Other Parts Discussed in Thread: TPS25940
I have redundant batteries, each with its own BQ25792. In some cases, VSYS of one charger can see power from the other battery or charger. It appears that the BQ25792 does not properly regulate the final charge voltage in this case.
See register dump below. VBAT is at 8.44V, VREG is 8.2V, but the battery is still charging at 547mA from the 8.5V at VSYS. PFM is disabled in reg 12.
Is the device unable to regulate charge voltage if the converter isn't needed because power is present at VSYS?
State: TCV
VSYSMIN 00: 7000 VINDPM 05: 3600 PCHG 08:04
VREG 01: 8200 IINDPM 06: 1250 TERM 09:01
ICHG 03: 4200 VOTG 0B: 2800 RCHG 0A:63
IOTG 0D:03 TIMR 0E:3D
Chg 0 0F:A2 Chg 0 1B:0F TEMP 16:C0
Ctl 1 10:00 Sts 1 1C:90 NTC0 17:7A
2 11:00 2 1D:01 NTC1 18:01
3 12:30 3 1E:00 ICO 19:00
4 13:29 4 1F:00
5 14:24
Flt 0 20:00 00 Flt 0 26:00 00 Flt 0 2C:00
Sts 1 21:00 00 Flg 1 27:00 00 Msk 1 2D:00
Chg 0 22:00 00 Chg 0 28:00
Flg 1 23:00 00 Msk 1 29:00 Adc 2E:B8
2 24:00 00 2 2A:00 2F:00
3 25:00 00 3 2B:00 30:00
IBUS 31: 12 IBAT 33: 547 TS 3F: 0
VBUS 35:12109 VBAT 3B: 8443 TDIE 41: 65
VAC1 37:12112 VSYS 3D: 8503 D+ 43: 0
VAC2 39:12112 D- 45: 0
DPDM 47:00 Part 48:08 -108 err
