Other Parts Discussed in Thread: LM3880
We have had a TLV75801PDRVR fail in normal operation when configured as a 1.8V regulator in a production design. The fault presents as the regulator output sawtoothing between around 1V and Vin at at about 30Hz, independent of load, but with the bulk and HF decoupling capacitors in place.
Applying a burst of freezer specifically to the TLV785 chip restores correct operation, but only while the chip is still cold. As the freezer wears off, the device starts oscillating again around its correct output, with the peak output voltage eventually climbing almost to Vin, and the amplitude of the oscillation reducing to zero around the final d.c. level.
I have been looking for possible reasons for the failure. The TLV758 data sheet gives Absolute Maximum ratings for both the Vin and En inputs of 6.5V relative to ground. It also states that Vout must not be taken more than 300mV more positive than Vin.
These conditions are unconditionally met in our design, but is there any restriction not mentioned in the data sheet on the En high voltage being greater than Vin? This condition could briefly occur in our design during unscheduled removal of input power to the board.