AD7400 Analog Devices, AD7400 Datasheet
AD7400
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AD7400 Summary of contents
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... Analog Devices, Inc. iCoupler® technology. The AD7400 operates from power supply and accepts a differential input signal of ±200 mV (±320 mV full scale). The analog input is continuously sampled by the analog modulator, eliminating the need for external sample-and-hold circuitry ...
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... Circuit Information.................................................................... 13 Analog Input ............................................................................... 13 Differential Inputs ...................................................................... 14 Digital Filter ................................................................................ 15 Applications Information .............................................................. 17 Grounding and Layout .............................................................. 17 Evaluating the AD7400 Performance ...................................... 17 Insulation Lifetime ..................................................................... 17 Outline Dimensions ....................................................................... 18 Ordering Guide .......................................................................... 18 9/07—Rev Rev. B Updated VDE Certification Throughout ......................................1 Changes to Table 6.............................................................................7 12/06— ...
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... V max 4.5/5.25 V min/V max 3/5.5 V min/V max 12 mA max 6 mA max 4 mA max Rev Page AD7400 = MIN MAX 1 Test Conditions/Comments Filter output truncated to 16 bits −40°C to +85°C; ±2 LSB typical >85°C to 105°C Guaranteed no missing codes to 16 bits T = 25° ...
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... AD7400 TIMING SPECIFICATIONS DD1 DD2 Table 2. Parameter Limit MIN MAX MCLKOUT 9/ 0.4 × MCLKOUT t 0.4 × MCLKOUT 1 Sample tested during initial release to ensure compliance. 2 Mark space ratio for clock output is 40/60 to 60/40. ...
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... File 205078 1 In accordance with UL 1577, each AD7400 is proof tested by applying an insulation test voltage ≥ 6000 V rms for 1 second (current leakage detection limit = 15 μA accordance with DIN V VDE V 0884-10, each AD7400 is proof tested by applying an insulation test voltage ≥ 1671 V peak for 1 second (partial discharge detection limit = 5 pC) ...
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... AD7400 DIN V VDE V 0884-10 (VDE V 0884-10) INSULATION CHARACTERISTICS This isolator is suitable for reinforced electrical isolation only within the safety limit data. Maintenance of the safety data is ensured by means of protective circuits. Table 5. Description INSTALLATION CLASSIFICATION PER DIN VDE 0110 For Rated Mains Voltage ≤ 300 V rms For Rated Mains Voltage ≤ ...
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... Refers to continuous voltage magnitude imposed across the isolation barrier. See the Insulation Lifetime section for more details. 1.7 pF typ 260 (+0)°C ESD CAUTION 1.5 kV Rev Page AD7400 1 Max Unit Constraint 565 V 50-year minimum lifetime PK 891 V Maximum CSA/VDE PK approved working voltage ...
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... AD7400 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 8. Pin Function Descriptions Pin No. Mnemonic Description 1 V Supply Voltage. 4 5.25 V. This is the supply voltage for the isolated side of the AD7400 and is relative to DD1 GND . Positive Analog Input. Specified range of ±200 mV − ...
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... Figure 10. Typical DNL, ±200 mV Range 3 (Using Sinc Filter, 256 Decimation Rate) 0 –200mV TO +200mV IN V – 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 0 10000 20000 30000 40000 CODE Figure 11. Typical INL, ±200 mV Range 3 (Using Sinc Filter, 256 Decimation Rate) AD7400 = DD1 DD2 0.295 0.315 50000 60000 50000 60000 ...
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... AD7400 100 V DD1 DD1 DD2 –50 –100 5.25V DD1 DD2 –150 –200 –45 –35 –25 –15 – 105 TEMPERATURE (°C) Figure 12. Offset Drift vs. Temperature for Various Supply Voltages 0.20 0.15 0. 4.5V DD1 DD2 0. DD1 0 – ...
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... BANDWIDTH = 100kHz 0.8 0.6 0.4 0 INPUT (V) IN Figure 18. RMS Noise Voltage vs Input IN 11.0 10.8 10.6 10 DD1 10.2 10.0 9.8 9.6 9 DD1 DD2 9.2 9.0 Figure 19. MCLKOUT vs. Temperature for Various Supplies Rev Page AD7400 = 4.5V DD2 5.25V DD1 DD2 TEMPERATURE (°C) ...
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... Therefore, for a 12-bit converter, this is 74 dB. Effective Number of Bits (ENOB) The ENOB is defined by ENOB = (SINAD − 1.76)/6.02 Total Harmonic Distortion (THD) THD is the ratio of the rms sum of harmonics to the fundamental. For the AD7400 defined as THD where the rms amplitude of the fundamental. 1 ...
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... Negative Full Scale To reconstruct the original information, this output needs to be digitally filtered and decimated. A Sinc because this is one order higher than that of the AD7400 modulator 256 decimation rate is used, the resulting 16-bit word rate is 39 kHz, assuming a 10 MHz internal clock frequency ...
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... To remedy the situation, a low-pass RC filter can be connected between the amplifier and the input to the AD7400. The external capacitor at each input aids in supplying the current spikes created during the sampling process, and the resistor isolates the op amp from the transient nature of the load. ...
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... DIGITAL FILTER 3 A Sinc filter is recommended for use with the AD7400. This filter can be implemented on an FPGA or a DSP. The following Verilog code provides an example of a Sinc on a Xilinx® Spartan-II 2.5 V FPGA. This code can possibly be compiled for another FPGA, such as an Altera® device. Note that the data is read on the negative clock edge in this case, although it can be read on the positive edge if preferred ...
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... AD7400 always @ (posedge word_clk or posedge reset) if(reset) begin acc3_d2 <= 0; diff1_d <= 0; diff2_d <= 0; diff1 <= 0; diff2 <= 0; diff3 <= 0; end else begin diff1 <= acc3 - acc3_d2; diff2 <= diff1 - diff1_d; diff3 <= diff2 - diff2_d; acc3_d2 <= acc3; diff1_d <= diff1; diff2_d <= diff2; end /* Clock the Sinc output into an output ...
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... The value that ensures at least a 50-year lifetime of continuous use • The maximum CSA/VDE approved working voltage It should also be noted that the lifetime of the AD7400 varies according to the waveform type imposed across the isolation barrier. The iCoupler insulation structure is stressed differently depending on whether the waveform is bipolar ac, unipolar ac ...
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... REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN. ORDERING GUIDE 1 Model Temperature Range AD7400YRWZ −40°C to +105°C AD7400YRWZ-REEL −40°C to +105°C AD7400YRWZ-REEL7 −40°C to +105°C EVAL-AD7400EDZ EVAL-CED1Z RoHS Compliant Part. 10.50 (0.4134) 10.10 (0.3976 7.60 (0.2992) 7.40 (0.2913) 1 10.65 (0.4193 ...
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... NOTES Rev Page AD7400 ...
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... AD7400 NOTES ©2006–2011 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D04718-0-7/11(E) Rev Page ...