AD7924 Analog Devices, AD7924 Datasheet
AD7924
Specifications of AD7924
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AD7924 Summary of contents
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... The AD7904/AD7914/AD7924 use advanced design techniques to achieve very low power dissipation at maximum throughput rates. At maximum throughput rates, the AD7904/AD7914/ AD7924 consume 2 mA maximum with 3 V supplies; with 5 V supplies, the current consumption is 2.7 mA maximum. Through the configuration of the control register, the analog input range for the part can be selected REF 2 × ...
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... Modes of Operation ....................................................................... 22 Normal Mode (PM1 = PM0 = 1) ............................................. 22 Full Shutdown Mode (PM1 = 1, PM0 = 0) ............................. 22 Auto Shutdown Mode (PM1 = 0, PM0 = 1) ........................... 22 Powering Up the AD7904/AD7914/AD7924 ......................... 23 Power vs. Throughput Rate........................................................... 25 Serial Interface ............................................................................ 25 Applications Information .............................................................. 27 Microprocessor Interfacing....................................................... 27 ...
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... V V min DRIVE 0.3 × max DRIVE ±1 μA max 10 pF max Rev Page AD7904/AD7914/AD7924 , unless otherwise noted. Test Conditions/Comments kHz sine wave MHz IN SCLK B models W models B models W models fa = 40.1 kHz 41.5 kHz f = 400 kHz ...
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... AD7904/AD7914/AD7924 Parameter LOGIC OUTPUTS Output High Voltage Output Low Voltage Floating-State Leakage Current Floating-State Output Capacitance 3 Output Coding CONVERSION RATE Conversion Time 2 Track-and-Hold Acquisition Time Throughput Rate POWER REQUIREMENTS DRIVE Normal Mode (Static) Normal Mode (Operational) Auto Shutdown Mode ...
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... V V min DRIVE 0.3 × max DRIVE ±1 μA max 10 pF max Rev Page AD7904/AD7914/AD7924 , unless otherwise noted. Test Conditions/Comments kHz sine wave MHz IN SCLK B models W models B models W models fa = 40.1 kHz 41.5 kHz f = 400 kHz ...
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... AD7904/AD7914/AD7924 Parameter LOGIC OUTPUTS Output High Voltage Output Low Voltage Floating-State Leakage Current Floating-State Output Capacitance 3 Output Coding CONVERSION RATE Conversion Time 2 Track-and-Hold Acquisition Time Throughput Rate POWER REQUIREMENTS DRIVE Normal Mode (Static) Normal Mode (Operational) Auto Shutdown Mode ...
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... AD7924 SPECIFICATIONS 2 5.25 V, REF = 2 DRIVE IN Table 3. Parameter DYNAMIC PERFORMANCE Signal to (Noise + Distortion) (SINAD) Signal-to-Noise Ratio (SNR) 2 Total Harmonic Distortion (THD) Peak Harmonic or Spurious Noise (SFDR) Intermodulation Distortion (IMD) Second-Order Terms Third-Order Terms Aperture Delay Aperture Jitter 2 Channel-to-Channel Isolation ...
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... AD7904/AD7914/AD7924 Parameter LOGIC OUTPUTS Output High Voltage Output Low Voltage Floating-State Leakage Current Floating-State Output Capacitance 3 Output Coding CONVERSION RATE Conversion Time 2 Track-and-Hold Acquisition Time Throughput Rate POWER REQUIREMENTS DRIVE Normal Mode (Static) Normal Mode (Operational) Auto Shutdown Mode ...
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... F I 200µ OUTPUT PIN C L 50pF 200µ Figure 2. Load Circuit for Digital Output Timing Specifications Rev Page AD7904/AD7914/AD7924 ) and timed from a voltage level of 1.6 V (see Figure 2 DRIVE , quoted in the timing characteristics is the true bus relinquish 8 1.6V ...
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... AD7904/AD7914/AD7924 ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 5. Parameter AV to AGND AGND DRIVE Analog Input Voltage to AGND Digital Input Voltage to AGND Digital Output Voltage to AGND REF to AGND IN Input Current to Any Pin Except 1 Supplies Operating Temperature Range Commercial (B Version) ...
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... Serial Clock, Logic Input. SCLK provides the serial clock for accessing data from the part. This clock input is also used as the clock source for the AD7904/AD7914/AD7924 conversion process. 2 DIN Data In, Logic Input. Data to be written to the control register of the AD7904/AD7914/AD7924 is provided on this input and is clocked into the register on the falling edge of SCLK (see the Control Register section Chip Select ...
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... SAMPLE 25°C A RANGE = 0V TO REF 100 INPUT FREQUENCY (kHz) Figure 5. AD7924 SINAD vs. Analog Input Frequency for Various Supply Voltages at 1 MSPS, SCLK = 20 MHz 200mV p-p SINE WAVE ON AV –10 DD REF = 2.5V, 1µF CAPACITOR 25°C A –20 – ...
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... T = 25° DRIVE 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 –0.8 –1.0 0 512 1024 1536 2048 2560 3072 CODE Figure 10. AD7924 Typical DNL 3584 4 096 Rev Page AD7904/AD7914/AD7924 ...
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... Thus, for a 12-bit converter, SINAD is 74 dB, for a 10-bit IN converter dB, and for an 8-bit converter dB. Total Harmonic Distortion (THD) THD is the ratio of the rms sum of harmonics to the funda- mental. For the AD7904/AD7914/AD7924 defined LSB, THD IN where: IN point) ...
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... DONTC Don’t care bit. 1 RANGE This bit selects the analog input range to be used on the AD7904/AD7914/AD7924 set to 0, the analog input range will extend from × REF conversion). For the × REF 0 CODING This bit selects the type of output coding that the AD7904/AD7914/AD7924 will use for the conversion result. If this bit is set to 0, the output coding for the part will be twos complement ...
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... This mode of operation reflects the traditional operation of a multi- channel ADC, without using the sequencer function, where each write to the AD7904/AD7914/ AD7924 selects the next channel for conversion (see Figure 11). The sequencer function is not interrupted upon completion of the write operation. This config- uration allows other bits in the control register to be altered between conversions while in a sequence without terminating the cycle ...
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... ADD1, ADD0 IN THE CONTROL REGISTER CONTINUOUSLY CONVERTS ON THE SELECTED SEQUENCE OF CHANNELS BUT WILL ALLOW CS RANGE, CODING, AND SO FORTH, TO CHANGE IN THE CONTROL REGISTER WITHOUT INTERRUPTING THE SEQUENCE, PROVIDED SEQ1 = 1, SEQ0 = 0 Figure 12. SEQ1 Bit = 1, SEQ0 Bit = 1 Flowchart Rev Page AD7904/AD7914/AD7924 WRITE BIT = 0 WRITE BIT = 1, SEQ1 = 1, SEQ0 = 0 ...
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... The AD7904/AD7914/AD7924 are, respectively, 8-bit, 10-bit, and 12-bit, high speed, 4-channel, single-supply ADCs. The parts can be operated from a 2 5.25 V supply. When operated from either supply, the AD7904/AD7914/AD7924 are capable of throughput rates of 1 MSPS when provided with a 20 MHz clock. ...
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... For the REF input range, the LSB size is REF IN the AD7904, REF /1024 for the AD7914, and REF IN the AD7924. For the × REF input range, the LSB size × REF /256 for the AD7904, 2 × REF IN and 2 × ...
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... AD7924 (10 bits of data for the AD7914 and 8 bits of data for the AD7904, each followed by two and four trailing zeros, respectively). For applications where power ...
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... DD reference to the AD7904/AD7914/AD7924. Errors in the refer- ence source result in gain errors in the AD7904/AD7914 AD7924 transfer function and add to the specified full-scale errors of the part. A capacitor of at least 0.1 μF should be placed feature. on the REF DRIVE AD7914/AD7924 include the AD780, REF193, and AD1582. ...
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... AD7914/AD7924 is powered down. The part retains information in the control register during full shutdown. The AD7904/AD7914/ AD7924 remain in full shutdown until the power management bits in the control register, PM1 and PM0, are changed write to the control register occurs while the part is in full ...
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... CONTROL REGISTER IS LOADED ON THE FIRST 12 CLOCKS, PM1 = 0, PM0 = 1 POWERING UP THE AD7904/AD7914/AD7924 When supplies are first applied to the AD7904/AD7914/AD7924, the ADC may power up in any of the operating modes of the part. To ensure that the part is placed into the required operating mode, the user should perform a dummy cycle operation as shown in Figure 23, Figure 24, and Figure 25 ...
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... AFTER POWER- SCLK DOUT INVALID DATA DIN DIN LINE HIGH FOR FIRST DUMMY CONVERSION Figure 25. Placing the AD7904/AD7914/AD7924 into Auto Shutdown Mode After Supplies Are First Applied IF IN SHUTDOWN AT POWER-ON, PART BEGINS TO POWER UP ON ALLOW CS RISING EDGE AS PM1 = PM0 = ...
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... V). If the power-up time from auto shutdown DD is one dummy cycle, that is, 1 μs, and the remaining conversion time is another cycle, that is, 1 μs, then the AD7924 can be said to dissipate 13.5 mW for 2 μs during each conversion cycle. For the remainder of the conversion cycle, 8 μs, the part remains in shutdown. The AD7924 can be said to dissipate 2.5 μ ...
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... CONVERT ADD0 DB11 DB10 DB4 t 10 DONTC ADD1 ADD0 CODING Figure 29. AD7924 Serial Interface Timing Diagram Rev Page QUIET ZERO ZERO ZERO ZERO THREE- 4 TRAILING ZEROS STATE DONTC ...
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... The serial interface of the TMS320C541 uses a continuous serial clock and frame synchronization signals to synchronize the data transfer operations with peripheral devices such as the AD7904/ AD7914/AD7924. The CS input allows easy interfacing between the TMS320C541 and the AD7904/AD7914/AD7924 without any glue logic required. The serial port of the TMS320C541 is set up to operate in burst mode with internal CLKX0 (TX serial clock on Serial Port 0) and FSX0 (TX frame sync from Serial Port 0) ...
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... The analog ground plane should be allowed to run under the AD7904/AD7914/AD7924 to avoid noise coupling. The power supply lines to the AD7904/AD7914/ AD7924 should use as large a trace as possible to provide low impedance paths and reduce the effects of glitches on the power supply line. Fast switching signals such as clocks should be ...
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... PERFORMANCE The recommended layout for the AD7904/AD7914/AD7924 is outlined in the evaluation board for the AD7904/AD7914/ AD7924. The evaluation board package includes a fully assembled and tested evaluation board, documentation, and software for controlling the board from a PC via the evaluation board controller (EVAL-CONTROL-BRD2). The evaluation board controller ...
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... Evaluation Board Technical Note for more information. AUTOMOTIVE PRODUCTS The AD7904W/AD7914W/AD7924W models are available with controlled manufacturing to support the quality and reliability requirements of automotive applications. Note that these automotive models may have specifications that differ from the commercial models; therefore, designers should review the Specifications section of this data sheet carefully. Only the automotive grade products shown are available for use in automotive applications ...
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... NOTES AD7904/AD7914/AD7924 Rev Page ...
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... AD7904/AD7914/AD7924 NOTES ©2002–2011 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D03087-0-7/11(B) Rev Page ...