voltage level shifting

Thread Starter


Joined Feb 12, 2009
Iam new to the world of analog electronics,
Brifly, my problem is as following:
i want to capture a speech signal using electret microphone
iam restricted with a circuit that consists a preamplifier and ADC
the following is there data sheet:-
LTC6912 Dual Programmable Gain Amplifiers with Serial Digital Interface
LTC1407A-1 Serial 14-bit Simultaneous Sampling ADCs with Shutdown

this circuits accepts volatge inpute range between (0.4v to 2.9v), but the output of my electret mic is approximatily between (-1v to +1v)
also, iam restricted with a 3.3v VCC.
so, how can i make this circuit accept the speech signal(1v p-p).
Can any one give me a circuit with the powering cct of mic that do this task .
please i need your help...