Part Number: LM66100
Hello,
I am designing a new battery powered circuit and I need some protections on the battery connection. The battery will be a 3.6V primary lithium battery (lithium thionyl chloride).
The problem is that the battery can be changed while the system is deployed, so I want to avoid risks such polarity inversion and ESD.
My idea is to use LM66100 to protect from polarity inversion, a TVS diode for ESD (the 2 kV ESD protection on LM66100 could not be enough...) and a polyswitch to be sure that the battery does not explode when there is some fault (TVS diodes fail short). LM66100 will be always on (CE = 0). Moreover, I have to place the current sense resistor for BQ35100.
The problem is how to place all those parts. I think I should place devices this way:
But there is something not clear to me. In the case of, say, a 6 kV ESD event on the battery terminals, the TVS can dissipate power and solve the problem. But what would happen to LM66100? Could it be broken for such an event?
In general, how can I take into account the 6 V absolute maximum input voltage rate of LM66100? Perhaps shoould I move LM66100 after all devices? But this way I am not sure it can protect the circuit from battery polarity inversion.
My main goal is to have the least possible leakage from all those devices, hence I have to choose a low leakage TVS diode and a low resistance polyswitch, but how can I choose the other parameters?
Can you please give some advices about that?
Thanks in advance and best regards
Stefano