LM3150: LM3150 : PSPICE simulation.

Nikhil Anjane1

Part Number: LM3150

Hi,

I am trying to simulate the ciruit diagram for LM3150 IC in PSPICE. I used the LM3150 Transient model already available in the PSPICE.

When I simulate the circuit. I can see that the Vcc pin has 6V, whereas the LG pin of the IC is at just 100mv constantly and thus my output voltages and current are improper.

According to the datasheet the output of the LG pin should be same as Vcc, and as the LG pin is a direct output from the IC I guess there is some issue in the model.

Can anybody help me fix this issue?

over 5 years ago

0 Marshall_Beck over 5 years ago

TI__Mastermind 35210 points

LG is gate drive for low side.

My suspicion is the circuit needs revised in the simulation.

If the controller never tells the low side to turn on, that tells me it is not sensing the output voltage. What is the HG pin reading?

I would confirm that feedback divider is correctly hooked up to IC net, FB.

0 Nikhil Anjane over 5 years ago in reply to Marshall_Beck

Prodigy 90 points

Hi Marshall,
The HG pin reading is 12V which is same as that of Vin.

Regards,
Nikhil

0 Marshall_Beck over 5 years ago in reply to Nikhil Anjane

TI__Mastermind 35210 points

You are not sensing the output voltage.

You are operating in maximum duty cycle.

Please confirm schematic entry.

0 Nikhil Anjane1 over 5 years ago in reply to Marshall_Beck

Prodigy 165 points

Hi Marshall,

I have attached my PSPICE project file. I would be a lot help if you have a look at it and guide me.
I am sensing the feedback but that also remains constant at 12V.

Regards,
Nikhil