EVAL-AD1954EB Analog Devices Inc, EVAL-AD1954EB Datasheet
EVAL-AD1954EB
Specifications of EVAL-AD1954EB
Related parts for EVAL-AD1954EB
EVAL-AD1954EB Summary of contents
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FEATURES 5 V 3-Channel Audio DAC System Accepts Sample Rates kHz 7 Biquad Filter Sections per Channel Dual Dynamic Processor with Arbitrary Input/Output Curve and Adjustable Time Constants Variable Delay/Channel for Speaker ...
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AD1954 TABLE OF CONTENTS FEATURES/APPLICATIONS . . . . . . . . . . . . . . . . . . . . . . . .1 GENERAL DESCRIPTION . . . . . . . . . ...
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AD1954–SPECIFICATIONS Test conditions, unless otherwise noted. Supply Voltages ( 5 Ambient Temperature 25°C Input Clock 12.288 MHz Input Signal 1.000 kHz 0 dB Full Scale Input Sample Rate 48 kHz Measurement Bandwidth 20 Hz ...
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AD1954 SPECIFICATIONS (continued) DIGITAL I/O Parameter Input Voltage High ( Input Voltage High (V ) – RESETB IH Input Voltage Low ( Input Leakage ( 2 Input Leakage (I @ ...
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DIGITAL TIMING Parameter t MCLK Recommended Duty Cycle @ 12.288 MHz (256 f Mode) MCLK Recommended Duty Cycle @ 12.288 MHz (256 f MCLK Recommended Duty Cycle @ 12.288 MHz (256 f DMDC t MCLK Recommended Duty Cycle @ 24.576 ...
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... AD1954YSRL AD1954YST AD1954YSTRL AD1954YSTRL7 EVAL-AD1954EB CAUTION ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the AD1954 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges ...
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Pin No. Pin No. (44-MQFP) (48-LQFP) Mnemonic MCLK2 2 3 MCLK1 3 4 MCLK0 4 5 DEEMP/ SDATA_AUX 5 6 MUTE 6 7 DVDD 7 8 SDATA2 8 9 BCLK2 9 10 LRCLK2 10 11 SDATA1 ...
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AD1954–Typical Performance Characteristics PERFORMANCE PLOTS The following plots demonstrate the performance achieved on the actual silicon.TPC 1 shows an FFT of a full-scale 1 kHz signal, with a THD+N of –100 dB, which is dominated by a second harmonic.TPC 2 ...
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GENERAL DESCRIPTION (continued from page 1) An extensive SPI port allows click-free parameter updates, along with read-back capability from any point in the algorithm flow. The AD1954 includes ADI’s patented multibit - DAC architec- ture.This architecture provides 112 dB SNR ...
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AD1954 The AD1954 has a very flexible serial data input port, which allows for glueless interconnection to a variety of ADCs, DSP chips, AES/EBU receivers, and sample rate converters. The AD1954 can be configured in left-justified, I DSP serial port ...
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DCSOUT—Data Capture Serial Out This pin will output the DSP’s internal signals, which can be used by external DACs or other signal processing devices. The signals that are captured and output on the DCSOUT pin are controlled by writing program ...
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... A graphical user interface (GUI) is available for evaluation of the AD1954 (Figure 3). This GUI controls all of the functions of the chip in a very straightforward and user friendly interface. No code needs to be written to use the GUI to control the chip ...
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SIGN EXTENTION DATA IN SERIAL PORT 1. and 1/0.75 (approximately 3 dB) will produce larger analog outputs and result in slightly degraded analog performance. This extra analog range is necessary in order to pass 0 dBFS square ...
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AD1954 – –1 Z Figure 5. Biquad Filter This section implements the transfer function × – − × – ...
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Alpha_Spread 1.0 – EXP where EXP is the exponential operator, EXP is the exponential operator, EXP Spread_Freq is the low-pass ...
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AD1954 INPUT WAVEFORM HOLD TIME, SPI- PROGRAMMABLE Figure 9. Using the Hold and ReleaseTime Feature Using this idea of a modified rms algorithm, the true rms value is still obtained for all but the lowest frequency signals, while the distortion ...
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In the look-ahead compressor, the gain has already been reduced by the time that the tone-burst signal arrives at the multiplier input. Note that when using a look-ahead compressor important to set the detector hold time to a ...
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AD1954 The biquad filter before the detector can be used to implement a frequency-dependent compression threshold. For example, assume that the overload point of the woofer is very frequency depen- dent. In this case, one would have to set the ...
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SPI PORT Overview The AD1954 has many different control options. Most signal processing parameters are controlled by writing new values to the parameter RAM using the SPI port. Other functions, such as volume and de-emphasis filtering, are programmed by writing ...
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AD1954 SPI Address Register Name 0–255 Parameter RAM 256 SPI Control Register 1 257 SPI Control Register 2 258 Volume Left 259 Volume Right 260 Volume Sub 261 Data Capture (SPI Out) #1 262 Data Capture (SPI Out) #2 263 ...
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The initiate-safe-transfer Bit 9 will request a data transfer from the SPI safeload registers to the parameter RAM. The safeload registers contain address-data pairs, and only those registers that have been written to since the last transfer operation will be ...
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AD1954 Bit 8 is used to enable the three serial output pins. These pins are connected to the output of the serial input mux, which is set by Bits 7 and 6. The default is 0 (disabled). Bit 9 changes ...
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Table VI. Parameter RAM Contents—Default Program Default Value in Fractional Addr Function 2.20 Format 0 IIR0 Left b0 1.0 1 IIR0 Left IIR0 Left IIR0 Left IIR0 Left ...
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AD1954 that lasts for ms. Again, this reduces the chance of any pop or click noise from occurring. Note that this shutdown sequence assumes that the part is set to the fast volume ramp speed (Control ...
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Table XI. Program RAM Read/Write Format (Burst Address) Byte 0 Byte 1 Byte 2 00000, R/W 00000, R/W 00000 Addr[9:8] Addr[7:0] 00000, Prog[34:32] Prog[31:24] Prog[23:16] Byte 0 00000 Addr[9:8] 00000, R/W 00000, R/W Byte 0 00000, ...
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AD1954 INITIALIZATION Power-Up Sequence The AD1954 has a built-in power-up sequence that initializes the contents of the internal RAMs. During this time, the contents of the internal program boot ROM are copied to the internal program RAM memory, and likewise, ...
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The format of the captured data varies according to the register select fields. Data captured from the mult_out setting is in 1.23 twos complement format so that a full-scale input signal will produce a full-scale digital output (assuming no processing). ...
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AD1954 Table XX. Data Capture Trap Indexes and Register Select—Default Program Signal Description HPF Out Left HPF Out Right De-emphasis Out Left De-emphasis Out Right Left Biquad 0 Output Left Biquad 1 Output Left Biquad 2 Output Left Biquad 3 ...
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LRCLK LEFT CHANNEL BCLK SDATA MSB LRCLK BCLK SDATA MSB LRCLK LEFT CHANNEL BCLK SDATA MSB LRCLK BCLK SDATA MSB NOTES 1. DSP MODE DOESN’T IDENTIFY CHANNEL. 2. LRCLK NORMALLY OPERATES AT 3. BCLK FREQUENCY IS NORMALLY 64 LRCLK ...
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AD1954 ANALOG OUTPUTSECTION Figure 21 shows the block diagram of the analog output section. A series of current sources are controlled by a digital - modu- lator. Depending on the digital code from the modulator, each current source is connected ...
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GRAPHICAL CUSTOM PROGRAMMING TOOLS Custom programming tools are available for the AD1954 from ADI. These graphical tools allow the user to modify the default signal processing flow by individually placing each block (e.g., biquad filter, Phat Stereo, dynamics processor) and ...
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AD1954 APPENDIX Cookbook Formulae for Audio EQ Biquad Coefficients (Adapted from Robert Bristow-Johnson’s Internet Posting) For designing a parametric EQ, follow the steps below. 1. Given: Frequency Q dB_Gain Sample_Rate 2. Compute intermediate variables: (dB_Gain/40 = ...
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MAX 1.80 0.10 MIN VIEW A ROTATED 90 CCW 1.45 1.40 1.35 0.15 SEATING 0.05 PLANE ROTATED 90 CCW REV. A OUTLINE DIMENSIONS 44-Lead Metric Quad Flat Package [MQFP] (S-44) Dimensions shown in millimeters 1.03 0.88 2.45 ...
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AD1954 Revision History Location 8/03—Data Sheet changed from REV REV. A. Changes to SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . ...
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