cxa1797q Sony Electronics, cxa1797q Datasheet
cxa1797q
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cxa1797q Summary of contents
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... Dolby B-C Type Noise Reduction System with Recording Equalizer Amplifier Description The CXA1797Q is an audio signal processing LSI designed for use in cassette decks. Functions include Dolby B-C noise reduction, recording equalizer amplifier, meter circuit (logarithmic), bias control circuit, and playback switching circuit. Serial control of these functions is possible ...
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... R45 10k R40 VGS 2.8k (C) R38 2.5k R32 40k R22 VGS VGS (C) (C) VGS VGS (C) (C) 50k R4 50k R1 —2— CXA1797Q 10k 600 22k R57 3.3µ 150 R54 C18 4k R52 1.0µ C13 10k R43 4.7µ 100k C12 R41 8k R33 GND 0.068µ C8 0.1µ ...
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... CXA1797Q ...
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... Z (in) Equivalent circuit — 6. — 40k 147 — — — 147 —4— CXA1797Q = Description Recording volume 147 input buffer output Recording volume output 6.5k 147 V CC VCT Recording input Time constant for ...
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... DOLBY S IN2 (–6dBm) I/O Z (in) Equivalent circuit — — 147 — — 12k V EE 147 O 23.5k VCT —5— CXA1797Q Description V CC Time constant for the LLS V EE Line output 147 Dolby S NR output 147 V CC Dolby S NR input V EE ...
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... REC EQ OUT1 0.0V –4dBV 40 REC EQ OUT2 I/O Z (in) Equivalent circuit — 50k 147 VCT — — 8. — 50k V EE —6— CXA1797Q Description Recording output 147 V CC Recording equalizer amplifier input cut capacitance V EE Recording equalizer amplifier 147 output ...
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... I/O 17k 17k — 100p 4k 76.6k DGND V EE —7— CXA1797Q Description V CC Recording bias control voltage setting V EE Recording bias control voltage output Time constant for selecting NR mode Time constant for selecting B/C mode 147 Time constant for selecting S and ...
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... I — 2k DGND I — 4k DGND I — 147 I 100k DGND V EE —8— CXA1797Q Description Negative power supply (Connect to ground when using a single power supply) Positive power supply V CC Reset signal input (active low) 2.5V DGND Load signal input reference Clock input V EE ...
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... 54k 147 54k — DGND V EE DVCC —9— CXA1797Q Description Recording volume balance adjustment High-frequency gain adjustment of recording equalizer amplifier Peak frequency Q adjustment of recording equalizer amplifier Recording equalizer amplifier gain adjustment Logic power supply (DREF = 1/2 ...
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... Equivalent circuit V CC I/O 17k 17k 50k 147 VCT I 40k 147 — —10— CXA1797Q Description Time constant for selecting RECMUTE mode 147 V CC Recording volume input VCT Playback input V EE Head select output of playback 147 equalizer amplifier ...
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... Z (in) Equivalent circuit I 50k 147 VCT V CC — — — — — — 147 —11— CXA1797Q Description V CC Head select input of playback equalizer amplifier V EE Reference current of recording 147 equalizer amplifier V CC Ground (center capacitance when using a single power supply) ...
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... IN pin and then measure the relative deviation from NORM-NS, 315 Hz mode. METAL-tape, NORM-speed mode Input a 12 kHz signal (-20 dB level down) to the REC EQ IN pin and then measure the relative deviation from NORM-NS, 315 Hz mode. —12— CXA1797Q = 5 5 Specifications Unit Min. Typ. Max. ± ...
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... 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-tape, NORM-speed mode With no signal, measure the DC offset voltage of the REC OUT pin. —13— CXA1797Q Specifications Unit Min. Typ. Max. –6.2 –5.2 –4.2 dB –0.5 1 ...
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... Input a 1 kHz signal and set the input level so that the THD is 1%. (Measure the distortion when the output is +2 dBv.) REC-VOL = 2.0 V, REC-BAL = 2 2.7 k Input a 1 kHz, -10 dBv signal (reference input level) and measure the distortion. (Measure the distortion as THD + N.) —14— CXA1797Q Specifications Unit Min. Typ. Max. — –88.0 –80.0 dB 4.6 6 ...
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... Alternately input a 1 kHz, -18 dBm signal to the DOLBY PB IN pin and measure the channel crosstalk. (Use a 1 kHz BPF.) METER ON, REC mode Input a 1 kHz, -26 dBv signal to the REC IN pin and measure the output DC voltage at the METER pin. —15— CXA1797Q Specifications Unit Min. Typ. Max. 80.0 83.0 — dB – ...
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... DC voltage of the BIAS OUT pin. METAL mode Set the external feedback resistance and and measure the output DC voltage of the BIAS OUT pin. —16— CXA1797Q Specifications Unit Min. Typ. Max. 2.75 3.05 3.35 V 1.85 2.15 2. ...
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... Input a 1 kHz, +10 dB signal to the REC IN pin and measure the distortion. (Measure the distortion as THD + N.) REC, Dolby B mode Input a 1 kHz, +10 dB signal to the REC IN pin and measure the distortion. (Measure the distortion as THD + N.) —17— CXA1797Q Specifications Unit Min. Typ. Max. — –6.0 — ...
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... With no signal, measure the deviation in the output DC offset voltage at the REC OUT pin when switching from NR off mode to C type mode. ViH ViL fck tw tsu(DATA CLK) tH(CLK DATA) tw(DATA) ts(LATCH DATA) tH(CLK LATCH) tw(XRST) —18— CXA1797Q Specifications Unit Min. Typ. Max. — 0.08 0.3 % 60.0 61.0 — dB — –79 –70 dB — ...
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... S55 R99 4.7µ 10k C41 B/C TC S57 R101 4.7µ 10k C43 METER S59 OUT1 R103 3.3µ 10k GND CXA1797Q —19— 100k GND C12 0.1µ BUFFER OUT2 C14 VOLUME OUT2 0.1µ C16 S23 -25dBm REC IN2 0.1µ C18 S25 DOLBY TCH2 0.1µ ...
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... CXA1797Q ...
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... Description of Operation 1. Logic Usage The CXA1797Q is controlled by 11-bit serial data. Name D1 SPEED D2 METAL A/B D5 METER D6 PB/REC D7 LMUTE D8 RMUTE D9 BC/S (Note 1) D10 B/C D11 NR ON/OFF Note 1) S mode takes precedence over other noise reduction modes. (When turning noise reduction off, select BC mode.) Note 2) All data is initialized to "1" when a reset is executed. ...
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... Timing Chart of 11-bit Serial Data Interface CLK 3.5V DATA 1.5V t SLD LATCH 1.5V CLK D10 DATA LATCH XRESET 3.5V 1. SDK HCD 3.5V t HLC t HCL D11 3.5V 1.5V 1. —22— CXA1797Q ...
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... This pin adjusts the middle/high frequency gain for the recording equalizer amplifier. (The gain is at the center when voltage of (DV Low-frequency boost (external) + DGND)/2 is applied to this pin or when DGND)/2 is applied to this pin or when it is open DGND)/2 is applied to this pin or when it is open.) CC GP/ Frequency (Hz) —23— CXA1797Q RECCAL ...
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... In addition, these functions can be controlled directly by applying voltage from an external source. (In this case, the capability to drive 17 k impedance is required.) 6. Meter circuit The CXA1797Q meter circuit is a logarithmic detector. The circuit has a sensitivity of 65 mV/dB and is designed to generate 2.8 V when the reference signal is input. ...
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... Output level (dB) REC EQ frequency response 1k 10k Frequency (Hz) 14 ±5. NORM Tape—NORM SPEED 12.0 0dB = —4dBV THD 10.0 8.0 6.0 4.0 2.0 0 100 500 8 12 —25— CXA1797Q 100k REC EQ load characteristics f=315Hz f=1kHz 1k 5k 10k 50k 100k Load resistance ( ) ...
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... GH = 2.5V –10 10 100 1k Frequency (Hz) FQ CAL frequency response ±5. NORM Tape—NORM SPEED REC CAL and GH CAL: open 0dB = 315Hz, —24dBV CAL = 5.0V 0 –10 10 100 1k Frequency (Hz) —26— 100k 10k 100k 10k FQ CAL = 0V FQ CAL = 2.5V 100k 10k CXA1797Q ...
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... Output level vs. FQ CAL voltage 8 NORM Tape—NORM SPEED REC CAL, GH CAL = 2.5V 6.0 0dB = REC CAL, FQ CAL, GH CAL: open —20dB (at 315Hz, —4dBv) 4.0 2.0 0 –2.0 –4.0 –8.0 0 1.0 2.0 FQ CAL pin voltage (V) —27— 3.0 4.0 5.0 315Hz 3kHz 8kHz 12kHz 3.0 4.0 5.0 =±5.5V 315Hz 3kHz 8kHz 12kHz 3.0 4.0 5.0 CXA1797Q ...
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... REC balance control voltage (V) REC VOL total harmonic distortion ±5. REC LEVEL: 2.0V 0dB = –10dBV f = 1kHz 1.0 0.1 0.01 –8 –4 0 Output level (dB ±5. NORM Tape—NORM SPEED REC CAL, FQ CAL, GH CAL = 2.5V 0dB = REC LEVEL = 5.0V BALANCE = 2.5V Output for –10dBv input —28— CXA1797Q ...
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... Frequency (Hz type total harmonic distortion 2 ±5. Encode Mode 0dB = Dolby Level 1.0 0.5 0.2 0.1 f=100Hz 0.05 f=1kHz f=10kHz 0.02 0.01 18 – Output level (dB) —29— CXA1797Q –60dB –50dB –40dB –30dB –20dB –10dB 0dB 2k 5k 10k ...
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... Rejection on Split Supply =± 5. off encoding mode 0 NR off decoding mode NR B encoding mode NR B decoding mode – encoding mode $ NR C decoding mode –20 – –40 –50 –60 100 200 500 1k Frequency (Hz) $ 10k —30— CXA1797Q $ $ $ $ $ 2k 5k 10k ...
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... SONY CODE EIAJ CODE JEDEC CODE 64PIN QFP(PLASTIC) 23.9 ± 0.4 + 0.4 20.0 – 0 0.15 0.4 – 0.1 2.75 – 0.15 M ± 0.12 PACKAGE STRUCTURE PACKAGE MATERIAL LEAD TREATMENT QFP–64P–L01 LEAD MATERIAL QFP064–P–1420 PACKAGE WEIGHT —31— CXA1797Q + 0.1 0.15 – 0.05 0.15 + 0.2 0.1 – 0.05 + 0.35 EPOXY RESIN SOLDER/PALLADIUM PLATING COPPER /42 ALLOY 1.5g ...