Analog Devices AD7091R User Manual Download

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AD7091R User Guide

Rev. 0 | Page 4 of 20

EVALUATION BOARD HARDWARE

DEVICE DESCRIPTION

This user guide describes the evaluation board for the

AD7091R

analog-to-digital converter.

The

AD7091R

is a 12-bit, ultralow power, successive approxima-

tion ADC. The

AD7091R

operates from a single 2.7 V to 5.25 V

power supply and is capable of achieving a throughput rate of
1 MSPS. The

AD7091R

also features an on-chip conversion

clock, an accurate reference, and a high speed serial interface.
The conversion process and data acquisition are controlled

using a CONVST signal and an internal oscillator. The

AD7091R

has a serial interface allowing data to be read after the conver-
sion, while achieving 1 MSPS throughput rate. The AD7091R
uses advanced design and process techniques to achieve
ultralow power dissipation at high throughput rates. An on-
chip, accurate 2.5 V reference is available.
Complete specifications for the

AD7091R

are provided in the

AD7091R

data sheet, available from Analog Devices, which

should be consulted in conjunction with this user guide when
using the evaluation board.
Full details on the

EVAL-SDP-CB1Z

are available at

http://www.analog.com/EVAL-SDP-CB1Z

HARDWARE LINK OPTIONS

The functions of the link options are described in Table 2.
The default setup is configured to operate the board with
the mains power supply adapter and to interface to the

EVAL-SDP-CB1Z

board.

POWER SUPPLIES

Care should be taken before applying power and signals to
the evaluation board to ensure that all link positions are set
according to the required operating mode. See Table 2 for the
complete list of link options.
This evaluation board is supplied with a wall-mountable
switching power supply that provides a 9 V dc output. Connect
the supply to a 100 V to 240 V ac wall outlet at 50 Hz to 60 Hz.

The output from the supply is provided through a 2.0 mm inner
diameter jack that connects to the evaluation board at J1. The 9
V supply is connected to the on-board 5 V linear regulator that
supplies the correct bias to each of the various sections on the
board and the

EVAL-SDP-CB1Z

board.

When using this evaluation board with the

EVAL-SDP-CB1Z

board, it is necessary to power the board through the J1
connector.
If the evaluation board is used without the 9 V adapter, an
external power supply in the range of 2.7 V to 5.25 V must be
connected to the VDD input to supply the

AD7091R

pin. In

addition, an external supply in the range of 1.65 V to 5.25 V
must be connected to the VDRIVE input to supply the

AD7091R

DRIVE

pin.

Each supply is decoupled on this board using 10 µF tantalum
and 100 nF multilayer ceramic capacitors.
There are two main ground planes, AGND and DGND. These
are connected at one location close to the

AD7091R

Caution

When the

EVAL-AD7091RSDZ

evaluation board is connected to

the

EVAL-SDP-CB1Z

, care must be taken to ensure that, if an

external voltage is supplied to the VDRIVE input connector, J3,
the voltage does not exceed 3.3 V. Otherwise, permanent
damage may occur to the

EVAL-SDP-CB1Z

board.

Table 1. External Power Supplies Required