LTspice syntax problem

[Flyback]

Hi,
How do i make the time of a "Pulse" source equal to the voltage of a node in LTspice?
The attached LTspice wont work. Do you know how to solve?

 

[Papabravo]

It is unlikely that you will be able to do what you want in that way. The fields in the pulse source must be numbers or parameters that can be resolved into a number BEFORE the beginning of the simulation. If you are trying to create a PWM signal with a fixed frequency and a variable duty cycle that will respond to a control voltage, there are better ways to accomplish that.

 

[alec_t]

You could use something like this, where the duty cycle varies with v(a) :-

 

[Tony Stewart]

I am an LTspice newbie and just learned how to do this

 

[Tony Stewart]

Using two interpolated pulses to make two sawtooths with 1000:1 T ratio = 10ms:10us compared with an arbitrary IF statement to make a PWM signal.

For those curious why I use Win7 x64 16GB instead of Win 10/11, it's because I like lean and fast on my 10 yr old PC.