8 15-8 The transfer function(or network function) H(S) We define transfer function H(s)as a ratio of the Laplace transform of system output (or response) vo(s) to the Laplace transform of the input (or forcing function) vi(s)when all initial conditions are zero. then H(S) or Vo(s)=H(svi(s) (s) when Vi(s)=l Vo(s)=H(s) and V(s)=1 U()=(t) The inverse function corresponding to the transfer function H(s)is the unit-impulse response of the circuit. h(t)=L [H(s)=L o(s=0(§15-8 The transfer function(or network function) H(s) We define transfer function H(s) as a ratio of the Laplace transform of system output (or response) Vo (s) to the Laplace transform of the input (or forcing function) Vi (s) when all initial conditions are zero, then ( ) ( ) ( ) V s V s H s i O = or V (s) H(s)V (s) o = i when V (s) 1 V (s) H(s) i = o = and V (s) 1 (t) (t) i = i =  The inverse function corresponding to the transfer function H(s) is the unit-impulse response of the circuit. ( ) [ ( )] [ ( )] ( ) 1 1 h t L H s L V s t = = O =o − −