### Q

What is the precison can I except on temperature range: the output is 0.65V max+/- ???

Do you confirm that the rejection of 2nd harmonic is 65 dB.

### A

The frequency precision of any DDS system is as goodas its reference frequency. The AD9833 & AD9834 use

external reference source, so that reference must have

the frequency stability that you need in your system.

The output of the DAC is a current into a 200 Ohm load.

The scale factor is defined by the reference. The AD9833

has a TC of 200 ppm/°C (Max) and the AD9834 has a TC of

100 ppm/°C (Max) so the worst case amplitude stability

will be 200 or 200 ppm/°C depending on which device you

choose.

The THD of these devices (sine wave output) is typically

-66 dB, but can be as bad, at some frequency codes, as

-56 dB. You should be able to build a generator with

-65 dB 2nd harmonic without much trouble if you can choose

your reference frequency/division ration or use quite a

simple filter at the output (or, of course, both).

To raise the current output of the device to a 10V p-p

signal you should use an op-amp in I-V mode.