Tool/software: TINA-TI or Spice Models
Dear all,
This Robin Liu, FAE from STL3472.TSChenzhen. Now our customer use TL347x as single supply op-amp to amplifier the 0~200mV voltage input, the tl3472 datasheet say the common mode input voltage is 0 to 2.8V when single +5V supply ,but the TI-TINA simulation result is the output can’t follow the input, so can you provide some comments for this? Thanks.
Thanks & Best regards
Robin Liu | FAE
Robin,
The issue is easier to see in a DC transfer curve, VOUT vs. VIN
The model is trying to do you a favor by being pessimistic about the VOL and VOH on this device.
There is no VOL chart in the data sheet to know the real VOL perfomance. The schematic in the data sheet suggest an anti saturation for the NPN collector sink driver. Therefore I would expect about 0.1V for VOL in the application.
For a 5V supply there are many other devices available that would provides a wider output range that includes zero.
What are the key parameters needed?
Robin,
I found a VOL test from the past. I was right, VOL is about 0.1V with no to little load.
Robin,
The model is too simple. About 30 lines in device macro.
Here is simulation IOL/VOL model. Compare this to device data on Dec 7 post.
