MP2639A; VCC is too low

Battery Management
1

Hi team,

I tried to use the MP2639A for two-port application (charge and discharge) with two Li-Ion cells.

If charging voltage (5 V) is present at VL, VCC = 4.5 V, if no charging voltage is present (discharging), but only the battery voltage at VH (VH = 7.6 V), VCC = 120 mV. Without MID pin connected, VCC = 0V.

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Does anyone know, why VCC is not 4,5 V, if opperated with batterie?

2

Hi Stefan,
Please confirm if output VL is loaded when supplying from battery.

Best,
Nouman