What Does This Module Do?
The 4S 4A Boost Charging Module is a dedicated voltage step-up charger for 4-cell series (4S) lithium-ion and LiPo battery packs. Its core function is straightforward but powerful: it accepts a low DC voltage between 3V and 6V at its input and amplifies it to a regulated 16.8V DC — the exact full-charge voltage required to safely top up four 3.7V lithium cells wired in series, producing a nominal 14.8V pack.
Two Ways to Power It
What sets the 4S 4A module apart for advanced builds is its dual input flexibility. You can power it through the onboard Type-C USB port using any 4A-capable adapter. Alternatively, for projects where a USB connection is not practical, an SMPS (switched-mode power supply) unit can be directly soldered onto the VIN and GND input pads, providing a stable, regulated DC source capable of the full 4A input demand. This makes the module equally at home on a workbench charging station as it is embedded inside a custom power system.
Built for Precision and Safety
The 1MHz switching frequency keeps the boost conversion tight and efficient. Quasi-CV mode actively compensates for the voltage drop caused by battery internal resistance and wiring resistance — so each of the four cells in the pack receives the correct charge voltage rather than an approximated figure. Protection circuits address overvoltage, short circuit at the battery terminals, and premature recharge triggering, all managed on-chip without external components.
Configurable for Other Pack Sizes
The back of the PCB carries clearly labelled solder pads for OUT (2S / 3S / 4S) and IN (1A / 2A / 4A). For this listing, the 4S and 4A pads are pre-selected. Should your project needs change, bridging the relevant pads reconfigures the same board for a different cell count or current level.
The compact 36mm × 18mm footprint and 4.38g weight make integration into tight enclosures straightforward, whether you are building a custom drone battery charger, power tool pack replenisher, or a portable multi-cell energy storage system.
Note: Always verify your Type-C adapter or SMPS unit is rated for sustained 4A output before connecting. Ensure all BAT and GND solder joints are clean and secure for stable operation at this current level.
Package Contents
1 × 4S 4A Type-C Boost Lithium Battery Charging Module
