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.
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.

FEATURES
   Full-Featured Evaluation Board for the AD9835
   Various Linking Options
   PC Software for Control of AD9835
   On-Board Patchwork Area