small signal Transfer Function - pspice

.TF (Small Signal Transfer Function)

the small signal Transfer function capability of P Spice can be used to compute the small signal DC gain , the input resistance and the output resistance of a circuit.
If V(1) and V(4) are the input and output variables respectively, P Spice calculate the small signal dc gain between nodes 1 and 4,defibned by
AV = ∆ V out / ∆ V in = V(4) / V(1)
Pspice calculates the small signal dc transfer function by linearizing the circuit around the OP. The statement for transfer function has one of the following forms

.TF VOUT VIN
.TF IOUT IIN
The .TF command calculates the parameters of an equivalent circuit for the circuit file, it automatically prints the out put and does not require .PRINT, .PLOT, .PROBE statements

.DC (DC Sweep)
The dc sweep is also known as the dc transfer characteristic. The input variable is varied over a range of values. For each value of the input variable, the dc operating point and the small signal dc gain are computed.
The simple statement for dc sweep
.DC LIN SWNAME SSTART SEND SINC
.DC OCT SWNAME SSTART SEND NP
.DC DEC SWNAME SSTART SEND NP
.DC SWNAME LIST (Value)
SWNAME is the sweep variable (voltage or current).
SSTART → sweep start value
SEND → sweep end value
SINC → sweep incremental value (it must be positive, not –ve or zero)
NP→ number of steps
LIN→ linear sweep
OCT→ sweep by octave
DEC→ sweep by decade
LIST→ list of values