SLVSCV5E March 2015 – December 2024 ATL431 , ATL432
PRODUCTION DATA
Slow or inaccurate responses can also occur when the reference pin is not provided enough overdrive voltage. This is the amount of voltage that is higher than the internal virtual reference. The internal virtual reference voltage will be within the range of 2.5V ± (0.5% or 1.0%) depending on which version is being used.
The more overdrive voltage provided, the faster the ATL43x responds.
For applications where ATL43x is being used as a comparator, it is best to set the trip point to greater than the positive expected error (that is, +1.0% for the A version). For fast response, setting the trip point to > 10% of the internal Vref should suffice. Figure 8-3 shows the transition from VOH to VOL based on the input voltage and can be used as a guide for selecting the overdrive voltage.
For minimal voltage drop or difference from Vin to the ref pin, TI recommends using an input resistor < 1MΩ to provide Iref.