AD7914 Analog Devices, AD7914 Datasheet
AD7914
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AD7914 Summary of contents
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... Four Single-Ended Inputs with Channel Sequencer. A consecutive sequence of channels can be selected, through which the ADC will cycle and convert on. 3. Single-Supply Operation with V The AD7904/AD7914/AD7924 operate from a single 2 5.25 V supply. The V face to connect directly processor systems, independent ...
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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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... AD7914 SPECIFICATIONS 2 5.25 V, REF = 2 DRIVE IN Table 2. 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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... 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 @ models @ models @ 3 V, typically 69 models W models @ 5 V, typically − ...
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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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... AD7904/AD7914/AD7924 TYPICAL PERFORMANCE CHARACTERISTICS –10 –30 –50 –70 –90 –110 0 50 100 150 200 250 300 FREQUENCY (kHz) Figure 4. AD7924 Dynamic Performance at 1 MSPS 1MSPS SAMPLE 25°C A RANGE = 0V TO REF 100 INPUT FREQUENCY (kHz) Figure 5. AD7924 SINAD vs. Analog Input Frequency for Various Supply ...
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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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... ADD1 and ADD0, in each previous write operation. 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). ...
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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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... ADC TRANSFER FUNCTION The output coding of the AD7904/AD7914/AD7924 is either straight binary or twos complement, depending on the status of the LSB in the control register. The designed code transitions occur at successive LSB values (that is, 1 LSB, 2 LSBs, and so on). For the REF input range, the LSB size is REF ...
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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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... An external reference source should be used to supply the 2 there is no risk of 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 ...
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... FULL SHUTDOWN MODE (PM1 = 1, PM0 = 0) In full shutdown mode, all internal circuitry on the AD7904/ 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. ...
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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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... MSB (the WRITE bit) has been set to 1. The AD7904 outputs two leading zeros, two channel address bits that the conversion result corresponds to, followed by the 8-bit conversion result and four trailing zeros. The AD7914 outputs two leading zeros, two channel address bits that the 250 ...
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... Figure 27. AD7904 Serial Interface Timing Diagram t CONVERT ADD0 DB9 DB8 DB2 t 10 DONTC ADD1 ADD0 CODING Figure 28. AD7914 Serial Interface Timing Diagram t CONVERT ADD0 DB11 DB10 DB4 t 10 DONTC ADD1 ADD0 CODING Figure 29 ...
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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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... All four AGND pins of the AD7904/ AD7914/AD7924 should be sunk in the AGND plane. Digital and analog ground planes should be joined at only one place. If the AD7904/AD7914/AD7924 are in a system where multiple ...
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... EVALUATING AD7904/AD7914/AD7924 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) ...
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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 ...