module V_amp(in,out);
 input in;
 output out;
 voltage in,out;

 parameter real vin_offset = 0,         // input dc offset
                vout_offset= 0,         // output dc offset
                gain       = 1;         // amplifier gain

 analog
   V(out) <+ gain * (V(in)-vin_offset) + vout_offset;

endmodule