Ideal for short-circuit protection of metal-cased batteries
- Nch High-side Protection
A standardized ground level simplifies the system design - Triple step-up circuit
Reduces the on-resistance of FETs and suppresses heat generation during charging - High-accuracy overcurrent/overcharge protection
Maximizes battery performance without compromising safety - Power-saving pin
Prevents zero battery charge and deep discharge - NTC thermistor connection pin
Achieves overheating protection function
Nch MOSFET High-side
Battery Protection IC for 1-cell Pack
S-821A/1B Series
Nch high-side protection ensures the safety and reliability of metal-cased batteries
A standardized ground level simplifies the system design
There is a growing demand for metal-cased batteries with high energy density, particularly for smartwatches and smartphones.
The S-821A/1B Series is an IC that can provide Nch high-side protection, which is necessary for short-circuit protection in metal-cased batteries.
By placing the Nch MOSFETs, which control charging and discharging, on the positive side (high-side) of the lithium battery, the ground levels of the battery pack and system can reach the same voltage, contributing to a simplified system design.
A triple step-up circuit suppresses heat generation during charging
The S-821A/1B Series has an internal triple boost charge pump, which can increase the drive voltage of the Nch MOSFET.
This reduces the on-resistance, suppressing the heat generated by the MOSFET and improving safety during charging.
Maximizes battery performance without compromising safety
The S-821A/1B Series has three levels of discharge overcurrent protection, and the accuracy of each level is considered top-class in the industry*1, *2. Furthermore, the overcharge detection voltage accuracy of ±15mV is also recognized as top-class within the industry*1.
This allows the battery performance to be maximized, such as charging capacity and usage time, without compromising the safety of the battery pack.
Furthermore, the package is available in the compact WLP-8V (1.52 × 1.08 × t0.35 (max.) mm) and the SNT-8A (2.46 × 1.97 × t0.5 (max.) mm) with outer leads, which are easily mountable, allowing you to choose the one that best suits your application.
*1 As a 1-cell battery protection IC.
Based on our research as of October 2024.
*2 S-821B Series
Prevents zero battery charge and deep discharge
The S-821A/1B Series is equipped with a power-saving input pin (PS pin), which can activate a power-saving function with an external signal, enabling it to stop the discharge of the battery.
At the same time, the power-saving function can suppress the current consumption of the protection IC to 50nA max.
When the product is not used during the period of stock, it prolongs the period until the battery runs out of power, protecting it from deep discharge and strengthening the safety of the product.
Achieves overheating protection function by connecting an NTC thermistor
Overheating protection can be achieved by connecting an NTC thermistor to the S-821A/1B Series. By using an NTC thermistor with a resistance of 100kΩ or 470kΩ, temperatures from +65°C to +85°C can be detected. This improves battery safety and prevents malfunctions and problems caused by overheating.
Applications
Lithium-ion Battery Protection ICs Lineup
Specifications
Product Name | S-821A | S-821B | |
---|---|---|---|
For general-use | |||
Number of cells | 1-cell | ||
Overcharge detection voltage (Accuracy) | 3.50V to 4.80V (±15mV) | ||
Overdischarge detection voltage (Accuracy) | 2.00V to 3.00V (±50mV) | ||
Discharge overcurrent 1 detection voltage (Accuracy) | -0.003V to -0.100V (±1mV) |
-0.003V to -0.100V (±0.75mV) |
|
Discharge overcurrent 2 detection voltage (Accuracy) | -0.006V to -0.100V (±3mV) |
-0.006V to -0.100V (±2mV) |
|
Load short-circuiting detection voltage (Accuracy) | -0.020V to -0.100V (±5mV) |
-0.020V to -0.100V (±4mV) |
|
Charge overcurrent detection voltage (Accuracy) | 0.003V to 0.100V (±1mV) |
0.003V to 0.100V (±0.75mV) |
|
Current consumption | During operation | 6.0μA typ., 10μA max. (Ta = +25°C) | |
During power-down | 50nA max. (Ta = +25°C) | ||
During power-saving | 50nA max. (Ta = +25°C) | ||
Package | SNT-8A, WLP-8V | ||
Operation temperature range | Ta= -40°C to +85°C | ||
Datasheet |