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TINA/Spice/LMV324: Results of NTC thermisrtor control loop simulation using TINA

Part Number: LMV324
Other Parts Discussed in Thread: TINA-TI, LMV358, LMV358A

Tool/software: TINA-TI or Spice Models

Hi,

I have the attached circuit built to control a NTC thermistor to 100 Deg C. The thermistor is 1000 ohms at 25C and is small enough 200mw/C to heat up with 5V supplied. I am trying to determine if the circuit will work as it is.  The idea of the circuit is the LMV324V is used as a difference amplifier, keeping the thermistor at 75 ohms by controlling the FET to drive the bridge.

When I simulate it with TINA I get different results when I do a transient analysis, depending on the conditions. If I use "Calculate operating point it seems to work, When I use "Use 

initial conditions it oscillates and when I try "Zero initial conditions", I get a convergence problem and it doesn't simulate. My question is 2 fold, one, does the circuit look like it will work? and two, which condition should I use for simulation.

test_sch.pdf