EVAL-AD9835EB

a

FEATURES

Full-Featured Evaluation Board for the AD9835

Various Linking Options

PC Software for Control of AD9835

On-Board Patchwork Area

Information furnished by Analog Devices is believed to be accurate

and reliable. However, no responsibility is assumed by Analog Devices

for its use; nor for any infringements of patents or other rights of third

parties which may result from its use. No license is granted by implication

or otherwise under any patent or patent rights of Analog Devices.

OneTechnologyWay; P.O.BOX9106; Norwood, MA02062-9106 U.S.A.

Tel: 617/329-4700

Twx: 710/394-6577

Telex: 174059

Cables: ANALOG NORWOOD MASS

Rev. A

Components on the AD9835 Evaluation Board include a

50 MHz oscillator which provides the MCLK for the

AD9835.

The user can remove this oscillator, if required,

and drive the AD9835 with a different clock oscillator or

an external clock source via a BNC connector.

A digital

buffer is also on the board so that the signals from the

edge connector are buffered.

OPERATING THE AD9835 EVALUATION BOARD

Power Supplies

This evaluation board has two analog power supply inputs:

connections are also available.

are connected under the AD9835.

Therefore, it is

recommended not to connect AGND and DGND

elsewhere in the system.

All power supplies are decoupled to ground.

0.1µF ceramic capacitors at the input to the evaluation

board.

The power supplies are again decoupled using

0.1µF capacitors at the AD9835, the crystal and the logic.

Evaluation Board for the AD9835

Direct Digital Synthesizer

INTRODUCTION

This Application Note describes the evaluation board for

the AD9835 Direct Digital Synthesizer (DDS).

The

AD9835 is a numerically controlled oscillator employing

a phase accumulator, a sine look-up table and a 10-bit D/

A converter.

The part can be operated with clock

frequencies up to 50 MHz.

Both phase modulation and

frequency modulation can be performed with the AD9835.

Full data on the AD9835 is available in the AD9835

datasheet available from Analog Devices and should be

consulted in conjunction with this Application Note when

using the evaluation board.

The evaluation board interfaces to the parallel port of an

IBM compatible PC.

Software is available with the

evaluation board which allows the user to easily program

the AD9835.

Figure 1: Evaluation Board Setup

P a ra lle l P o rt C e n tro n ics

Prin te r C a b le

IB M C o m p a tib le P C

AD 98 35 .E XE

A D 98 35

E valuation B oard