On Thu, Oct 31, 2019 at 11:31 AM, Raymond Domp Frank wrote:
That should never happen; it's a problem in your IC or circuit. Vbat should
*never* source a current.
OK I just checked my OTHER unit. I got it weeks after the first one and from a different supplier. Same diode installed - no problems with the unit whatsoever calibrates and works great.
With unit OFF (USB NOT plugged in)
Actual V at battery terminals = 4.17 V
Actual voltage at cathode of diode = 4.13V
About the same Vdrop across the diode with power unplugged, checked with the Rigol in diode check mode.
So, there you have it. I'm going to take a break Raymond because I have other things to do. I thank you for working along but I do not think you are correct in your analysis (neither am I) . I think others may want to try and play along or explain what the observations are. I will check in later and see if I can add any more to it. But again I do not think we understand this circuit in toto. I've learned in life if the facts don't fit your understanding, then you may need to change your understanding. Talk to you guys later today.
