GENERAL DESCRIPTION

The SGM41524 is a compact and efficient Lithium ion (Li+) or Lithium ion polymer (Li+/polymer) battery charger. It can provide power and charge the single cell battery of a system typically found in compact portable device. An internal switching buck converter regulates the supply input for charging the battery and powering the system even if the battery is absent. The converter can also operate as a simple pass-through switch with no switching if the load and input voltages are close.

A typical application circuit is shown in Figure 2. The SGM41524 features resistor programmable constant current and constant voltage charging capability plus a charge limiting timer and operates in compliance with the BAJ/JEITA safety guide. An NTC (β = 3950K) can be used for battery temperature sensing on top of the internal junction temperature monitoring. The IND status output pin can be connected to LEDs to indicate the operating conditions, such as power input ok (POK), in charging (CHG), VIN over-voltage (POK and CHG alternate blinking) and no power/disabled (OFF). Voltage fold-back on the output is provided to power the system from the input while retaining battery charge and preventing overcharge. Input under-voltage regulation is implemented by reducing the load current such that VIN stays above a minimum when the source is weak. Similarly, the die temperature can be regulated and limited by reducing output power to avoid device or the circuit board being overheated.

These features simplify the system design and ensure safe and reliable operation as well as improved user experience.

The SGM41524 is delivered in a Green TDFN-2×3-8BL package. The device operates in -40℃ to +85℃ with two thermal regulation options for +55℃ or for +115℃.

FEATURES

● Constant Current, Constant Voltage (CCCV) Charging with Floating Time-Out Timer

● Constant Current Pre-charge

● Maximum 2.3A Charging for 4.2V to 4.5V Battery

● 1.34MHz Switching Frequency

● Programmable Charge Voltage and Current

● 4.15V Input Voltage Regulation

● Output Voltage Fold-Back Charge Retaining

● Thermal Regulation Options

? SGM41524: +115℃

? SGM41524C: +55℃

● Typical Peak Efficiency of 92 at 1.5A, VIN = 5V

● -40℃ to +85℃ Operating Temperature Range

● Available in a Green TDFN-2×3-8BL Package

APPLICATIONS

Powering and Charge Control of Systems with 500mAh to 6000mAh Li+/Polymer Batteries