Transfer function analysis calculates the small-signal DC
transfer function from a specified input source to a specified
output expression. Depending upon the input source and the
output expression the transfer function calculated can be:
Voltage gain: Input voltage source and output expression = V(OUT)
Current gain: Input current source and output expression = I(RL)
Transconductance: Input voltage source and output expression = I(RL)
Transadmittance: Input current source and output expression = V(OUT)
This analysis mode also calculates the small-signal input and output impedances.