Why would I use a STM704 instead of a STM806 battery monitor?

[TRose.6]

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[Peter BENSCH]

Welcome, @Terry Rose​, to the community!

The differences between STM704 and STM806 are indeed not listed on the first page of the data sheet, but can be found after a close look at the parameter tables:

• VPFI (Power-fail comparator, data sheet, pg. 33)
  • STM704: 1.237V±2%
  • STM806: 1.237V±4%
• VRST (Reset thresholds, data sheet, pg. 34)

So to answer your question, the cheaper STM806 is the one to use if you have lower accuracy requirements.

Hope that helps?

Regards

/Peter