QS7785 NPC [Nippon Precision Circuits Inc], QS7785 Datasheet
QS7785
Related parts for QS7785
QS7785 Summary of contents
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... NIPPON PRECISION CIRCUITS INC. OVERVIEW The QS7785PF/ audio processor IC that generates 2, 4, 5-channel stereo surround signals from 2-channel stereo or mono sources using QSur- round™ technology developed and licensed by QSound Labs, Inc. FEATURES Surround signal output for 2-channel front speak- ...
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... BLOCK DIAGRAM 36 BASC1 37 RIN 38 LIN 39 BASC2 40 MSC6 41 MSC5 42 MSC4 43 MSC3 44 MSC2 45 MSC1 31 VCC To internal 19 VREFIN 6 GND 17 18 QS7785PF/CF 0.35max 0.10 0. Front QEXPANDER Surround QEXPANDER To internal Multiplex/Decode/Level Shift 1.00typ 0.339typ 0.50 0. FROUT ...
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... I Input mode control (HIGH: parallel, LOW: serial) I Enhancement control (HIGH: high spread, LOW: low spread) I Serial data strobe (not applicable to QS7785CF) I Mono-to-stereo convert select (HIGH: mono to stereo mode, LOW: normal mode) I Center output control (HIGH: center on, LOW: center off) I ...
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... I C signal input voltage (SDA, SCL) Power dissipation Storage temperature range Recommended Operating Conditions GND = 0V Parameter Supply voltage range (analog) Supply voltage range (digital) Operating temperature range QS7785PF/CF I/O Description I Right-channel signal input I Left-channel signal input I Bass boost left-channel signal input I Mono/stereo conversion filter capacitor 6 I Mono/stereo conversion fi ...
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... Symbol Bypass noise voltage N Qsurround noise voltage (front) N Qsurround noise voltage (surround) N Bypass total harmonic distortion THD Qsurround mono total harmonic THD distortion QS7785PF/CF Condition LIN, RIN AIN1 CIN AIN2 IH IL Digital inputs, V input voltage DD SDA, SCL, 10V input voltage ACK signal output from SDA, 3mA sink ...
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... BYP = SP = LOW, MONO = SUR = HIGH, MSL LIN = RIN, SLOUT 1kHz BYP = SP = LOW, MONO = SUR = HIGH, MSR LIN = RIN, SROUT 1kHz t QS7785PF 0 t QS7785PF 1 t QS7785PF 2 t QS7785PF 3 t QS7785PF 4 t QS7785PF 5 t QS7785PF 6 t QS7785PF 7 Rating Unit min typ max 1.7 2.3 – V RMS 1.8 2.4 – V RMS 1 ...
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... Data signal. Sets mode settings. See “Operating Modes.” SCL Clock signal. Data is read on the rising edge. STRB Strobe signal. Mode switches occur on the rising edge of this signal 2-wire (QS7785CF) timing I C address is {AD6 − AD0} = {1011011} 2 SDA AD6 AD0 t ...
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... FUNCTIONAL DESCRIPTION Operating Modes The QS7785PF/CF operating mode can be con- trolled over either a parallel interface (P/S = HIGH) or one of two serial interfaces (P/S = LOW). The Output mode No. Input signals 1 2 Stereo only Mono only Stereo/Mono 11 12 Stereo only 1. – (dash output signal. ...
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... When PSAVE is HIGH, the analog stages of the device are turned OFF to save power. When MUTE is HIGH, all outputs are muted. QS7785PF/CF on both front and surround speakers. In mode 11, the stereo signal is output on surround speakers only. In output mode 12, the input stereo signal is output on front speakers, and a surround effect enhanced signal is output on the surround speakers ...
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... Speaker Arrangement The QS7785PF/CF supports the following speaker arrangements. 37 RIN SROUT 24 38 LIN FROUT 26 CIN 21 Speakers COUT 22 FLOUT 25 SLOUT 23 Type A. Two front speakers in front and two surround speakers in rear 37 RIN SROUT 24 38 LIN FROUT 26 CIN 21 COUT 22 FLOUT 25 SLOUT 23 Type C. Front speakers and surround speakers in ...
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... Gain −6dB G C Note: Internal resistance value, R1 and R2, may vary ± 15%. QS7785PF/CF Adding to the front-channel output With this connection, the bass frequency components can be removed from a signal. Capacitors Ca and Cb and resistor Ra can be connected between CIN and COUT to form a highpass filter. The −3dB cutoff fre- quency of the fi ...
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... When BASS is HIGH, resistors RA and RB and + RA=10k C:0.15µF Bass boost connection (Gb = 6dB Gain G b 0dB QS7785PF/CF capacitor C are connected to form a lowpass filter. The lowpass filter signal and the original signal (RIN, LIN) are combined to boost bass frequencies. RIN /LIN R1:20k R2:20k 37 RB:10k ...
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... QXCC2 QXCC3 8200pF A capacitor for decoupling should be connected between supply and ground. QS7785PF/ 13V 0.01µF 0.01µF 3300pF 3300pF 10k 0.15µF RIN 37 LIN 38 39 BASC2 40 MSC6 41 MSC5 ...
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... QXCC2 QXCC3 8200pF A capacitor for decoupling should be connected between supply and ground. QS7785PF/ 13V 0.01µF 0.01µF 3300pF 3300pF BASC2 40 MSC6 41 MSC5 42 MSC4 43 MSC3 44 ...
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... Customers shall not export, directly or indirectly, any products without first obtaining required licenses and approvals from appropriate government agencies. NIPPON PRECISION CIRCUITS INC. QS7785PF/CF NIPPON PRECISION CIRCUITS INC. 4-3, Fukuzumi 2-chome Koto-ku, Tokyo 135-8430, Japan ...