2S Li-ion Battery Protection Board (Code 19) — Product Introduction

Overview

This protection board features the PWCHIP PW7120 protection IC and two PW4406A MOSFETs, delivering complete overcharge, over-discharge, overcurrent, and short-circuit protection for 2S lithium-ion battery packs (7.4 V nominal, 8.4 V fully charged). The continuous discharge current is 3 A, and the overcurrent protection threshold is approximately 7 A. The integrated PW4242 asynchronous buck charger supports DC input from 10 V to 24 V and provides up to 2 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	DC 10 V–24 V
Charging IC	PW4242
Charging Topology	Asynchronous buck charging
Battery-Side Charging Current	2 A

Key ICs

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

PW4242 is an asynchronous switching buck charger with conversion efficiency up to 90 %. It accepts 10 V–24 V input and steps it down to 8.4 V at 0.5 A–2 A for charging 2S battery packs.

Key Features

· Protection and charging combined on one board

· PW4242 asynchronous buck charging supports 10 V–24 V wide-range input

· Compatible with 12 V, 15 V, 20 V, and 24 V adapters

· 2 A charge current, suitable for medium-capacity battery packs

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

· Ideal for 2S battery packs powered by wide-voltage DC supplies

Schematic

Code 19 Schematic

PCB Photo

Code 19 PCB Photo

Typical Applications

Industrial equipment, security monitoring, in-vehicle devices, solar power systems, power tools.

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.