Evaluation Board for 1 MSPS,

2-Channel, 12-/10-Bit ADCs

EVAL-AD7912/AD7922

Rev. 0

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FEATURES

Full-featured evaluation board for the AD7912/AD7922

EVAL-CONTROL-BRD2 compatible

Standalone capability

On-board analog buffering and reference

Various linking options

PC software for control and data analysis when used

with EVAL-CONTROL-BRD2

GENERAL DESCRIPTION

This data sheet describes the evaluation board for the AD7912/

AD7922. The AD7912/AD7922 are 12- and 10-bit, high speed,

low power successive-approximation ADCs, respectively. The

parts operate from a single 2.35 V to 5.25 V power supply and

feature throughput rates up to 1 MSPS. Full data on the AD7912/

AD7922 is available in the AD7912/AD7922 data sheet, which

is available from Analog Devices, Inc., and should be consulted in

conjunction with this data sheet when using the evaluation board.

On-board components include an AD780 (a pin-programmable,

2.5 V or 3 V, ultrahigh precision band gap reference), an ADR435

(a high precision, low noise voltage reference, providing a 5 V

reference voltage), and a AD8022 (a dual op amp used to buffer

the analog inputs). There are various link options, which are

explained in detail in Table 1.

Interfacing to this board is done through a 96-way connector.

This 96-way connector is compatible with EVAL-CONTROL-

BRD2, which is also available from Analog Devices. External

sockets are provided for the SCLK, DIN, DOUT, and CS signals;

the bipolar input signals at the AIN and the VBIASED inputs of

the two bias-up circuits; and the two analog input channels

(VIN inputs).

FUNCTIONAL BLOCK DIAGRAM

AD7912/AD7922

EVAL-AD7912/AD7922CB

EXTERNAL POWER

SUPPLY

BIAS-UP CIRCUIT

VBIASED

AIN

BIAS-UP CIRCUIT

VBIASED1

AIN1

VOLTAGE

REFERENCE

SCLK DOUT

DIN

CS

INPUT BUFFER

ANALOG

INPUTS

SCLK

DOUT

DIN

CS

POWER SUPPLY

CIRCUIT

Figure 1.