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AD9834 DDS circuit project

Using the AD9834 75 MHz low power DDS device capable of producing high performance sine and triangular outputs.
AD9834 has an on-board comparator that allows a square wave to be produced for clock generation. Consuming only 20 mW of power at 3 V makes the AD9834 an ideal candidate for power-sensitive applications.
Capability for phase modulation and frequency modulation is provided. The frequency registers are 28 bits; with a 75 MHz clock rate, resolution of 0.28 Hz can be achieved. Similarly, with a 1 MHz clock rate, the AD9834 can be tuned to 0.004 Hz resolution. Frequency and phase modulation are affected by loading registers through the serial interface and toggling the registers using software or the FSELECT pin and PSELECT pin, respectively.
The AD9834 is written to using a 3-wire serial interface. This serial interface operates at clock rates up to 40 MHz and is compatible with DSP and microcontroller standards.
The DDS electronic project operates with a power supply from 2.3 V to 5.5 V DC. The analog and digital sections are independent and can be run from different power supplies, for example, AVDD can equal 5 V with DVDD equal to 3 V.

A low-pass filter is generally placed between the output of the DAC and the input of the comparator to further suppress the effects of aliased images.
One of the areas where the AD9834 is suitable is in modulation applications. The part can be used to perform simple modulation such as FSK. More complex modulation schemes such as GMSK and QPSK can also be implemented using the AD9834.

In an FSK application, the two frequency registers of the AD9834 are loaded with different values. One frequency represents the space frequency, and the other represents the mark frequency. The digital data stream is fed to the FSELECT pin, causing the AD9834 to modulate the carrier frequency between the two values.

The AD9834 has two phase registers, enabling the part to perform PSK. With phase shift keying, the carrier frequency is phase shifted, the phase being altered by an amount that is related to the bit stream that is input to the modulator.
The AD9834 is also suitable for signal generator applications. With the on-board comparator, the device can be used to generate a square wave.

Using this evaluation board of the AD9834 DDS IC you can easy program this chip for the application you need , using software from analog website .
AD9834 simple DDS electronic circuit project

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