I am looking for Amplitude Control of Sine wave from( 0.5VAC to 5.5VAC) with Frequency of 400Hz,
Amplitude Control thought microcontroller or thought SPI interface,
The about link is Somewhat okay but, It Can give Sine wave from ( 0.1VAC to 0.6VAC) only..
Plz Help me how to Achieve Sine wave from( 0.5VAC to 5.5VAC) which can be Amplitude Control thought microcontroller
The datasheet for the AD9834 is indeed a bit light on signal conditioning for the output signal, but fundamentally, the outputs are two complementary current sources, with a compliance voltage of +0.6V. That is, if the output load resistance is too high such that the output voltage exceeds 0.6V, performance may be degraded.
In order to achieve a 5.5V output, you will need a gain stage. A useful reference would be the LTC1668 datasheet - while the LTC1668 outputs sink current (vs the AD9834, which sources), the idea is the same. The LTC1668 eval board has three different output circuits that you could refer to: