PW7126 + PW4406A×4 3-Cell Li-ion Battery Charge-Discharge Protection Board Solution, Continuous 6A, Overcurrent Protection 7A
Product Details PCB Design Suggestions
3S Li-ion Battery Protection Board — Code 7
Overview
This protection board uses the proprietary PW7126 protection IC from Pingxin Micro, paired with two PW4406A MOSFETs. It provides complete over-charge, over-discharge, over-current, and short-circuit protection for 3S (three-cell series) Li-ion battery packs rated at 11.1 V nominal / 12.6 V fully charged. The board supports a continuous discharge current of 3 A, with an over-current protection threshold of approximately 4 A.
Specifications
|
Parameter |
Specification |
|
Battery Type |
3S (three-cell series Li-ion pack, 11.1 V nominal, 12.6 V fully charged) |
|
Continuous Discharge Current |
3 A |
|
Over-Current Protection Current |
Approx. 4 A |
|
Protection IC |
PW7126 |
|
MOSFET |
PW4406A × 2 |
|
MOSFET Package |
SOP8 |
|
Cell Balancing |
None |
|
Balancing IC |
None |
|
Board Dimensions |
To be confirmed |
Main Control IC
The PW7126 is a dedicated protection IC for 3-cell Li-ion batteries. It integrates over-charge, over-discharge, over-current, and short-circuit protection, and supports high-precision voltage detection.
Solution Highlights
· Two PW4406A MOSFETs provide 4 A over-current protection and 3 A continuous discharge.
· SOP8 package is easy to solder and cost-effective.
· PW7126 delivers high-precision voltage detection for accurate protection.
· Minimal external components reduce BOM cost.
· Ideal for low-power 3S Li-ion battery pack applications.
Circuit Schematic
Circuit Schematic
BOM (Bill of Materials)
|
No. |
Designator |
Model / Specification |
Qty |
|
1 |
CVC1 |
0603 1 µF / 16 V |
1 |
|
2 |
CVC2, CVC3 |
0603 0.1 µF / 16 V |
2 |
|
3 |
RSENSE |
1206 25 mΩ ±1 % |
1 |
|
4 |
RVC1, RVC2, RVC3 |
0603 1 kΩ ±1 % |
3 |
|
5 |
RVIN, RVM |
0603 2.21 kΩ ±1 % |
2 |
|
6 |
U1 |
PW7126 SOP8 |
1 |
|
7 |
U2, U3 |
PW4406A SOP8 |
2 |
Typical Applications
Bluetooth speakers, portable mini fans, small electric toys, LED light strings, and small instrumentation devices.
Wiring Instructions
Please wire the battery cells according to the labels shown in the schematic. The charge/discharge interface is P+ and P−.
Documentation & Technical Support
We provide chip samples, technical documentation, and circuit design support. For more solutions or to request materials, please contact us at support@pwchip.com or reach out through our distributor channel at https://www.pwchip.com/page/180.html.
