Other Parts Discussed in Thread: TIDA-00720
I have a question regarding the defined VIH for the DONE pin which is according to the datasheet 0.7xVDD. In the intended use cases (drive the EN pin of an LDO or DC/DC converter) this threshold is problematic. In my case I want to drive the EN pin of a DC/DC converter that buck converts 4.2V to 1.8V. According to the datasheet I would need level translation from the MCUs 1.8V to at least 2.94V to drive the DONE pin of the TPL5111.
Interestingly in your power cycling reference design (TI Design TIDA-00720) you drive the DONE pin with 1.8V while Vin is 4.5V according to your scope measurements on page 10.
So is that an oversight in the reference design and it would not work relieably or is the VIH threshold in the datasheet too conservative and would driving the DONE pin with 1.8V with VCC at 4.2V always work?
Daniel
