LT1498 or RH1498 Simulation model?

Question

Hello, 
 Looking at a design that uses the RH1498 in a non-standard way. The design is relying on the current limited output capability. When using the LT1498 in a PSPICE simulation, the simulation shows the OP-AMP output going into the current-limit output, but the power dissipation of the OP-AMP does not correlated with the power supply current measurements. In the simulation I see the output current of the OP-AMP is about 38mA, yet both the positive and negative supply currents are less than 3mA each. Does the PSPICE model not work for the current limited output condition? And why does the power dissipation show -465mW?

Hooman · Accepted Answer

Hi EAL, 
 If I pull up the LT1498 Example circuit in LTspice and simulate with a heavy resistive load, I see that the supply current does reflect the heavy load at output. Looks like you're seeing something different. 
 In this example shown, a heavy Rload (2ohm) is drawing close to 25mA at the output and the supply current I(V1) is around 28mA. So, it seems like there is tracking. 
 
 Here is the simulation file itself: 
 LT1498 supply current EZ 3_7_22.asc 
 Maybe you can share your LTspice asc file to show the issue you're having. 
 
 Regards, 
 Hooman)

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LT1498 or RH1498 Simulation model?