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Battery & Power Management

Chargers, protection ICs, and fuel gauges: termination behavior, load-sharing, and safety pins that cheap modules leave out.

Written and verified by John Merton · verified 2026-07-10

Battery and power management ICs handle the boundary between a rechargeable cell and the rest of the board. This category covers linear chargers like the TP4056 and MCP73831, protection ICs, and power-path management. The gotcha that recurs across every part in this category is shared: the charger IC is not a power supply, and the battery is not a stiff rail. A charger plus a battery plus a load on the same net is a three-body problem, and the solution is either a load-sharing circuit or a power-path manager.

How to choose

The axes below are the criteria you actually weigh when selecting a part in this category.

Charge current programmability and termination behavior
Most linear chargers set charge current with a single resistor. Termination thresholds — when the charger decides the battery is full — differ between parts and can leave a battery at 90% if the threshold is too conservative.
See:TP4056MCP73831BQ24074
Load sharing vs direct battery connection
A charger connected to a battery and a load on the same net confuses charge termination. A load-sharing circuit or a power-path charger separates the charge path from the load path.
See:TP4056MCP73831BQ24074
Safety pins: thermistor, enable, power-good
The pins that cheap modules leave floating — thermistor, enable, power-good — exist to prevent charging a frozen or over-temperature battery. Floating them disables those protections silently.
See:TP4056MCP73831BQ24074

All parts in this category

Compare specs

Parts in this guide verified against manufacturer datasheets; latest 2026-07-10.

MPNPackageLifecycleHeadline spec
TP4056ESOP-8 (bottom heat-sink pad)ActiveInput range: VCC 4.0 V min / 5 V typ / 8.0 V max (operating); absolute max VCC 8 V
MCP73831SOT-23-5ActiveVDD range: 3.75 V to 6 V (UVLO start 3.45 V typ rising)
BQ24074VQFN-16 (TI package code RGT), 3.00 mm × 3.00 mmActiveInput voltage range (IN): 4.35-10.2 V operating (BQ24074; '72/'73/'75/'79 grades: 4.35-6.4 V); IN voltage range 4.35-26 V; absolute maximum IN -0.3 to 28 V

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