Anyone know how to do a transfer function in LTSpice?

Just as a quick circuit, I have connected a voltage ramp waveform to the base of an emitter follower. I want to plot the transfer function from base to emitter (then move on to move complex circuits later).

I have probed the base and the collector and have got transient analysis working quite happily. I cannot get the transfer function going though.

LTSPICE keeps spitting out the error: 'Transfer function source v not in circuit'.

Going back into the transfer function setup, I notice it has now changed my Vin reference to 'v'.

What am I doing wrong...?

All I want is a plot of Vin on the x axis and Vemitter on the Y axis.

Post the circuit diagram of the simulation.

Here it is...

Let me know your comments...

Thanks!

In some Spice simulators the Transfer Function is the S-plane Laplace transfer function, not the transient or DC transfer function. I suspect LTSpice may be the same.

If you are looking for a plot of input voltage versus output voltage, do a DC sweep (if LTSpice offers that function).

Look at the attached example

Here is an example. If you change the DC value of Vin, the transfer function will change.

Hi Mike and Ron

This is exactly what I am looking for. Thanks very much! I really appreciate it