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bobspam@free.fr
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DA14683 Fuel Gauge

Hello

I wish to replace the 0.1 Ohm resistor used to measure power consumption by the DA1468x by an externally driven N-Channel MOSFET.
For instance DMN6140 has a 0.14 Ohm internal resistance.

- Does the fuel gauge can support a N-Channel MOSFET instead of the 0.1 Ohm resistor (0.14 Ohm) ?
- Does the fuel gauge support the "switched-off state" (considering that the mosfet will cut power of vbat)

Thank you in advance

Device: 
bobspam@free.fr
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Last seen: 2 weeks 4 days ago
Joined: 2018-06-20 08:07
IRLML2030 has 0.1 Ohm

IRLML2030 has 0.1 Ohm internal resistance.

Could this work ?

PM_Dialog
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Joined: 2018-02-08 11:03
Hi bobspam@free.fr,

Hi bobspam@free.fr,

The DA1468x can support other SOC resistor values. Although the FET ON resistance is not a constant, so I suppose that the fuel gauge measurements will not be very accurate. Regarding the switching off the FET, it is strongly NOT recommended to do that because it is too risky. The risk is that Vbat voltage will be present on the SOC pins, and they are only allowed for +0.1V and -0.1V.  If it also cuts off the battery, then maybe it could work but it is not suggested.

Thanks, PM_Dialog