AD7401 Analog Devices, AD7401 Datasheet
AD7401
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AD7401 Summary of contents
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... Analog Devices, Inc. iCoupler® technology. The AD7401 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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... Terminology .................................................................................... 12 Theory of Operation ...................................................................... 13 Circuit Information.................................................................... 13 Analog Input ............................................................................... 13 Differential Inputs ...................................................................... 14 Digital Filter ................................................................................ 15 Applications Information .............................................................. 17 Grounding and Layout .............................................................. 17 Evaluating the AD7401 Performance ...................................... 17 Insulation Lifetime ..................................................................... 17 Outline Dimensions ....................................................................... 18 Ordering Guide .......................................................................... 18 Changes to Table 2.............................................................................4 Changes to Table 6.............................................................................7 Changes to Table 8.............................................................................8 Changes to Circuit Information Section ..................................... 13 Changes to Figure 27...................................................................... 15 1/06— ...
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... MHz to <9 MHz MCLK >85°C to 105° MHz maximum ; −250 mV to +250 mV MCLK IN −40°C to +105° typ MHz maximum −250 mV to +250 mV MCLK MHz maximum ; −250 mV to +250 mV MCLK IN AD7401 , 4 4 ...
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... AD7401 Parameter LOGIC OUTPUTS Output High Voltage Output Low Voltage POWER REQUIREMENTS V DD1 V DD2 6 I DD1 7 I DD2 1 Temperature range is −40°C to +85°C. 2 All voltages are relative to their respective ground. 3 See the Terminology section. 4 For f > 16 MHz to 20 MHz, mark space ratio is 48/52 to 52/48, V ...
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... File 205078 1 In accordance with UL 1577, each AD7401 is proof tested by applying an insulation test voltage ≥ 4500 V rms for 1 second (current leakage detection limit = 7.5 μA accordance with DIN V VDE V 0884-10, each AD7401 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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... AD7401 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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... DC Voltage 89.2°C/W 1 Refers to continuous voltage magnitude imposed across the isolation 55.6°C/W barrier. See the 10 12 Ω ESD CAUTION 1.7 pF typ 260 (+0)°C 1.5 kV Rev Page AD7401 1 Max Unit Constraint 565 V 50-year minimum lifetime PK 891 V Maximum CSA/VDE PK approved working voltage 891 ...
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... AD7401 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 8. Pin Function Descriptions Pin No. Mnemonic Description Supply Voltage. 4 5.25 V. This is the supply voltage for the isolated side of the AD7401 and is relative to GND DD1 Positive Analog Input. Specified range of ±200 mV − ...
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... Figure 9. SINAD vs 0.4 0.3 0.2 0 –200mV TO +200mV IN V – 10k 20k 30k 40k CODE Figure 10. Typical DNL (±200 mV Range) 0 –200mV TO +200mV IN V – 0.6 0.4 0 10k 20k 30k 40k CODE Figure 11. Typical INL (±200 mV Range) AD7401 = DD2 0.33 50k 60k 50k 60k ...
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... AD7401 250 4. DD1 DD2 DD1 200 MCLKIN = 16MHz MCLKIN = 10MHz 4.5V V DD1 DD2 DD1 150 MCLKIN = 5MHz MCLKIN = 5MHz 100 DD1 DD2 MCLKIN = 16MHz 50 0 –50 –100 5.25V DD1 DD2 DD1 MCLKIN = 16MHz MCLKIN = 10MHz –150 ...
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... RIPPLE FREQUENCY (kHz) Figure 19. CMRR vs. Common-Mode Ripple Frequency 1.0 V DD1 50kHz BRICK WALL FILTER 0.8 0.6 0.4 MCLKIN = 5MHz 0.2 MCLKIN = 10MHz DD1 DD2 DD2 1000 Rev Page AD7401 = DD2 MCLKIN = 16MHz V DC INPUT (V) IN Figure 20. RMS Noise Voltage vs Input IN ...
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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 AD7401 defined as THD where the rms amplitude of the fundamental. 1 ...
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... 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 AD7401 modu- lator 256 decimation rate is used, the resulting 16-bit word rate is 62.5 kHz, assuming a 16 MHz external 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 AD7401. 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 AD7401. This filter can be implemented on an FPGA or possibly a DSP. The following Verilog code provides an example of a Sinc implementation on a Xylinx® Spartan-II 2.5 V FPGA. This code can possibly be compiled for another FPGA, such as an Altera® ...
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... AD7401 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 AD7401 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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... ORDERING GUIDE Model Temperature Range AD7401YRW −40°C to +105°C AD7401YRW-REEL −40°C to +105°C AD7401YRW-REEL7 −40°C to +105°C 1 AD7401YRWZ −40°C to +105°C 1 AD7401YRWZ-REEL −40°C to +105°C 1 AD7401YRWZ-REEL7 −40°C to +105°C 1 EVAL-AD7401EBZ RoHS Compliant Part. 10.50 (0.4134) 10.10 (0.3976 ...
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... NOTES Rev Page AD7401 ...
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... AD7401 NOTES ©2006–2007 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D05851-0-9/07(B) Rev Page ...