2S Li-ion Battery Protection Board (Code 16) — Product Introduction

Overview

This protection board uses the PWCHIP PW7120 protection IC together with two PW4406A MOSFETs to deliver complete overcharge, over-discharge, overcurrent, and short-circuit protection for 2S lithium-ion battery packs (7.4 V nominal, 8.4 V fully charged). It supports a 3 A continuous discharge current with an approximately 7 A overcurrent protection threshold. The integrated PW4253 synchronous boost charger supports 5 V / 3 A USB input and provides up to 1.7 A charge current to the battery.

Specifications

Parameter	Specification
Battery Type	2S (2-series Li-ion, 7.4 V nominal, 8.4 V fully charged)
Continuous Discharge Current	3 A
Overcurrent Protection Threshold	Approx. 7 A
Protection IC	PW7120
MOSFETs	PW4406A × 2
MOSFET Package	SOP-8
Charging Input	USB 5 V / 3 A
Charging IC	PW4253
Charging Topology	Synchronous boost charging
Battery-Side Charging Current	1.7 A

Key ICs

PW7120 is a dedicated 2-cell lithium-ion protection IC integrating overcharge, over-discharge, overcurrent, and short-circuit protection. It features a simple external circuit and low power consumption.

PW4253 is a synchronous switching boost charger with conversion efficiency up to 95 %. It is suitable for 5 V USB input boosted to 8.4 V at 1 A–2 A. The IC integrates input OVP, disabling charging when the input exceeds 6 V, and supports input voltages up to 18 V.

Key Features

· Single-board protection plus charging solution

· PW4253 synchronous boost charging with up to 95 % efficiency

· 5 V USB input boosted to 8.4 V, delivering 1.7 A charge current

· Integrated 6 V OVP shutdown and 18 V input withstand

· PW7120 protection IC plus two PW4406A MOSFETs for 7 A overcurrent protection

· Suitable for 2S battery packs requiring high-current USB charging

Schematic

Code 16 Schematic

PCB Photo

Code 16 PCB Photo

Typical Applications

Bluetooth speakers, portable fans, LED lighting, small power tools, USB-charged products.

Wiring Notes

Connect the battery as indicated on the schematic. The charge/discharge terminals are P+ and P-.

Documentation & Technical Support

We provide chip samples, technical documentation, and circuit design support. For more information or to request materials, please contact us at support@pwchip.com or reach an authorized distributor at https://www.pwchip.com/page/180.html.