AD7829BRU-1 Analog Devices Inc, AD7829BRU-1 Datasheet
AD7829BRU-1
Specifications of AD7829BRU-1
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AD7829BRU-1 Summary of contents
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FEATURES 8-bit half-flash ADC with 420 ns conversion time Eight single-ended analog input channels Available with input offset adjust On-chip track-and-hold SNR performance given for input frequencies up to10 MHz On-chip reference (2.5 V) Automatic power-down at the end of ...
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AD7829-1 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 General Description ......................................................................... 1 Functional Block Diagram .............................................................. 1 Product Highlights ........................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Timing Characteristics ................................................................ 5 Timing Diagram ........................................................................... 5 Absolute Maximum Ratings............................................................ 6 ...
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SPECIFICATIONS ± 10 ± 10%, GND = Table 1. Parameter DYNAMIC PERFORMANCE 1 Signal to (Noise + Distortion) Ratio 1 Total Harmonic Distortion 1 Peak Harmonic or ...
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AD7829-1 Parameter LOGIC OUTPUTS Output High Voltage Output Low Voltage High Impedance Leakage Current High Impedance Capacitance CONVERSION RATE Track/Hold Acquisition Time Conversion Time POWER SUPPLY REJECTION V ± 10% DD POWER REQUIREMENTS ...
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TIMING CHARACTERISTICS V = 2.5 V. All specifications −40°C to +85°C, unless otherwise noted. REF IN/OUT Table Parameter 5 V ± 10 ± 10% t 420 420 ...
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AD7829-1 ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 3. Parameter V to AGND DGND DD Analog Input Voltage to AGND IN1 IN8 Reference Input Voltage to AGND V Input Voltage ...
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PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 4. Pin Function Descriptions Pin No. Mnemonic Description Analog Input Channels. The AD7829-1 has eight analog input channels. The inputs have an input span of 2.5 V IN8 ...
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AD7829-1 TERMINOLOGY Signal-to-(Noise + Distortion) Ratio The measured ratio of signal-to-(noise + distortion) at the output of the A/D converter. The signal is the rms amplitude of the fundamental. Noise is the rms sum of all nonfundamental signals up to ...
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Track/Hold Acquisition Time The time required for the output of the track/hold amplifier to reach its final value, within ±1/2 LSB, after the point at which the track/hold returns to track mode. This happens approxi- mately 120 ns after the ...
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AD7829-1 CIRCUIT INFORMATION CIRCUIT DESCRIPTION The AD7829-1 consists of a track-and-hold amplifier followed by a half-flash analog-to-digital converter. These devices use a half-flash conversion technique where one 4-bit flash ADC is used to achieve an 8-bit result. The 4-bit flash ...
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A suggestion is to tie CONVST DGND through a DD pull-up or pull-down resistor. A rising edge on the CONVST pin causes the AD7829-1 to fully power up. For applications where power consumption is of concern, the ...
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AD7829 2.5V MID N/C (1.25V) MID MID V = 1.5V MID V = N/C (1V) 1V MID Figure ...
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Capacitor C2 in Figure 13 is typically about 4 pF and can be primarily attributed to pin capacitance. The resistor, R1 lumped component made up of the on resistance of several components, including that of the multiplexer and ...
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AD7829 0 INPUT FREQUENCY (MHz) Figure 16. SNR vs. Input Frequency on the AD7829-1 POWER-UP TIMES The AD7829-1 has a 1 μs power-up time when using an external reference ...
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Figure 19 shows the power vs. throughput rate for automatic, full power-down. 100 100 150 200 250 300 THROUGHPUT (kSPS) Figure 19. AD7829-1 Power vs. Throughput 0 –10 –20 –30 –40 –50 –60 –70 ...
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AD7829-1 t POWER-UP CONVST EOC CS RD DB0 TO DB7 POWER DOWN HERE t 1 VALID DATA Figure 22. Mode 2 Operation Rev Page ...
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PARALLEL INTERFACE The parallel interface of the AD7829-1 is eight bits wide. Figure 23 shows a timing diagram illustrating the operational sequence of the AD7829-1 parallel interface. The multiplexer address is latched into the AD7829-1 on the falling edge of ...
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AD7829-1 MICROPROCESSOR INTERFACING The parallel port on the AD7829-1 allows the ADCs to be interfaced to a range of many different microcontrollers. This section explains how to interface the AD7829-1 with some of the more common microcontroller parallel interface protocols. ...
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AD7829 ADDRESS A15 DECODE RD DB7 TO DB0 Figure 27. AD7829-1 Simplified Microinterfacing Scheme MICROPROCESSOR READ CYCLE A15 DB0 TO DB7 MUX ADDRESS (CHANNEL SELECTION A0 ...
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... COPLANARITY 0.10 PIN 1 0.15 0.05 COPLANARITY ORDERING GUIDE Model Temperature Range AD7829BRU-1 −40°C to +85°C AD7829BRU-1REEL7 −40°C to +85°C 1 AD7829BRUZ-1 −40°C to +85°C 1 AD7829BRUZ-1REEL7 −40°C to +85°C AD7829BRW-1 −40°C to +85°C AD7829BRW-1RL7 −40°C to +85°C ...