AD7912/AD7922 EVALUATION TOOLS

Introduction

The AD7912/AD7922 are 10 bit and 12 bit, high speed, low power, successive-approximation ADC's respectively. The parts operate from a single 2.35 V to 5.25 V power supply and feature throughput rates up to 1 MSPS.

The EVAL-AD7912CB and the EVAL-AD7922CB can be used to evaluate the AD7912 and the AD7922 respectively. Accompanying each evaluation kit is the AD7912/22CB evaluation board and a CD-ROM containing a Technical Note, the datasheet and a description for the Evaluation Board Controller. The Technical Note describes the evaluation board for the AD7912/AD7922. Full details on the AD7912/AD7922 are also available in the AD7912/AD7922 data sheet which is available from the AD7912 or AD7922 product pages. This should be consulted in conjunction with this Technical Note when using the Evaluation Board.

On-board components include an AD780, which is a pin programmable +2.5 V or +3 V ultra high precision bandgap reference, the ADR435 high precision, low noise voltage reference, providing a 5V reference voltage and the AD8022 dual op-amp used to buffer the analog inputs. There are various link options which are explained in detail on pages 2 and 3.

Interfacing to this board is through a 96-Way connector. This 96-Way connector is compatible with the Evaluation board controller (EVAL-CONTROL BRD2), which is also available from Analog Devices. External sockets are provided for SCLK, DIN, DOUT and CS signals, two biased-up circuits for bipolar input signals with sockets for the AIN and the VBIASED inputs, and two more sockets for the two analog input channels (VIN inputs).

Software

Included in the EVAL-AD7912CB and EVAL-AD7922CB evaluation board package is software for controlling and evaluating the performance of the AD7912 and AD7922 when it is operated with the EVALUATION BOARD CONTROLLER. The EVAL-AD7912/22CB Demonstration/Evaluation Software runs under Windows 95, 98, 2000 and NT. The user interface on the PC is via a dedicated program written especially for the EVAL-AD7912CB and EVAL-AD7922CB.