USB powered lithium battery charger MAX1811

Photocoupler

Summary:

The MAX1811 is a USB-connected, single-cell Li-Ion battery charge controller that can be powered directly from the USB port or from another external power source with a supply voltage of +6.5V.

The MAX1811 requires no microprocessor control and the maximum charge voltage can be set to 4.1 V or 4.2 V with a maximum error of 0.5%.

The MAX1811's battery charge current can be set to 100mA or 500mA through a logic control circuit that meets USB current standards. The MAX1811 operates in a linear mode, eliminating the need for external inductors, and the built-in MOSFET power switch saves board size.

When using the U port power supply to charge the battery, for the low-power USB port, the potential of the SETI terminal of the MAX1811 chip should be pulled low, and the charging current is set to 100mA. For the high-power USB port, the SETI of the MAX1811 chip should be cited. The pin is connected to a high level, and the charging current is set to 500 mA; the 5ETV terminal is connected to a high level or connected to a low level, and the charging voltage of the lithium battery is set to 4.2 V or 4.1 V, respectively. The CHG terminal of the MAX1811 allows the chip to illuminate the LED during charging.

Application field

Cellular phone

Digital camera

Handheld computer

MP3 player

PDA and PDA

Two-way paging

characteristic

Charges Single-Cell Li+ Batteries Directly from USB Port

0.5% Overall Charging Accuracy

Minimal External Components

Input Diode Not Required

Automatic IC Thermal Regulation

Preconditions Near-Depleted Cells

Convenient Power SO-8 Package (1.4W)

Internal structure of the MAX1811

MAX1811 pin diagram

The MAX1811 data sheet can be found in the PDF document (click on the PDF file to download)