AD7870SQ Analog Devices Inc, AD7870SQ Datasheet
AD7870SQ
Specifications of AD7870SQ
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AD7870SQ Summary of contents
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FEATURES Complete monolithic 12-bit ADCs with 2 μs track-and-hold amplifier 8 μs ADC On-chip reference Laser-trimmed clock Parallel, byte, and serial digital interface 72 dB SNR at 10 kHz input frequency (AD7870, AD7875 data access time Low power: ...
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AD7870/AD7875/AD7876 TABLE OF CONTENTS Features .............................................................................................. 1 Functional Block Diagram .............................................................. 1 General Description ......................................................................... 1 Product Highlights ........................................................................... 1 Revision History ............................................................................... 2 Specifications ..................................................................................... 3 AD7870 Specifications ................................................................. 3 AD7875/AD7876 Specifications ................................................. 4 Timing Characteristics ................................................................ 6 Absolute ...
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SPECIFICATIONS ± 5 −5 V ± 5%, AGND = DGND = unless otherwise noted. max AD7870 SPECIFICATIONS Table 1. Parameter 2 DYNAMIC PERFORMANCE 3 Signal-to-Noise Ratio (SNR) ...
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AD7870/AD7875/AD7876 Parameter CONVERSION TIME External Clock (f = 2.5 MHz) CLK 6 Internal Clock POWER REQUIREMENTS Power Dissipation 1 The temperature range for the J, K, and L versions is from 0°C ...
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Parameter ANALOG INPUT AD7875 Input Voltage Range AD7875 Input Current AD7876 Input Voltage Range AD7876 Input Current REFERENCE OUTPUT REF OUT @ +25°C REF OUT Tempco Reference Load Sensitivity (ΔREF OUT/ΔI) LOGIC INPUTS Input High Voltage, V INH Input Low ...
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AD7870/AD7875/AD7876 TIMING CHARACTERISTICS ± 5 −5 V ± 5%, AGND = DGND = 0 V. See Figure 14, Figure 15, Figure 16, and Figure 17. Timing specifications are DD SS sample tested at 25°C ...
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ABSOLUTE MAXIMUM RATINGS Table 4. Parameter V to AGND AGND SS AGND to DGND V to AGND IN REF OUT to AGND Digital Inputs to DGND Digital Outputs to DGND Operating Temperature Range Commercial ( ...
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AD7870/AD7875/AD7876 PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS BUSY/INT 2 23 AD7870/ CLK 3 22 AD7875/ DB11/HBEN 4 21 AD7876 DB10/SSTRB 5 20 DB9/SCLK 6 19 TOP VIEW DB8/SDATA 7 18 (Not to Scale) DB7/LOW 8 17 DB6/LOW 9 ...
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DIP and SOIC PLCC Pin No. Pin No. Mnemonic 18 21 AGND 19 23 REF OUT 12/8/CLK 23 27 CONVST Table 6. Output Data for Byte Interfacing ...
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AD7870/AD7875/AD7876 LOAD CIRCUITS DBN DBN 56kΩ 50pF DGND HIGH Figure 4. Load Circuits for Access Time 5V 56kΩ 50pF DGND HIGH Rev Page 3kΩ DBN DBN 3kΩ 10pF ...
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CONVERTER DETAILS The AD7870/AD7875/AD7876 is a complete 12-bit ADC, requiring no external components apart from power supply decoupling capacitors comprised of a 12-bit successive approximation ADC based on a fast settling voltage output DAC, a high speed comparator ...
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AD7870/AD7875/AD7876 AD7876 TRACK-AND-HOLD AMPLIFIER 2. INTERNAL REF OUT REFERENCE TO INTERNAL AGND AGND Figure 9. AD7876 Analog Input Figure 10 shows the analog input for the AD7875. The input range ...
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R1 10kΩ 500Ω R4 10kΩ 10kΩ 10kΩ 1 ADDITIONAL PINS OMITTED FOR CLARITY. Figure 13. Offset and Full-Scale Adjust Circuit Positive Full-Scale Adjust Apply a voltage of 2.9978 V (FS/2 − 3/2 LSBs ...
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AD7870/AD7875/AD7876 TIMING AND CONTROL The AD7870/AD7875/AD7876 is capable of two basic operat- ing modes. In the first mode (Mode 1), the CONVST line is used to start conversion and drive the track-and-hold into its hold mode. At the end of ...
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CONVST CS RD INT DATA t 1 CONVST TRACK-AND-HOLD GOES INTO HOLD 1 HBEN CS RD TRACK-AND-HOLD RETURNS TO TRACK INT THREE-STATE DATA 2 SSTRB SCLK LEADING 2 SDATA ZEROS TIMES ...
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AD7870/AD7875/AD7876 BUSY DATA 1 HBEN t 19 TRACK-AND-HOLD CS GOES INTO HOLD BUSY THREE-STATE DATA 2 SSTRB SCLK 2 SDATA TIMES , , AND ...
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Fourier transform (FFT) plot is generated from which the SNR data can be obtained. Figure 18 shows a typical 2048 point FFT plot of the AD7870KN/AD7875KN with an input signal of 25 kHz and a sampling frequency of 100 kHz. ...
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AD7870/AD7875/AD7876 0 INPUT FREQUENCIES F1 = 9.05kHz F2 = 9.55kHz SAMPLING FREQUENCY = 100kHz T = 25°C –30 A IMD ALL TERMS = 90.06dB SECOND ORDER TERMS = 92.73dB THIRD ORDER TERSM = 93.45dB –60 –90 –120 0 FREQUENCY (kHz) ...
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MICROPROCESSOR INTERFACE The AD7870/AD7875/AD7876 have a wide variety of interfacing options. They offer two operating modes and three data-output formats. Fast data access times allow direct interfacing to most microprocessors including the DSP processors. PARALLEL READ INTERFACING Figure 22, Figure ...
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AD7870/AD7875/AD7876 This is a two-byte read instruction. During the first read operation BUSY , in conjunction with CS , forces the micro- processor to WAIT for the ADC conversion. At the end of conversion the ADC low byte (DB7 – ...
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TMS32020 Serial Interface Figure 28 shows a serial interface between the AD7870/ AD7875/AD7876 and the TMS32020. The AD7870/AD7875/ AD7876 is configured for continuous clock operation. Note that the ADC will not interface correctly to the TMS32020 if the ADC is ...
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AD7870/AD7875/AD7876 APPLICATIONS INFORMATION Good printed circuit board (PCB) layout is as important as the overall circuit design itself in achieving high speed analog- to-digital performance. The designer has to be conscious of noise both in the ADC itself and in ...
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OUTLINE DIMENSIONS 24 1 0.210 (5.33) MAX 0.150 (3.81) 0.130 (3.30) 0.115 (2.92) 0.022 (0.56) 0.018 (0.46) 0.014 (0.36) CONTROLLING DIMENSIONS ARE IN INCHES; MILLIMETER DIMENSIONS (IN PARENTHESES) ARE ROUNDED-OFF INCH EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR ...
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AD7870/AD7875/AD7876 0.048 (1.22) 0.042 (1.07) 4 0.048 (1.22) 5 0.042 (1.07) IDENTIFIER TOP VIEW (PINS DOWN 0.456 (11.582) 0.450 (11.430) 0.495 (12.57) 0.485 (12.32) 0.30 (0.0118) 0.10 (0.0039) COPLANARITY 0.10 0.180 (4.57) 0.165 (4.19) 0.056 (1.42) 0.020 (0.51) ...
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ORDERING GUIDE Table 7. Model Temperature Range AD7870JN 0°C to +70°C 1 AD7870JNZ 0°C to +70°C AD7870KN 0°C to +70°C 1 AD7870KNZ 0°C to +70°C AD7870LN 0°C to +70°C AD7870LNZ 1 0°C to +70°C AD7870JP 0°C to +70°C AD7870JP-REEL 0°C ...
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AD7870/AD7875/AD7876 NOTES Rev Page ...
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NOTES AD7870/AD7875/AD7876 Rev Page ...
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AD7870/AD7875/AD7876 NOTES ©1997–2009 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D07730-0-2/09(C) Rev Page ...