How can I drive a 5volt peak to peak sinusoid to analog input pin

Facing a big problem when the sine wave generated by a signal conditioner is given to A0 in of arduino I have a dac which converts pwm back to analog but at the output I get only a half wave rectified signal since the arduino uno doesn’t have a bidirectional ADC…
I tried to use a clamper with a diode IN4007 and capacitor 10 micro farad to clamp the signal up by 2.5 volts and then apply it to the input of arduino but it doesn’t seem to be working…(Positive clamper)
Im not sure if the clamping circuit is working or I should try to use another circuit for generation of an offset…
How should I proceed with this hurdle… ?

There is a bias circuit on [u]this page[/u]. Two equal-value resistors create a voltage divider. The 10uF capacitor isolates the bias from the AC signal/circuit. (You can leave-out the 47nF cap.)

You can subtract-out the bias/offset in software necessary for your application.

Is the signal from -2.5V to +2.5V ? You can use the three resistor voltage divider for that.