LM3485: TINA/SPICE model simulation - current sensing

Daniel Morris

Part Number: LM3485

Hi there,

I am using the SPICE model of the LM3485 in TINA. When I configure the circuit as shown in the datasheet (Figure 27, TINA circuit below), I get convergence errors when attempting to simulate the circuit.

However when I instead use a sense resistor (circuit below), I can simulate the circuit without any issues.

Is there any reason that I cannot simulate the first circuit configuration? Any help is greatly appreciated!

Kind regards,

Daniel

LM3485.TSC
LM3485_STARTUP.TSM

over 3 years ago

0 Daniel Li14 over 3 years ago

TI__Mastermind 27040 points

HI Daniel:

can you attached the first one simulation files so that we can check it.

due to it is TINA simulation issue, I am not sure whether it can be solved or not.

THanks

0 Daniel Morris over 3 years ago in reply to Daniel Li14

Prodigy 20 points

I've attached the first schematic (the one that doesn't converge), as well as the LM3485 SPICE macro I am using, to the original post.

Cheers,
Daniel

0 Daniel Li14 over 3 years ago in reply to Daniel Morris

TI__Mastermind 27040 points

HI Morris:

I check you schematic, I also can't simulated from TINA。 for Sense resistor ，I think you short Isen with Adj PIN, If you put sense resistor between Isen and Adj, from my result, it sitll not work.

I will suggest you can use Ti Pspice to do the simulation or you can directly test the EVM board.

Thanks

Daniel Li

Power management

Power management forum

LM3485: TINA/SPICE model simulation - current sensing