What is the switching frequency of DC/DC converters?

By analyzing the spectrum of the signal data from a XEM based data acquisition board, I noticed there is a noise peak at a frequency point of around 200kHz. I don’t know where the noise comes from, and am wondering if it is from the switching DC/DC converter on XEM3010. O-K, can you tell me what is the switching frequency of those on-board DC/DC converters ? Thanks.

Hengjie

The device is a Maxim MAX1831EEE+. Please see the datasheet for these converters to see that the switching frequency is a function of the load current.