[ASAHI KASEI] [AK7714] AK7714 20-Bit Audio Codec with DSP and Delay RAM General Description The AK7714 is a highly integrated audio processing IC with 20-bit stereo ADC and 4-channel DAC plus on-chip DSP with 64-kbit delay RAM. The built-in ADC has a dynamic range of 99 dB with S/(N+D) of 92 dB, and the DAC has a dynamic range of 98 dB with S/(N+D) of 89 dB, thereby ensuring high performances. The AK7714 is compatible with each of the sampling frequencies of 48 kHz, 44.1 kHz or 32 kHz, and a program of 512 steps (when sampling at 44.1 kHz or 32 kHz) can be executed in one sampling time. The AK7714 is a programmable audio DSP containing RAM for delay. This allows sound field control programs to be implemented for surround sound, echo 3D, parametric equalizer and the like. Furthermore, the AK7714 uses a small 100-pin LQFP package, providing the optimum system for the sound field of car audio equipment which is required to meet space saving requirements. Features DSP: Word length: 24-bit (Data RAM) Instruction cycle time: 44.2 ns Multiplier: 24 x 16 40-bit Divider: 24 / 24 16-bit ALU: 34-bit arithmetic operation (Overflow margin: 4 bits) 24-bit arithmetic and logic operation 1, 2, 3, 4, 8 and 15 bits shifted left - Shift+Register: 1, 2, 3, 4, (6, 14), 8 and 15 bits shifted right ( )Numbers in parentheses are restricted. Provided with indirect shift function 448 x 32-bit - Program RAM: - Coefficient RAM: 384 x 16-bit 128 x 24-bit - Data RAM: - Internal delay memory: 4096 x 16-bit or 2048 x 24-bit 32 kHz to 48 kHz - Sampling frequency: - Serial micro controller interface 512/384/256 fs (512 fs for sampling at 44.1 kHz or 32 kHz) - Master clock: - Master/slave operation - Serial signal input port (2 to 6 ch), output port (2 to 6 ch) : 16/20/24-bit ADC: 2 channels - 20-bit 64 x Over-sampling delta sigma - DR, S/N : 99 dB - S/(N+D) : 92 dB - Digital HPF (fc = 1 Hz) DAC: 4 channels - 20-bit 128 x Over-sampling delta sigma - DR, S/N : 98 dB - S/(N+D) : 89 dB Others + 5 V 5% - Power voltage: - Operating temperature range: -40C to +85 C Package: 100-pin LQFP (0.5 mm pitch) - M0018-E-00 -1- `98/07 [ASAHI KASEI] [AK7714] Block diagram For standard operation (Internal connection mode, C3 to C7: initial settings) * CPCL * C3 C7 :L Internal connection mode :All 0 (Initial settings) This block diagram is a simplified illustration of the AK7714; it is not a circuit diagram. M0018-E-00 -2- `98/07 [ASAHI KASEI] [AK7714] Block Diagram of AK7714 DSP Section M0018-E-00 -3- `98/07 [ASAHI KASEI] [AK7714] Description of Input/Output Pins (1) Pin layout Note: M0018-E-00 Items enclosed in boxes are provided with pulldown functions. -4- `98/07 [ASAHI KASEI] [AK7714] (2) Pin function Pin No. Pin name I/O 3 TESTI1 I 4 TESTI2 I 5 TESTI3 I 6 TESTI4 I 7 DVB - 9 DVDD - 10,11 DVSS - 12 SDINA I 14 SDOUTA O 15 SDOUTD1 O 17 SDIND1 I 18 SDIND2 I 20 SDOUTD2 O 21 SDOUT O Function Test pin: Leave open or connect to DVSS. (Pulldown) Classification Test Test pin: Leave open or connect to DVSS. (Pulldown) Test pin: Leave open or connect to DVSS. (Pulldown) Test pin: Leave open or connect to DVSS. (Pulldown) +5 V power supply (Silicon substrate potential) Power supply +5 V Digital power supply Digital ground M0018-E-00 DSP Serial data input pin (Pulldown) OPCL="L": Disabled. Leave open or connect to DVSS. OPCL="H": Compatible with MSB first 24 bits ADC Serial data output pin OPCL="L": Outputs "L". OPCL="H": Outputs MSB first 20-bit data. DSP Serial data output pin OPCL="L": Outputs "L". OPCL="H": Outputs MSB first 24-bit data. DAC1 Serial data input pin (Pulldown) OPCL="L": Disabled. Leave open or connect to DVSS. OPCL="H": Compatible with MSB first 20 bits DAC2 Serial data input pin (Pulldown) OPCL="L": Disabled. Leave open or connect to DVSS. OPCL="H": Compatible with MSB first 20 bits DSP Serial data output pin OPCL="L": Outputs "L". OPCL="H": Outputs MSB first 24-bit data. DSP Serial data output pin Outputs MSB first 24-bit data. -5- Digital section Serial input/output data `98/07 [ASAHI KASEI] [AK7714] Pin No. Pin name I/O 23 SDIN1 I Function DSP Serial data input pin (Pulldown) Compatible with MSB first/LSB first 24, 20 and 16 bits Classification Digital section Serial input data 24 SDIN2 I DSP Serial data input pin (Pulldown) Compatible with MSB first/LSB first 24, 20 and 16 bits 27 XTI 28 XTO 30,31 DVSS System clock Master clock input pin Connect a crystal oscillator between this pin and the XTO pin, or input the external CMOS clock signal XTI pin. The clock frequency can be selected by the CKS0 and CKS1 pins. Crystal oscillator output pin O When a crystal oscillator is used, connect it between the XTI pin and this pin. When the external clock is used, keep this pin open. Digital Ground Power supply - 32,33 DVDD - 34 OPCL 35 CLKO 36 LRCLK 37 BITCLK 39 DRDY 40 SO 41 RDY I +5 V Digital Power supply M0018-E-00 ADC/DAC connection selector pin (Pulldown) OPCL="L" (Leave open or connect to DVSS.): Connected OPCL="H": Disconnected Clock output pin O Outputs the XTI clock. Allows the output to be set to "L" using the CTRL0 and CTRL1 pins. LR channel select Clock pin I/O SMODE="L": Slave mode: Inputs the fs clock. SMODE="H": Master mode: Outputs the fs clock. Serial bit clock pin I/O SMODE="L": Slave mode: Inputs 64 fs or 48 fs clocks. SMODE="H": Master mode: Outputs 64 fs clocks. Output data ready pin for microcomputer interface. O Control I Others System clock Microcomputer interface Serial data output pin for microcomputer interface (compatible with Hi-Z) O Hi-Z state is obtained when CS ="H". Data write ready output pin for microcomputer interface (compatible with Hi-Z) O Hi-Z state is obtained when CS ="H". -6- `98/07 [ASAHI KASEI] [AK7714] Pin No. Pin name I/O Function Digital Ground 42,43 DVSS - 44,45 DVDD - 47 WRQ I 48 CS I 49 JX I 53 SI I 55 SCLK I 56 CTRL0 I Classification Power supply +5 V Digital power supply Microcomputer interface Write Request pin Microcomputer interface chip selector input pin (Pulldown) Also used for SO control in addition to chip selection. When only one AK7714 is used and SO is not used, CS="L" may be used unchanged. SO and RDY will be Hi-z when CS ="H". External condition jump pin (Pulldown) Microcomputer interface serial data input pin (Pulldown) Microcomputer interface Program control Microcomputer interface Microcomputer interface serial data clock input pin 57 DSP RESET I 58 CODEC RESET I 59 INIT RESET I M0018-E-00 Clock output control pin (Pulldown) Use of CTRL0 and CTRL1 allows the CLKO output and LRCLK/BITCLK outputs in the master mode to be fixed to "L" or "H". See Function Description. Control CTRL1 CTRL0 CLKO LRCLK BITCLK 0 0 Output Output Output 1 0 "L" Output Output 1 1 "L" "H"("L") "L" Reset Reset pin Normally, DSP RESET and CODEC RESET are simultaneously controlled for use. Reset pin (for initialization) Used to input "L" to initialize the AK7714 at power-on. -7- `98/07 [ASAHI KASEI] [AK7714] Pin No. Pin name I/O Function Classification Test Test pin: Leave open. 61 TESTOUT O 62 CTRL1 I 63 CKS0 I 64 CKS1 I 65 SMODE I 66,67 DVSS - 68 DVDD - 70,71 DVB - 73 AOUTR2 O 74 AOUTL2 O 77 AOUTR1 O 78 AOUTL1 O 80 AVB - 82 VRDAL I Clock output control pin (Pulldown) Use of CTRL0 and CTRL1 allows the CLKO output and LRCLK/BITCLK outputs in the master mode to be fixed to "L" or "H". See CTRL0 ( pin 56 ) & Function Description. Clock selector pin CKS1 0 CKS0 0 XTI 384fs 0 1 512fs 512fs 1 0 256fs 256fa 1 1 Control DSP 384fs Test mode (disabled) Slave/master mode selector pin Set LRCLK and BITCLK to input or output mode. SMODE="L": Slave mode (LRCLK and BITCLK are set to input mode.) SMODE="H": Master mode (LRCLK and BITCLK are set to output mode.) Digital ground Power supply Power supply pin for digital section 5 V (typ) +5 V Digital power supply +5 V Power supply (normally analog) DAC2 Rch analog output pin (Silicon substrate potential) Analog section DAC2 Lch analog output pin DAC1 Rch analog output pin DAC1 Lch analog output pin +5 V power supply M0018-E-00 (Silicon substrate potential) Power supply DAC Reference voltage input pin Normally, connect to AVSS (pin 83). -8- Analog section `98/07 [ASAHI KASEI] [AK7714] Pin No. Pin name I/O Function Classification Power supply Analog ground 0V 83 AVSS - 84,85 AVDD - 86 VRDAH 87,88 VCOM 89 VRADL 90 AVSS - 91,92 AVDD - 93 VRADH I 95 AINR- I 96 AINR+ I 98 AINL- I 99 AINL+ I Power supply pin for analog section 5 V (typ) (Silicon substrate potential) +5 V Analog power supply DAC Reference voltage input pin Normally, connect to AVDD (pin 84,85), and connect 0.1 F and 10 F capacitors between this and VRDAL. Common voltage pin for analog section O Connect 0.1 F and 10 F capacitors between this and AVSS. Do not use for the external circuit. ADC Reference voltage input pin I Normally, connect to AVSS (pin 90). Analog section I Power supply Analog Ground 0V +5 V Analog Power supply (Silicon substrate potential) Analog section ADC Reference voltage input pin Normally, connect to AVDD (pin 91,92), and connect 0.1 F and 10 F capacitors between this and VRADL. ADC Rch analog inverted input pin ADC Rch analog non-inverted input pin ADC Lch analog inverted input pin ADC Lch analog non-inverted input pin Pin No. Pin name 1,2,8,13,16,19,22,25,26,29,38 46,50,51,52,54,60,69,72,75,76 NC 79,81,94,97,100 M0018-E-00 I/O - Function NC ( No connection ) These pins should be left floating. -9- Classification NC `98/07 [ASAHI KASEI] [AK7714] Absolute maximum rating (AVSS, DVSS = 0 V: All voltages indicated are relative to the ground.) Item Symbol Min Max Unit Power supply voltage Analog (AVDD), Boards (DVB and AVB) VA -0.3 6.0 V Digital (DVDD) (Note 1) VD -0.3 6.0 or (VA+0.3) V Input current (except for power supply pin ) IIN -10 +10 mA Analog input voltage VINA V AINL+, AINL-, AINR+, AINR-, -0.3 VA+0.3 VRADH, VRADL, VRDAH, VRDAL Digital input voltage (Note 1) VIND -0.3 VA+0.3 V Operating ambient temperature Ta -40 85 C Storage temperature Tstg -65 150 C Note: 1. Must not exceed the maximum rating of 6.0 V (namely, VD (VA+0.3 V) 6.0 V). (VA is a power supply to supply silicon substrate potential.) WARNING: Operation at or beyond these limits may result in permanent damage of the device. Normal operations are not guaranteed under these critical conditions in principle. Recommended operating conditions (AVSS, DVSS = 0 V: All voltages indicated are relative to the ground.) Items Symbol Min Typ Max Power supply voltage Board (AVB, DVB), AVDD VA 4.75 5.0 5.25 DVDD VD 4.75 5.0 VA Reference voltage (VREF) VRADH, VRDAH VRH VA VRADL, VRDAL VRL 0.0 Unit V V V V Note: 1. Start up VA simultaneously with or earlier than VD, and stop VD simultaneously with or earlier than VA. 2. When starting and stopping the power supply, meet the absolute maximum rating condition: VD (VA+0.3 V). It is generally recommended to use at VD VA. However, the VD must be 4.75 volts or more. 3. The analog input voltage and output voltage are proportional to the VRADH and VRDAH voltages. M0018-E-00 - 10 - `98/07 [ASAHI KASEI] [AK7714] Electric characteristics (1) Analog characteristics (Unless otherwise specified, Ta = 25C; AVDD, DVDD, AVB, DVB = 5.0 V; VRADH = AVDD, VRADL = AVSS, VRDAH = AVDD, VRDAL = AVSS; fs = 44.1 kHz; BITCLK = 64 fs ; XTI = 256 fs; Signal frequency 1 kHz; measuring frequency = 10 Hz to 20 kHz; 20 bits; DSP section in the reset state; ADC with all ifferential inputs ) Parameter Resolution Dynamic characteristics S/(N+D) (-0.5 dB) (Note 1) Dynamic range (A filter ) (Note 2) S/N (A filter ) Inter-channel isolation (f =1 kHz) DC accuracy Inter-channel gain mismatching Gain drift Analog input Input voltage (Note 3) Input impedance Resolution Dynamic characteristics S/(N+D) (0 dB) Dynamic range (-60 dB) (A filter) (Note 2) S/N (A filter) Inter-channel isolation (f = 1 kHz) (Note 4) DC accuracy Inter-channel gain mismatching (Note 4) Gain drift Analog output Output voltage (Note 5) Load resistance ADC section DAC section Note: Min Typ 86 94 94 90 92 99 99 105 1.9 Max 20 dB dB dB dB 0.1 50 0.3 dB ppm/C 2.0 220 2.1 Vp-p k Bits 20 83 93 93 90 2.70 5 Unit Bits 89 98 98 105 dB dB dB dB 0.2 50 0.5 dB ppm/C 2.95 3.20 Vp-p k 1. Single end input will result in poorer characteristics. 2. Indicates S/(N+D) when -60 dB signal is input. 3. The full scale for analog input voltage (AIN = (AIN+) - (AIN-)) can be represented By (FS = (VRADH-VRADL) x 0.4). 4. Specified for L and R of each DAC. 5. The full-scale voltage (0 dB) and output voltage are proportional to VRDAH voltage. Analog output voltage (Typ. @ 0 dB) = 2.95 Vpp*VRDAH/5 M0018-E-00 - 11 - `98/07 [ASAHI KASEI] [AK7714] (2) DC characteristics (VDD = AVDD = DVDD = AVB = DVB = 5.0 V 5%, Ta = 25C) Parameter High level input voltage (Note 1) Input pins other than XTI and test pins XTI and test pins Low level input voltage (Note 1) Input pins other than XTI and test pins XTI and test pins High level output voltage Iout=-100A Low level output voltage Iout=100A Input leak current (Note 2) Input leak current Pulldown pins (Note 3) Symbol VIH Min Typ Max 2.4 70% VDD Unit V V VIL 0.6 30% VDD VOH VOL Iin Iid VDD-0.5 0.5 10 -10 100 V V A A Note: 1. The test pins are as follows: TESTI1, TESTI2, TESTI3, TESTI4 2. The pulldown pins are not included. 3. The pulldown pins are as follows (Typ 50 k): TESTI1, TESTI2, TESTI3, TESTI4, SDINA, SDIND1, SDIND2, SDIN1, SDIN2, OPCL, CS, JX, SI, CTRL0, CTRL1 Note: Regarding the input/output levels in the text, the low level is represented as "L" or 0, and the high level as "H" or 1. In principle, "0" and "1" are used for the bus (serial/parallel), such as registers. (3) Current consumption (AVDD = AVB, DVB, DVDD = 5.0 V5%, Ta = 25C; master clock (XTI) = 22.5792MHz = 512 fs [fs = 44.1kHz]; when operating for DAC 4 channel with 1 kHz sinusoidal wave full-scale input to each of ADC 2 ch analog input pins) Power supply Parameter Power supply current 1) During operation a) AVDD + AVB + DVB b) DVDD (Note 1) c) Total (a+b) 2) When INIT RESET= "L"(reference value) Note 2 Power consumption 1) During operation a) AVDD+AVB+DVB b) DVDD (Note 1) c) Total(a+b) 2) When INIT RESET ="L" (reference value) Note 2 Min Typ 41 87 128 7 205 435 640 Max 162 850 Unit mA mA mA mA mW mW mW mW 35 Note: 1. Varies slightly according to the frequency used and contents of the DSP program. Note: 2. This is a reference value in case of using the crystal oscillator. But, varies slightly according to the types of crystal oscillators. M0018-E-00 - 12 - `98/07 [ASAHI KASEI] [AK7714] (4) Digital filter characteristics Values described below are design values cited as references. These are not for guaranteeing the characteristics. 1) ADC Section: (Ta = 25C; AVDD, DVDD, AVB, DVB = 5.0 V 5%; fs = 44.1 kHz) Parameter Pass band (-0.02 dB) (-6.0 dB) Stop band (Note 1) Pass band ripple (Note 2) Stop band attenuation (Notes 3,4) Group delay distortion Group delay (Ts = 1/fs) Note: 1. 2. 3. 4. Symbol PB SB PR SA GD GD Min 0 0 24.35 Typ Max 20.00 22.05 0.005 80 0 29.3 Unit kHz kHz kHz dB dB s Ts These frequencies scale with the sampling frequency (fs). The pass band is from DC to 19.75 kHz when fs = 44.1 kHz. The stop band is from 27.56 kHz to 2.795 MHz when fs = 44.1 kHz. When fs = 44.1 kHz, the analog modulator samples analog input at 2.8224 MHz. The input signal is not attenuate dBy the digital filter in the multiple bands (n x 2.8224 MHz 20.21 kHz ; n = 0, 1, 2, 3...) of the sampling frequency. 2) DAC section (Ta = 25C; AVDD, DVDD, AVB, DVB = 5.0 V 5%; fs = 44.1 kHz) Parameter Digital filter Pass band 0.07 dB (Note 1) (-6.0 dB) Stop band (Note 1) Pass band ripple Stop band attenuation Group delay (Ts = 1/fs ) (Note 2) Digital filter + Analog filter Amplitude characteristics 0 to 20.0 kHz Symbol Min Typ Max Unit PB 0 24.1 22.05 20.0 - 15.3 kHz kHz kHz dB dB Ts 0.5 dB SB PR SA GD 0.07 47 - Note: 1. The pass band and stop band frequencies are proportional to "fs" (system sampling rate), and are represente PB = 0.4535 fs(@ -0.06 dB) and SB = 0.546 fs, respectively. 2. The caluculating delay time which occurred by digital filtering. This time is from setting the 20-bit data of both channels on input register to the output of analog signal. M0018-E-00 - 13 - `98/07 [ASAHI KASEI] [AK7714] (5) Switching characteristics 1) System clock (AVDD = AVB, DVB, DVDD = 5.0 V5%, Ta = 25C, CL = 20 pF) Parameter Symbol Min Master clock (XTI) a) With a crystal oscillator: 256 fs: Frequency fMCLK 11.0 384 fs: Frequency fMCLK 12.288 512 fs: Frequency fMCLK 16.384 b)With an external clock input: 40 Duty factor ( 18.432 MHz) 45 ( > 18.432MHz ) 256 fs: Frequency fMCLK 11.0 : High level width tMCLKH 30 : Low level width tMCLKL 30 384 fs: Frequency fMCLK 12.288 : High level width tMCLKH 20 : Low level width tMCLKL 20 512 fs: Frequency fMCLK 16.384 : High level width tMCLKH 17 : Low level width tMCLKL 17 Clock rise time tCR Clock fall time tCF LRCLK Sampling frequency fs 32 Slave mode: Clock rise time Slave mode: Clock fall time BITCLK Slave mode: High level width Slave mode: Low level width Slave mode: Clock rise time Slave mode: Clock fall time tLR tLF fBCLK tBCLKH tBCLKL tBR tBF Typ Max 11.2896 16.9344 22.5792 12.288 18.432 22.5792 MHz MHz MHz 50 50 11.2896 60 55 12.288 % MHz 16.9344 18.432 MHz 22.5792 22.5792 MHz 6 6 48 ns ns kHz fs ns ns fs 44.1 1 10 10 48 100 100 64 6 6 Unit ns ns 2) Reset (AVDD = AVB, DVB, DVDD = 5.0 V 5%, Ta = 25C, CL = 20 pF) Parameter Symbol Min INIT RESET (Note 1) tRST DSP RESET (Note 1) tRST CODEC RESET (Note 1) tRST Note 1. "L" is acceptable when power is turned on. M0018-E-00 150 150 150 - 14 - Typ Max Unit ns ns ns `98/07 [ASAHI KASEI] [AK7714] 3) Audio interface (AVDD = AVB, DVB, DVDD = 5.0 V 5%,Ta = 25C, CL = 20 pF) Parameter Symbol Min Slave mode BITCLK frequency fBCLK 48 BITCLK low level width tBCLKL 100 BITCLK high level width tBCLKH 100 tBLRD 40 Delay time from BITCLK"" to LRCLK tLRBD 40 Delay time from LRCLK to BITCLK "" Delay time from LRCLK to serial data output tLRD Delay time from BITCLK to serial data output tBSOD Serial data input latch hold time tBSIDS 40 Serial data input latch setup time tBSIDH 40 Master mode BITCLK frequency fBCLK BITCLK duty factor tBLRD 40 Delay time from BITCLK"" to LRCLK tLRBD 40 Delay time from LRCLK to BITCLK"" Delay time from LRCLK to serial data output tLRD Delay time from BITCLK to serial data output tBSOD Serial data input latch hold time tBSIDS 40 Serial data input latch setup time tBSIDH 40 M0018-E-00 - 15 - Typ Max 64 70 70 64 50 Unit fs ns ns ns ns ns ns ns ns fs 70 70 ns ns ns ns ns ns `98/07 [ASAHI KASEI] [AK7714] 4) Microcomputer interface (AVDD = AVB, DVB, DVDD = 5.0 V 5%, Ta = 25C, CL = 20 pF) Parameter Symbol Min Microcomputer interface signal CS Fall time tCSF CS Rise time tCSR Rest time until RDY and SO Hi-Z states tCSHR from CS"" Set time until RDY and SO Hi-Z states tCSHS from CS"" WRQ fall time tWRF WRQ rise time tWRR SCLK fall time tSF SCLK rise time tSR SCLK low level width tSCLKL 150 SCLK high level width tSCLKH 150 Microcomputer to AK7714 tREW 200 Time from RESET"" to WRQ"" tWRE 200 Time from WRQ"" to RESET"" WRQ high level width tWRQH 200 tWSC 200 Time from WRQ "" to SCLK"" tSCW Time from SCLK"" to WRQ"" 6xtMCLK SI latch setup time tSIS 100 SI latch hold time tSIH 100 AK7714 to microcomputer CS high level width tCSH 200 tSCS Time from SCLK"" to CS"V" 6xtMCLK tCSC 200 Time from CS"" to SCLK"" tCSDR Time from CS"" to DRDY"" tSOS Delay time from SCLK "" to SO output AK7714 to microcomputer (RAM DATA read-out) SI latch setup time (SI="H") tRSISH 100 SI latch setup time (SI="L") tRSISL 100 SI latch hold time tRSIH 100 tSOPD Time from SCLK "" to SO (PRAM) Time from SCLK "" to SO (CRAM, OFRAM) tSOCOD M0018-E-00 - 16 - Typ Max Unit 10 10 100 ns ns ns 200 10 10 10 10 ns ns ns ns ns ns ns ns ns ns ns ns ns ns 100 100 ns ns ns ns ns 100 100 ns ns ns ns ns `98/07 [ASAHI KASEI] [AK7714] (6) Timing Diagram 1) System clock 2) Reset signal M0018-E-00 - 17 - `98/07 [ASAHI KASEI] [AK7714] 3) Audio interface 4) Microcomputer interface Microcomputer interface signals M0018-E-00 - 18 - `98/07 [ASAHI KASEI] [AK7714] Microcomputer to AK7714 Note : Timing for RUN state is the same except that RESET is set to "H" RESET represents system reset in normal use. AK7714 to Microcomputer M0018-E-00 - 19 - `98/07 [ASAHI KASEI] [AK7714] AK7714 to Microcomputer (RAM data read-out) M0018-E-00 - 20 - `98/07 [ASAHI KASEI] [AK7714] Function Description (1) Various settings 1) OPCL (pin 34): ADC and DAC connection selector pin (See Block Diagram on page 2.) Normally, OPCL is used in "L" or open. (Internal connection mode) In this case, ADC output and DAC1/DAC2 inputs are directly connected to the DSP internally. At this time, leave the SDINA (pin 12), SDIND1 (pin 17) and SDIND2 (pin 18) open or set to "L". It should be noted that "L" is output from the SDOUTA (pin 14), SDOUTD1 (pin 15) and SDOUTD2 (pin 20). When the OPCL is set to "H", the ADC output and DAC1/DAC2 inputs can be used independently from the DSP. (Input/output formats are restricted.) 2 Note: SDINA supports only MSB-first 24-bit input (including I S compatibility). 2 SDOUTA supports only MSB-first 20-bit output (including I S compatibility). 2 SDIND1 and SDIND2 support only MSB-first 20-bit inputs (including I S compatibility). 2) CTRL1 (pin 62) and CTRL0 (pin 56): clock output control pins CLKO output and LRCLK and BITCLK outputs in the master mode can be fixed to "L" or "H" by setting these two pins. Mode CTRL1 0 0 1 1 1 2 3 4 CTRL0 0 1 0 1 Master mode Master mode CLKO LRCLK BITCLK Output Output Output Disabled (This is a test mode, so do not use it.) "L" Output Output "L" "H" (For "L", see Note.) "L" Note: When CTRL1 and CTRL0 are used in the open state, Mode 1 will be selected. 2 Output is set to "L" when I S compatible. Mode 4 can be used only when the AK7714 is used "Analog to Analog". 3) CKS1 (pin 64) and CKS0 (pin 63): Clock selector pin CKS1 0 0 1 1 CKS0 0 1 0 1 XTI DSP 384fs 384fs 512fs 512fs 256fs 256fs Test mode (disabled) fs: Sampling frequency 4) SMODE (pin 65): Slave and master mode selector pin Sets LRCLK (pin 36) and BITCLK (pin 37) to either input or output. a) Slave mode: SMODE = "L" LRCLK (1 fs) and BITCLK (48 fs or 64 fs) become input. b) Master mode: SMODE = "H" LRCLK (1 fs) and BITCLK (64 fs) become output. M0018-E-00 - 21 - `98/07 [ASAHI KASEI] [AK7714] 5) Control registers The control registers (16 bits) can be set via the microcomputer interface in addition to the control pins. For the value to be written in the control registers, see the description of the microcomputer interface. The following describes the control register map. Control register map ( indicates the default values.) Code Function C15 Selects the data reset function after reset is released. C14 Selects delay RAM sampling 0: 1Sampling 1: 2 Sampling C13 Selects DRAM addressing method 0: Ring addressing 1: Linear addressing C12 Random number generator circuit 0: Unused 1: Used C11 Test mode (Use at 0) 0: Normal operation 1: Test mode C10 Test mode (Use at 0) 0: Normal operation 1: Test mode C9 Test mode (Use at 0) 0: Normal operation 1: Test mode C8 Resets ADC section 0: Normal operation 1: Reset C7 Sets internal path 0: ADC serial data selected 1: SDIN1 selected C6 Sets internal path 0: Normal setting 1: Sets the path selected by C7 C5 DAC2 section reset control 0: Normal operation 1: DAC2 section reset C4 DAC1 section reset control 0: Normal operation 1: DAC1 section reset C3 SDOUT output enable 0: SDOUT = Output 1: SDOUT = "L" C2 C1 Selects SDIN1 and SDIN2 input mode. Mode C2 C1 1 0 0 MSB first (24 bits) 2 0 1 LSB first (24 bits) 3 1 0 LSB first (20 bits) 4 1 1 LSB first (16 bit) 2 Note: When CO = 1, the state is I S compatible independent of mode setting; however, set to Mode 1. 2 Select I S compatible. C0 0: Used 1: Unused 0: Normal setting 2 2 1: I S compatible (In this case, all input/output pins are I S compatible.) Data can be loaded into the control registers only when DSP RESET = "L" and CODEC RESET = "L". If used otherwise, an operation error will occur. To avoid an operation error, do not use it. M0018-E-00 - 22 - `98/07 [ASAHI KASEI] [AK7714] a) C0, C1, C2 See (5) Audio data interface (internal connection mode ) b) C3 In case of not using the SDOUT, if this code is set "1" then the SDOUT outputs "L" level. c) C4 In case of using only DAC2, this code can set to "1" and DAC1 will RESET. It can useful for saving the power consumption of DAC1. The output signals of AOUTL1 and AOUTR1 will be Hi-z. d) C5 In case of using only DAC2, this code can set to "1" and DAC1 will RESET. It can useful for saving the power consumption of DAC1. The output signals of AOUTL1 and AOUTR1 will be Hi-z. e) C6, C7 Normally C6 and C7 are "0" setting. In detail, please see (8) Special use, 2) Use as ADC and DAC (mainly for test ). f) C8 In case of not using the ADC part, this code can RESET the ADC part. In this case, the digital output from ADC will be "00000h" and it will save the power consumption of the ADC part. g) C9, C10, C11 This is test mode. C9, C10 and C11 should be "0". h) C12 This DSP has a single feedback type shift-register [24,21,19,18,17,16,15,14,14,19,9,5,1]s independently from calculation block. This register change the data in every sampling time. And its output connected with DBUS, so in case of selected MSRG command at program code, then 24-bit random data will appear in every sampling . In case of using this register, please set this code to "1". i) C13 This code sets the addressing method of DRAM ( Data Ram ). C13 = 0 : Ring addressing C13 = 1 : Linear addressing. DRAM has 128-word x 24-bit and has 2 addressing pointers (DP0, DP1). The Ring addressing mode : Its start address increments 1 by every sampling time. The Linear addressing mode : Its start address is always same , DP0 = 00h and DP1 = 40h. j) C14 This code is setting for DLYRAM (internal 4k-word x 16-bit Delay RAM )sampling method. Normally C14 = 0, this means its address pointer will work as ring addressing by every sampling. If it set C14 = 1, this means the address pointer will work as ring addressing by every 2 sampling. This is a decimation mode and it can extend delay time. But, it will appear aliasing. When it is C14=1 mode, the Delay Ram area will consist 3 banks. The bank 1 is from 000h to 3FFh : ( The address of this area is always 1 sampling ring addressing. ) The bank 2 , bank 3 and bank 4 ( 400h to 7FFh, 8FFh to BFFh and C00h to FFFh ) can set to decimation mode. k) C15 Normally it should be C15=0. At this time after release the system reset, DRAM ( Data Ram ) and DLYRAM ( Internal delay Ram ) will be clear to "0" . It takes 8LRCLK at 512fs mode, 11LRCLK at 384fs mode and 16LRCLK at 256fs mode after the Reset pulse comes out. The Reset pulse comes out at first rising point of LRCLK at master mode and in case of slave mode, it comes out about after 3LRCLK. M0018-E-00 - 23 - `98/07 [ASAHI KASEI] [AK7714] (2) Power supply startup sequence Turn on the power by setting to INIT RESET = "L",DSP RESET = "L" and CODEC RESET = "L". Then the AK7714 is initialized by setting to INIT RESET = "H". Note 1) Initialization by INIT RESET is sufficient if it is done only when the power is turned on. Note1: Set to INIT RESET = "H" after setting the oscillation when a crystal oscillator is used. This setting time may differ depending on the crystal oscillator and its external circuit. 2: Do not stop the system clock (slave mode: XTI, LRCLK, BITCLK, master mode: XTI) except when INIT RESET = "L". If these clock signals are not supplied, too much current will flow because the dynamic logic is used internally, and an operation failure may result. AVDD, AVB, DVB DVDD INIT RESET DSP RESET CODEC RESET Power OFF When a crystal oscillator is used, ensure stable oscillation in this period. DSP RESET and CODEC RESET can be controlled simultaneously during normal use. Fig. Power supply startup sequence M0018-E-00 - 24 - `98/07 [ASAHI KASEI] [AK7714] (3) Resetting The AK7714 has three reset pins: INIT RESET,DSP RESET and CODEC RESET. The INIT RESET pin is used to initialize the AK7714, as shown in "Power supply startup sequence above." DSP RESET and CODEC RESET are normally controlled simultaneously. The system is reset when DSP RESET = "L" and CODEC RESET = "L". (Description of "reset" is for "system reset".) Under the condition of this system reset, the program write operation is performed (except for write operation during running). During the system reset phase, the ADC and DAC sections are also reset. (The digital section of ADC output is MSB first 00000h and the analog section of DAC output is Hi-z. ) CLKO is output even during the system reset phase if CTRL (1:0) = 0h (Mode 1), but LRCLK and BITCLK in the master mode will stop. The system reset is released by setting either DSP RESET or CODEC RESET to "H", and this will activate the internal counter. LRCLK and BITCLK in the master mode are generated by this counter: however, a hazard may occur when a clock signal is generated. When the system reset is released in the slave mode, internal timing will be actuated in synchronization with "" of LRCLK (when the standard input format is used). Timing between the external and internal clocks is adjusted at this time. If the phase difference in LRCLK and internal timing is within about -1/16 to 1/16 of the input sampling cycle (1/fs) during the operation, the operation is performed with internal timing remaining unchanged. If the phase difference exceeds the above range, the phase is adjusted by synchronization with "" of LRCLK (when the standard input format is used). This is a circuit to prevent failure of synchronization with the external circuit owing to noise and the like. For some time after returning to the normal state after loss of synchronization, normal data will not be output. If you want to change the clock, do so while the system is reset. The ADC section can output 516-LRCLK after its internal counter started. (The internal counter starts at the first rising edge of LRCLK at master mode. In case of slave mode, it starts end of 2LRCLK after release of system reset. ) The AK7714 performs normal operation when both DSP RESET and CODEC RESET are set to "H". (4) System clock The required system clock is XTI (256 fs/384 fs/512 fs), LRCLK (fs) and BITCLK (64 fs) in the slave mode, and is XTI (256 fs/384 fs/512 fs) in the master mode. LRCLK corresponds to the standard digital audio rate (32 kHz, 44.1 kHz, 48 kHz). fs XTI (Master clock) BITCLK 256 fs 384 fs 512 fs 64 fs 32.0 kHz - Note 12.2880 MHz 16.3840 MHz 2.0480 MHz 44.1 kHz 11.2896 MHz 16.9344 MHz 22.5792 MHz 2.8224 MHz 48.0 kHz 12.2880 MHz 18.4320 MHz - Note 3.0720 MHz Note: 256 fs is not supported at fs = 32.0 kHz. 512fs is not supported at fs = 48.0 kHz. SMODE L L L H H H M0018-E-00 CKS1 L L H L L H CKS0 L H L L H L XTI 384 fs 512 fs 256 fs 384 fs 512 fs 256 fs LRCLK, BITCLK Input Input Input Output Output Output - 25 - `98/07 [ASAHI KASEI] [AK7714] 1) Master clock (XTI pin) The master clock is obtained by connecting a crystal oscillator between the XTI pin and XTO pin or by inputting an external clock into the XTI pin while the XTO pin is open. CLKO outputs a clock having the same frequency as the XTI. (The phase is different. Also, the phase difference varies slightly according to the product. When a crystal oscillator is used, the same frequency is obtained after the oscillation of the crystal oscillator has settled.) In the AK7714, CLKO will be output when power is turned on and oscillation has occurred. If CLKO is not required, set to CTRL1 = "H". 2) Slave mode The required system clock is XTI (256 fs/384 fs/512 fs), LRCLK (1 fs) and BITCLK (48/64 fs). The master clock (XTI) and LRCLK must be synchronized, but the phase does not have to be adjusted. 3) Master mode The required system clock is XTI (256 fs/384 fs/512 fs). When the master clock (XTI) is input, LRCLK (1 fs) and BITCLK (64 fs) will be output from the internal counter synchronized with the XTI. (CTRL0 = "L" during normal operation.) LRCLK and BITCLK will not be output during initial reset (INIT RESET = "L") and system reset (DSP RESET = CODEC RESET = "L"). M0018-E-00 - 26 - `98/07 [ASAHI KASEI] [AK7714] (5) Audio data interface (internal connection mode ) The serial audio data pins SDIN1, SDIN2 and SDOUT (OPCL = L: Internal connection mode) are interfaced with the external system, using LRCLK and BITCLK. The data format is the first MSB of the 2's complement. Normally, the input/output format, in addition to the standard format used by AKM, can be changed to the I 2S compatible mode by setting the control register C0 to 1. (In this case, all input/output audio data pin interface is in the I2S compatible mode.) The input SDIN1 and SDIN2 formats are adjusted (24 bits) at initialization. Setting the control registers C2 and C1 will cause them to be compatible with 24 bits, 20 bits and 16 bits. (Note: C0 = 0) However, inidividul setting of SDIN1 and SDIN2 is not allowed. The output SDOUT is fixed at 24 bits. At slave mode BITCLK corresponds to not only 64fs but also 48fs. But, we recommend 64fs. Following formats describe 64fs examples. 1) Standard input format (C0 = 0: initial set value) a) Mode 1 (C2, C1 = 0, 0: Initial set value) * When you want to input the MSB-first 20-bit data into SDIN1 and 2, input four "0s" following the LSB. b) Mode 2, Mode 3 and Mode 4 SDIN1, 2 Mode 4 SDIN1 and 2 Mode 2: (C2, C1) = (0, 1) 24 bits SDIN1 and 2 Mode 3: (C2, C1) = (1, 0) 20 bits SDIN1 and 2 Mode 4: (C2, C1) = (1, 1) 16 bits M0018-E-00 - 27 - `98/07 [ASAHI KASEI] [AK7714] 2) I2S compatible input format (C0 = 1) Mode 1: (C2, C1) = (0, 0) must be set. 3) Standard output format (C0 = 0: initial set value) 4) I2S compatible output format (C0 = 1) M0018-E-00 - 28 - `98/07 [ASAHI KASEI] [AK7714] (6) Interface with microcomputer Interface with the microcomputer is provided by 7 control signals: CS (Chip Select Bar), WRQ (Write ReQuest Bar), SCLK (Serial data input CLocK), SI (Serial data Input), SO (Serial data Output), RDY (ReaDY) and DRDY (Data ReaDY). In the AK7714, two types of operations are provided; writing and reading during the reset phase (namely, system reset) and those during the run phase. During the reset phase, data can be written to the control register, program RAM,coefficient RAM, offset RAM, and external conditional jump code, and data can be read from the program RAM,coefficient RAM and offset RAM. During the run phase, data can be written to the coefficient RAM,offset RAM and external conditional jump code, and data on the DBUS (data bus) can be read from SO. CS is used also for SO control in addition to the chip selection. When only one AK7714 is used without SO, CS = "L" is allowed at all times. If there is no communication with the microcomputer, set SCLK to "H" and SI to "L" for use. Data is serially input and output with the MSB first. The following 8-bit command data is sent first, and the specified work is performed. Command code list Contents of command Conditions for use: Program RAM write [RSPW] External conditional JMP code write [JCON] Coefficient RAM write [RSCW] Coefficient RAM write [RNCW] Offset RAM write [RSOW] Offset RAM write [RNOW] CRAM/OFFRAM rewrite preparation[BNBW] Control register write [CONW] Program RAM read Program CRAM read Program OFRAM read Code (C7C6C5C4C3C2C1C0) During reset phase: both reset and run phases: during reset phase: during run phase: during reset phase: during run phase: during run phase: during reset phase: during reset phase: during reset phase: during reset phase: Code (11000000) Code (11000100) Code (10100000) Code (10100100) Code (10010000) Code (10010100) Code (10001000) Code (00000110) Code (11000011) Code (10100001) Code (10010001) NOTE: Do not send codes other than the above command codes. Otherwise, an operation error may occur. M0018-E-00 - 29 - `98/07 [ASAHI KASEI] [AK7714] 1) Write during reset phase a) Control register write (during reset phase) Data comprising a set of three bytes is used to perform the control register write operation (during the reset phase). When all data has been transferred, the RDY terminal goes to "L". It goes to "H" upon completion of the write operation. Data transfer procedure 1 Command code { 2 Control data { 3 Control data { (00000110) (C15.....C8) (C7 .....C0) The register to control the operation mode of this LSI comprises 16 bits. For the function of each bit, see the description of 5) "Control registers" on page 22. Control register write operation M0018-E-00 - 30 - `98/07 [ASAHI KASEI] [AK7714] b) Program RAM write (during reset phase) The program RAM write operation is performed during the reset phase according to data comprising a set of 7 bytes (in case of 1-word program RAM writting). When all data has been transferred, the RDY terminal is set to "L". Upon completion of writing into PRAM, it goes to "H" to allow the next data to be input. When data of continuous addresses is 4 to { 7 ) of after the next address as is. (No command code or address is required and RESET written, input the data({ and WRQ hold to "L".) To write discontinuous data, shift the WRQ terminal from "H" to "L" again. Then input the command code, address and data in that order. (For RESET, operate both CODEC RESET and DSP RESET simultaneously.) Data transfer procedure 1 Command code { 2 Address upper { 3 Address lower { 4 Data { 5 Data { 6 Data { 7 Data { (11000000) (0000000A8) (A7......A0) (D15 .....D8) (D23 .....D16) (D15 .....D8)) (D7......D0) Input of continuous address data into PRAM Input of discontinuous address data into PRAM M0018-E-00 - 31 - `98/07 [ASAHI KASEI] [AK7714] c) Coefficient RAM write (during reset phase) Data comprising a set of 5 bytes (in case of 1-word CRAM writting ) is used to perform the coefficient RAM write operation (during the reset phase). When all data has been transferred, the RDY terminal goes to "L". Upon completion of writing into CRAM, it goes to "H" to allow the next data to be input. When data of continuous addresses is written, 4 to { 5 ) of after the next address as is. (No command code or address is required and RESET and input the data({ WRQ hold to "L".) To write discontinuous data, shift the WRQ terminal from "H" to "L". Then input the command code, address and data in that order. (For RESET, operate both CODEC RESET and DSP RESET simultaneously.) Data transfer procedure 1 Command code { 2 Address upper { 3 Address lower { 4 Data { 5 Data { (10100000) (0000000A8) (A7......A0) (D15 ..... D8) (D7......D0) Input of continuous address data into CRAM Input of discontinuous address data into CRAM M0018-E-00 - 32 - `98/07 [ASAHI KASEI] [AK7714] d) Offset RAM write (during reset phase) Data comprising a set of 3 bytes ( in case of 1-word Offset RAM writting ) is used to perform offset RAM write operation (during the reset phase). In this case the operation must be started from address 0. When data of continuous 2 to { 3 ) of after the next address as is. (No command code is required and addresses is written, input the data({ RESET and WRQ hold to "L".) When all data has been transferred, the RDY terminal goes to "L". Upon completion of writing into the OFFRAM, it goes to "H" to allow the next data to be input. (For RESET, operate both CODEC RESET and DSP RESET simultaneously.) Data transfer procedure 1 Command code { 2 Data { 3 Data { (10010000) (0000 D11 D10 D9 D8) (D7......D0) Input of data into OFFRAM M0018-E-00 - 33 - `98/07 [ASAHI KASEI] [AK7714] e) External conditional jump code write (during reset phase) Data comprising a set of two bytes is used to perform the external conditional jump code write operation. The data can be input during both the reset and operation phases, and the input data is set to the specified register at the leading edge of LRCLK. When all data has been transferred, the RDY terminal goes to "L". Upon completion of writing, it goes to "H". A jump command will be executed if there is any one agreement between "1" of each bit of the external condition code 8 bits (soft set) plus 1 bit (hard set) at the external input terminal JX and "1" of each bit of the IFCON field. The data during the reset phase can be written only before release of the reset, after all data has been transferred. WRQ transition from "L" to "H" in the write operation during the reset phase must be executed after three LRCLK in the slave mode and one LRCLK in master mode, respectively, from the falling edge of LRCLK after release of the reset. Then RDY goes to "H" after capturing the rise of the next LRCLK. Write operation from the microcomputer is disabled until RDY goes to "H". The IFCON field provides external conditions written on the program. Note: The LRCLK phase is inverted in the I2S-compatible state. 7 0JX Check if there is any one agreement between the bit specified in IFCON and "1" in the external condition code. 16 8 IFCON field Data transfer procedure 1 Command code (11000100) { 2 Code data (D7......D0) { External condition code Timing for external conditional jump write operation (during reset phase) M0018-E-00 - 34 - `98/07 [ASAHI KASEI] [AK7714] 2) Read during reset phase a) Program RAM read (during reset phase) To read data written into PRAM, input the command code and the address you want to read out. After that, set SI to "H" and SCLK to "L". Then the data is output from SO in synchronization with the falling edge of SCLK. (Ignore the RDY operation that will occur in this case.) If there are continuous addresses to be read, repeat the above procedure starting from the step where SI is set to "H". Data transfer procedure 1 Command code input { 2 Read address input { (11000011) (0......A8) (A7......A0) Reading of PRAM data M0018-E-00 - 35 - `98/07 [ASAHI KASEI] [AK7714] b) CRAM data read (during reset phase) To read out the written coefficient data, input the command code and the address you want to read out. After that, set SI to "H" and SCLK to "L" as preparation. Then, when SI is set to "L", the data is output from SO in synchronization with the falling edge of SCLK. If there are continuous addresses to be read, repeat the above procedure starting from the step where SI is set to "H". Data transfer procedure 1 Command code { 2 Address { (10100001) (0......A8) (A7......A0) Reading of CRAM data M0018-E-00 - 36 - `98/07 [ASAHI KASEI] [AK7714] c) OFRAM data read (during reset phase) The written offset data can be read out during the reset phase. To read it, input the command code and 8-bit "0". After that, set SI to "H" and SCLK to "L". This completes preparation for outputting the data. Then set SI to "L", and the data is output in synchronization with the falling edge of SCLK. In this case, OFRAM can be output only from the address data at address 0. Data transfer procedure 1 Command code { 2 Data input { (10010001) (00000000) Reading of OFRAM data M0018-E-00 - 37 - `98/07 [ASAHI KASEI] [AK7714] 3) Write during RUN phase a) CRAM/OFRAM rewrite preparation and write (during RUN phase) This function is used to rewrite CRAM (coefficient RAM) and OFRAM (offset RAM) during program execution. After inputting the command code, you can input a maximum of 16 data of the continuous addresses you want to rewrite. Then input the write command code and rewrite the leading address. Every time the RAM address to be rewritten is specified, the contents of RAM are rewritten. The following is an example to show how five data from address "10" of the coefficient RAM are rewritten: Coefficient RAM execution address 7 8 9 10 11 13 16 11 12 13 14 15 { { { { { Rewrite position Note that address "13" is not executed until address "12" is rewritten. Data transfer procedure 1 Command code (10001000) *Preparation for rewrite { 2 Data (D15 .....D8) { 3 Data (D7......D0) { 1 Command code *Rewrite 1) CRAM (10100100) { 2 Address upper (0000000A8) { 3 Address lower (A7000...A0) { 1 Command code 2) OFRAM (10010100) { 2 Address upper (00000000) { 3 Address lower (000A4...A0) { Note: CRAM ranges from A8 to A0. OFRAM ranges from A4 to A0. Note: The RDY signal will go to high within the maximum of two LRCLKs if the RDYLG width is programmed to ensure a new address to be rewritten within one sampling cycle. CRAM and OFRAM rewriting preparation and writing M0018-E-00 - 38 - `98/07 [ASAHI KASEI] [AK7714] b) External conditional jump code rewrite (during RUN phase) Data comprising a set of two bytes is used to write the external conditional jump code. Data can be input during both the reset and operation phases, and input data is set to the specified register at the rising edge of LRCLK. When all data has been transferred, the RDY terminal goes to "L". Upon completion of writing, it goes to "H". A jump command will be executed if there is any one agreement between each bit of the 8-bit external condition code and "1"of each bit of the IFCON field. A write operation from the microcomputer is disabled until RDY goes to "H". Note: The LRCLK phase is inverted in the I2S-compatible state. Data transfer procedure 1 Command code { 2 Code .data { (11000100) (D7......D0) External condition jump write timing (during RUN phase) M0018-E-00 - 39 - `98/07 [ASAHI KASEI] [AK7714] 4) Read-out during RUN phase (SO output ) SO outputs data on DBUS (data bus) of the DSP section. Data is set when @MICR is specified by the DST field. Setting of data allows DRDY to go to "H", and data is output synchronized with the falling edge of SCLK. When CS goes to "H", DRDY goes to "L" to wait for the next command. Once DRDY goes to "H", the data of the last @MICR command immediately before DRDY goes to "H" will be held until CS goes to "H", and subsequent commands will be rejected. A maximum of 24 bits are output from SO. After the required number of data (not exceeding 24 bits) is taken out by SCLK, the next data can be output by setting CS to "H". SO read (during RUN phase) (7) ADC section high-pass filter The AK7714 incorporates a digital high-pass filter (HPF) for cancelling the section DC offset in the ADC section. The HPF cut-off frequency is about 1 Hz (fs = 48 kHz). This cut-off frequency is proportional to the sampling frequency (fs). Cut-off frequency M0018-E-00 48 kHz 0.93 Hz 44.1 kHz 0.86 Hz - 40 - 32 kHz 0.62 Hz `98/07 [ASAHI KASEI] [AK7714] (8) Special use 1) External connection mode Normally, OPCL is used at "L" (internal connection mode), but when OPCL is set to "H", the ADC output and DAC1/DAC2 inputs can be used independently form DSP. (External connection mode) OPCL = "H": External connection mode The following shows the input/output interface in external connection mode: 2 * SDINA for MSB-first 24-bit input (including I S compatibility) 2 * SDOUTA for MSB-first 20-bit output (including I S compatibility) 2 * SDOUTD1 and SDOUTD2 for MSB-first 24-bit outputs (including I S compatibility) 2 * SDIND1 and SDIND2 for MSB-first 20-bit inputs (including I S compatibility) 2 Conversion between the input/output standard format and I S is interlocked with the control register C0, similar to the case for internal connection mode. M0018-E-00 - 41 - `98/07 [ASAHI KASEI] [AK7714] 2) Use as ADC and DAC (mainly for test) Only the ADC and DAC sections can be operated while keeping the DSP section in the reset state with the independent control of DSP RESET and CODEC RESET. (When no DSP processing is required, power saving and noise reduction can be expected. However, the ADC data cannot be output in internal connection mode. In external connection mode, it is output from SDOUTA.) In internal connection mode, setting of the control registers allows the following operations to be performed: a) ADC to DAC1 and DAC2 (Analog to Analog) The ADC output data is directly connected over to DAC1 and DAC2. (C6 = 1, C7 = 0) When input to the DAC2 is not required, set C5 = 1. (When input to the DAC1 is not required, set C4 = 1.) b) SDIN1 to DAC1 and DAC2 SDIN1 input data is directly connected to DAC1 and DAC2. (C6 = 1, C7 = 1) 2 In this case, only the MSB-first 20-bit input (including I S compatibility: C0 = 1) is supported. When input to DAC2 is not required, set C5 = 1. (When input to DAC1 is not required, set C4 = 1.) For this operation, set only CODEC RESET to "H" after setting the control registers during the system reset phase (DSP RESET = CODEC RESET = "L"). To make a new setting, be sure to perfom the system reset. M0018-E-00 - 42 - `98/07 [ASAHI KASEI] [AK7714] System Design (1) Example circuit M0018-E-00 - 43 - `98/07 [ASAHI KASEI] [AK7714] (2) Peripheral circuit 1) Ground and power supply To minimize digital noise coupling, AVDD and DVDD are individually decoupled in AK7714. System analog power is supplied to AVDD, AVB and DVB. AVB and DVB are connected to each other through the IC board, and eventually have several ohms of resistance. If the set of AVDD, AVB and DVB and DVDD are driven by individual power sources, start up AVDD, AVB and DVB simultaneously with DVDD, or start up AVDD, AVB and DVB first. Generally, power supply and ground wires must be connected separately according to the analog and digital systems. Connect them at a position close to the power source on the PC board. Decoupling capacitors, and ceramic capacitors of small capacity in particular, should be connected at positions as close as possible to the AK7714. If the absolute maximum rating conditions of a power supply cannot be maintained depending on the system, it is recommended to supply the AK7714 power from the same regulator. Power patterns must be separated into analog and digital patterns. For a digital pattern, connection must be made through an appropriate one-ohm resistor from the regulator. In this case, the capacitor with the larger capacity must be connected to the analog side. 2) Reference voltage The input voltage difference between the VRADH pin and the VRADL pin determines the full scale of analog input, while the potentials difference between the VRDAH pin and the VRDAL pin determines the full scale of the analog output. Normally, connect AVDD to VRADH and VRDAH, and connect 0.1F ceramic capacitors from them to AVSS. VCOM is used as the common voltage of the analog signal. To shut out high frequency noise, connect a 0.1F ceramic capacitor in parallel with an appropriate 10F electrolytic capacitor between this pin and AVSS. The ceramic capacitor in particular should be connected at a position as close as possible to the pin. Do not lead current from the VCOM pin. To avoid coupling to the AK7714, digital signals and clock signals in particular should be kept away from the VRADH, VRADL, VRDAH, VRDAL and VCOM pins as far as possible. 3) Analog input Analog input signals are applied to the modulator through the differential input pins of each channel. The input voltage is equal to the differential voltage between AIN+ and AIN- (VAIN = (AIN+) - (AIN-)), and the input range is FS = (VRADH - VRADL) x 0.4. When VRADH = 5V and VRADL = 0V, the input range is within 2.0 V. The output code format is given in terms of 2's complements. Table 1 shows the output code relative to input voltage. Input voltage > (+FS - 1.5 LSB) Output code (hexadecimal) 20 bit 3FFFF -0.5 LSB 00000 7FFFF > (-FS + 0.5 LSB) 80000 Table 1. Output code relative to input voltage When fs = 48 kHz, the AK7714 samples the analog input at 3.072 MHz. The digital filter eliminates noise from 30 kHz to 3.042 MHz. However, noise is not rejected in the bandwidth close to 3.072 MHz. Most audio signals do not have large noise in the vicinity of 3.072 MHz, so a simple RC filter is sufficient. A/D converter reference voltage is applied to the VRADH and VRADL pins. Normally, connect AVDD to VRADH, and AVSS to VRADL. To eliminate high frequency noise, connect a 0.1 F ceramic capacitor in parallel with a 10F electrolytic capacitor between the VRADH pin and VRADL. M0018-E-00 - 44 - `98/07 [ASAHI KASEI] [AK7714] The analog source voltage to the AK7714 is +5 V. Voltage of AVDD + 0.3 V or more, voltage of AVSS - 0.3 V or less, and current of 10 mA or more must not be applied to analog input pins (AINL and AINR). Excessive current will damage the internal protection circuit and will cause latch-up, thereby damaging the IC. Accordingly, if the surrounding analog circuit voltage is 15 V, the analog input pins must be protected from signals with the absolute maximum rating or more. Fig. 1 Example of input buffer circuit (differential input) Fig. 2 Example of input buffer circuit (single end input) An analog signal can be applied to the AK7714 is single end mode. In this case, apply the analog signal (the full scale is 4.0 Vpp when the internal reference voltage is used) to the AIN-input, and bias to the AIN+input. However, use of a low saturated operational amplifier is recommended if the operational amplifier is driven by the 5-volt power supply. The electrolytic capacitor connected to AIN+ is effective for reducing the second harmomics. (See Fig. 2.) 4) Analog output Analog output is single-ended, and the output range is 2.95Vpp (typical) with respect to VCOM voltage. The out-ofband noise (shaping noise) produced by the built-in modulator is reduced by the built-in switched capacitor filter (SCF) and continuous filter (CTF). Therefore, it is not necessary to add an external filter for normal application. The input code format is given in terms of 2's complements with the positive full-scale output for the 3FFFFH(@ 20 bit) input code, and the negative full-scale output for the 80000H (@ 20 bit) input code. VCOM voltage is output as an ideal value for 00000H(@ 20 bit) input code. 5) Connection to digital circuit To minimize the noise resulting from the digital circuit, connect CMOS logic to the digital output. The applicable logic family includes the 4000B, 74HC, 74AC, 74ACT and 74HCT series. M0018-E-00 - 45 - `98/07 [ASAHI KASEI] [AK7714] Package z 100-pin LQFP (Unit : mm) z Material & Lead finish Package: Lead-frame: Lead-finish: M0018-E-00 Epoxy Copper Soldering plate - 46 - `98/07 [ASAHI KASEI] [AK7714] Marking Meanings of XXXXAAA XXXX: Time of manufacture (numeral) AAA: Lot number (Alphabet) M0018-E-00 - 47 - `98/07 IMPORTANT NOTICE zThese products and their specifications are subject to change without notice. Before considering any use or application, consult the Asahi Kasei Microsystems Co., Ltd. (AKM) sales office or authorized distributor concerning their current status. zAKM assumes no liability for infringement of any patent, intellectual property, or other right in the application or use of any information contained herein. zAny export of these products, or devices or systems containing them, may require an export license or other official approval under the law and regulations of the country of export pertaining to customs and tariffs, currency exchange, or strategic materials. zAKM products are neither intended nor authorized for use as critical components in any safety, life support, or other hazard related device or system, and AKM assumes no responsibility relating to any such use, except with the express written consent of the Representative Director of AKM. As used here: (a) A hazard related device or system is one designed or intended for life support or maintenance of safety or for applications in medicine, aerospace, nuclear energy, or other fields, in which its failure to function or perform may reasonably be expected to result in loss of life or in significant injury or damage to person or property. (b) A critical component is one whose failure to function or perform may reasonably be expected to result, whether directly or indirectly, in the loss of the safety or effectiveness of the device or system containing it, and which must therefore meet very high standards of performance and reliability. zIt is the responsibility of the buyer or distributor of an AKM product who distributes, disposes of, or otherwise places the product with a third party to notify that party in advance of the above content and conditions, and the buyer or distributor agrees to assume any and all responsibility and liability for and hold AKM harmless from any and all claims arising from the use of said product in the absence of such notification.