Voltage of power aupply decreases suddenly

[rizwanspirit]

Hi,
I am getting a problem with my circuit , consisting of a dsp kit and an AVR controller circuit. Whenever i connect my power supply to the circuit voltage gets decreased suddenly from 7v to 3.3v ,
I am hasitating to work on this circuit as i dont know it is some sort of short circuit or any other issue. Kindly guide me on this situation as soon as possible.

Thanks

 

[nandhu015]

Details provided is not sufficient to answer your question.

Post your circuit diagram mentioning power source used for this circuit