1 I 40k 51 300 2 O — 300 50 330k 13k — — 3 36k 49 13.5k — — 480k – 3 – CXA1878Q = 7.0V –7.0V 5.0V Description GND 1.5k Recording equalizer amplifier input 3.4k Line output Time constant for the HLS Time constant for the LLS ...
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... I/O Z (in) Equivalent circuit 192 5 O — 20k 192 40k 46 40k GND 9.5k I 50k 7 45 50k GND 211 22. — 211 44 – 4 – CXA1878Q Description 12k Dolby S type NR output 1.5k GND Dolby S type NR input Recording equalizer amplifier input Dolby NR recording signal output 1.5k GND ...
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... O — – 5 – CXA1878Q Description Recording equalizer amplifier output Reference current setting for built-in recording/playback equalizer amplifier The reference current can be set by connecting a resistor between this pin and Reference current setting for built-in Dolby ...
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... I — 10k — – 6 – CXA1878Q Description Recording bias control voltage output 100k 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 ...
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... I — I — 23 10k I — 10k I — 24 – 7 – CXA1878Q Description Tape speed selection Normal speed/ double speed selection High: Double speed Low : Normal speed DGND Recording/playback mode control Recording/playback mode selection High : Recording mode Low : Playback mode Positive power supply ...
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... I 100k 28 40k GND 8k 21k 70k 29 I 100k 30k – 8 – CXA1878Q Description Playback deck A/B select control Playback equalizer amplifier input selection High: PB INB Low : PB INA DGND Level meter amplifier output Recording volume level control High: Output signal level increased Low : Output signal ...
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... 50k 50k – 9 – CXA1878Q Description Negative power supply Recording equalizer amplifier high frequency calibration Controlled with DC voltages 5V. High: High frequency level gain increased Low : High frequency level gain reduced Leave this pin open ...
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... AMS FB 0.0V — — I/O Z (in) Equivalent circuit O — 36 10k 10k 10k DGND 37 — — — — 38 100k 2p — — 39 100k – 10 – CXA1878Q Description AMS amplifier output Time constant for the 40k AMS Feedback during AMS mode Feedback during BS mode ...
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... I — 500 O 64 500 50k 53 – 11 – CXA1878Q Description GND 1.5k Calibration signal input Recording mute ON/OFF selection The recording mute is controlled with DC voltages 5V. High: Recording mute OFF GND Low : Recording mute ON Soft mute and fader functions can be set by ...
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... PB INA2 56 PB INB2 — 58 GND 0.0V I/O Z (in) Equivalent circuit I 40k 62 54 500 I — 61 500 55 GND 59 60 50k 57 I 50k 56 — — – 12 – CXA1878Q Description Dolby NR playback input 35.5k 2. GND GND 8p Playback equalizer amplifier output 30k Playback equalizer amplifier input Ground ...
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... CXA1878Q –3dBv –7dBv –24dBv –7dBv –7dBv –4dBv –26dBv ...
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... CALIBRATION REC BALANSE & LEVEL REC – 14 – CXA1878Q MICROCOMPUTER to ...
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... Ternary swithing Binary – 23 – CXA1878Q ...
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... 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. ...
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... NORMAL CrO 2 DOLBY NR MUTE METER ON — Min. Max. 4 2.2 2.8 0.0 0.5 3 0.0 0.5 – 25 – CXA1878Q Remarks High DOLBY NR ON 3-state C type CALIBRATION 3-state BS MODE 3-state REC 2-state HIGH SPEED 2-state 2-state 70µ 2-state 70µ REC EQ METAL 2 3-state BIAS SW ...
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... 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 ...
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... 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 DV (A 0dB signal is output when voltage of 2.0V is applied.) 3 Typ ...
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... 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 DV 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 applied ...
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... AMS circuit The CXA1878Q has the music sensor circuit. 0dB NR PBIN1 62 0dB NR PBIN2 54 16kHz LPF [ 2] (1) AMS ON operation The signal input from 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 ...
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... 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 100k (internal resistance 100k (internal resistance NOR (BS (AMS Frequency – 30 – CXA1878Q [ 1] ...
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... Output level vs. GP CAL pin voltage ±7.0V EE –2 (Tape) (Speed) –4 GP CAL pin = Open –6 GP CAL pin = Open –2.0 10k 100k – 31 – CXA1878Q (HIGH SPEED) = ±7.0V EE (Tape) (Speed) NORM - HIGH CrO - HIGH 2 METAL - HIGH 100 1k 10k Frequency [Hz] 315Hz 3kHz 8kHz 12kHz ...
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... Recording volume balance characteristics 0 –10 –20 –30 –40 –50 –60 – ±7. +5.0V CC –80 Input : VOLUME IN = –10dBv 1kHz –90 REC VOL pin voltage = +5.0V 1CH 2CH –100 0.0 1.0 2.0 5.0 Balance control pin voltage [V] – 32 – CXA1878Q 1.0 2.0 5 ±7.0V EE (Tape) (Speed) 315Hz 1kHz 10k 100k [W] L 3.0 4.0 5.0 ...
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... MODE = PASS MODE 0dB = –4dBv (LINE OUT) 1.0 0.1 0.01 10k 100k –16 –12 –8 – 33 – CXA1878Q +13dB +10dB = ±7.0V 0dB –10dB –20dB –30dB –40dB 1k 10k Frequency [Hz ±7.0V EE (Tape) (Speed) 100Hz 1kHz 10kHz –30 –20 – ...
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... Frequency [Hz] BIAS SW load characteristics –6.4 –6.5 –6.6 –6.7 V –6.8 –6.9 –7.0 0 0.5 1.0 Output current [mA] Supply voltage vs. Current consumption 5.0 6.0 7.0 Supply voltage [V] – 34 – ±7. 0dB = –11dBv AMS mode BS mode 10k , V = ±7. BIAS N BIAS C BIAS M 1.5 2.0 8.0 CXA1878Q ...
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... Dolby C type NR total harmonic distortion 100Hz 1kHz 10kHz 1 0 0dB = –6dBm (NR REC OUT, NR OFF) 0.01 Encode Mode 20 –4 0 – 35 – CXA1878Q –60dB –55dB –50dB –45dB –40dB –35dB –30dB –25dB –20dB –15dB –10dB = ±7V –5dB 0dB (Dolby Level) 1k 10k Frequency [Hz] = ±7.0V ...
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... SONY CODE EIAJ CODE JEDEC CODE 64PIN QFP(PLASTIC) 23.9 ± 0.4 + 0.4 20.0 – 0 0.15 + 0.35 0.4 – 0.1 2.75 – 0.15 M ± 0.12 PACKAGE STRUCTURE PACKAGE MATERIAL EPOXY RESIN SOLDER/PALLADIUM QFP–64P–L01 LEAD TREATMENT LEAD MATERIAL 42/COPPER ALLOY QFP064–P–1420 1.5g PACKAGE MASS – 36 – CXA1878Q + 0.1 0.15 – 0.05 0.15 + 0.2 0.1 – 0.05 PLATING ...