I'm using ADG601 as shown in the image above. When I provide an high value to SHDN i can correctly see VBatt = +VH. On the other hand, when I provide a low value to SHDN i can not see +VH = 0 V.
Can someone help me in understand why?
Thank you very much.
Hi, Matteo Colombo.
I have a few questions before I can evaluate the ADG601 performance:
You might want to check these points first so we can ensure that your application set-up is valid.
thank you very much for your reply. The answers to your questions are listed here:
1. Vbatt = 3.3V
2. with SHDN low I see +VH = 2.53 V
3. +VH is connected to 6 switches to provide them positive power supply (2 ADG1408 and 4 ADG1404)
4. the low value provided to SHDN is 0V.
Is it possible to have a scope shot showing your results? Can you place the scope probes on the nodes VBatt, SHDN, and +VH? IT would be better if you could show the result when you toggle the SHDN node to logic 0.
Another question would be, what is your power-up sequence? Does SHDN goes before Vbatt is being provided in the system?
Also, it seems that you are trying to power-up the ADG1408 and ADG1404 at 3.3V. Please have a look at the Power Requirement Table of the Specifications Section of the respective datasheets, it is stated that the ADG1404/08 are operational from 5V to 16.5V in single supply rail. See figures below.
So if +VH = 3.3V only, it will not power-up the ADG1404 and ADG1408s.
You might want to have a look at these points too.