NJU8721C NJR, NJU8721C Datasheet
NJU8721C
Specifications of NJU8721C
Related parts for NJU8721C
NJU8721C Summary of contents
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CLASS D HEADPHONE AMPLIFIER FOR DIGITAL AUDIO ! GENERAL DESCRIPTION The NJU8721 is a class D Headphone Amplifier th featuring 6 modulation. Attenuator, Mute, and De-emphasis circuits. converts digital source input to PWM signal output which is converted to analog ...
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NJU8721 ! BLOCK DIAGRAM V Power On DD Reset Circuit V SS Synchronization RST Circuit MCK LRCK Serial Audio Data BCK Interface DIN MUTE STBY System MODE Control F0/DATA F1/REQ F2/SCK - 32f ...
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TERMINAL DESCRIPTION No. SYMBOL QFN28 SSOP20 1 26 STBY 2 27 TEST SSR 4 2 OUT DDR DDL 7 6 OUT SSL 9 9 MODE 10 10 ...
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NJU8721 ! FUNCTIONAL DESCRIPTION (1) Signal Output PWM signals of L channel and R output from OUT converted to analog signal by external 2nd-order or over LC filter. The output driver power supplied from and ...
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System Control (6-1) Standby Standby functions by “L” level input to the STBY terminal. In busy of Standby, conditions of digital audio format set, attenuation level, de-emphasis, and attenuator operation time are kept and output terminals of OUT and ...
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NJU8721 (7) Serial Audio Data Interface (7-1) Input Data Format Selection The digital audio interface format is selected out of I bits data length. (7-2) Input Timing Digital audio signal data into DIN terminal is fetched into the internal shift ...
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LRCK BCK DIN 17 16 LRCK BCK DIN LRCK BCK DIN 0 (7-3) Failure of Synchronization Operation If the MCK clock fluctuates over than 10 clocks against the LRCK and failure of synchronization is detected the attenuation ...
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NJU8721 (8) Control Register When Control Mode is set to Serial control by the Mode terminal, the control register sets various modes. The Control Data is fetched by the rising edge of F2/SCK and is set into the control register ...
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DEMP0, DEMP1 DEMP0 and DEMP1 control De-Emphasis on/off and sampling frequency. DEMP1 (8-4) MUTE Mute operation is controlled by the “MUTE” as same as the MUTE terminal control. MUTE 0 1 (8-5) F0, F1, F2 ...
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NJU8721 ! ABSOLUTE MAXIMUM RATINGS PARAMETER Supply Voltage Input Voltage Operating Temperature Storage Temperature SSOP20 Power Dissipation QFN28 Note 1) All voltage values are specified as V Note 2) If the LSI is used on condition beyond the absolute maximum ...
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Note 6) Analog AC Characteristics Test System Analog AC characteristics test system is shown in Figure 6. The analog AC characteristics of NJU8721 nd is measured with 2 -order LC LPF on the test board and Filters in the Audio ...
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NJU8721 ! TIMING CHARACTERISTICS Master Clock Input MCK PARAMETER MCK Frequency MCK Pulse Width (H) MCK Pulse Width (L) Note 7) t shows the cycle of the MCK signal. MCKI Reset Input RST PARAMETER Reset Low Level Width Digital Audio ...
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Control Register Interface t RQS F1/REQ t SCH F2/SCK t SCK DAS PARAMETER F2/SCK Period F2/SCK Pulse Width (H) F2/SCK Pulse Width (L) F0/DATA Setup Time F0/DATA Hold Time F1/REQ Pulse Width (H) F2/SCK Setup Time ...
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NJU8721 ! APPLICATION CIRCUIT 0.1uF V 3. 10uF MCK Digital 13 BCK Audio 14 LRCK Data 15 DIN 9 MODE 19 F0/DATA 18 F1/REQ Mode 17 F2/SCK Control 10 RST 1 STBY 16 MUTE ...