I would like to have the rise and fall transition rate specification clarified. This item is found in the recommended operating conditions section and is defined as a max of 100ns/V. Can you verify that this is means, in my own words, that the transition time from low to high must be faster than 100ns/V? What will the part do (or not do) if the transition time is slower than 100ns/V?
The value shown in the datasheet is the MAXIMUM transistion time for the two input pins. It is probably easier to think of the reciprical of this value which would then be the MINIMUM slew rate for the input pins. The minimum slew rate is 1V/us. The slew rate must be higher than this in order for the device to recognize the input. If the slew rate is too slow then the device may not recognize the /MR or WDI inputs and issue false resets or no reset at all.
I was going to post a similar question on the TPS3801 until I found this post and reply.
I don't get it. These are power supply supervisors with reset. Why is the maximum input transition rise time 100 ns/V?
On page one of the data sheet under "typical application" it shows a push button switch going directly to MR. How can this possibly be 100 ns/V max? Its an input switch. Am I misinterpreting the data sheet?
Thanks,
Loren Hunt
Yes, the same answer applies to the TPS3801 as well.