16-Bit Sigma Delta ADC with Current Sources, Switchable Reference Inputs and I/O Port
The AD7709 is a complete analog front-end for low frequency measurement applications. The AD7709 contains a 16-bit sigma delta ADC with PGA and can be configured as 2 fully-differential input channels or 4 pseudo-differential input channels. Inputs signal ranges from 20mV to 2.56V can be directly converted using the AD7709. These signals can be converted directly from a transducer without the need for signal conditioning. Other on-chip features include three software configurable current sources, switchable reference inputs, low side power switches and a 4-bit digital I/O port.
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation board for the AD7709, which is a Low Voltage, Low Power, 16-Bit, Sigma Delta ADC. The AD7709 is a complete analog front end for low frequency measurement applications. The device can accept low level input signals directly from a transducer and produce a serial digital output. It employs a sigma-delta conversion technique to realize up to 16 bits of no missing codes performance. The selected input signal is applied to a proprietary programmable gain front end based around an analog modulator. The modulator output is processed by an on-chip digital filter. The first notch of this digital filter can be programmed via an on-chip control register allowing adjustment of the filter cutoff and output update rate. The device also contains three switchable, ratioed current sources. Full data on the AD7709 is available in the AD7709 datasheet (available on the AD7709 Product Page) and should be consulted in conjunction with this Technical Note when using the evaluation board.
The analog DAC output, and ADC analog input can be accessed through SMA connectors or pin headers on the evaluation board. The jumper programmable interface configurations allow several different circuit options to suit different testing methods. An on-board digital loopback feature allows the ADC and DAC to be tested simultaneously with the use of a signal source and spectrum analyzer.
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The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.