Features and Benefits
- Complete Linear Charger Controller for 2-Cell Lithium-Ion Batteries
- 1% Voltage Accuracy
- Programmable Charge Current
- C/10 Charge Current Detection Output
- Programmable Charge Termination Timer
- Space Saving 8-Pin MSOP Package
- Automatic Sleep Mode When Input Supply is Removed (15µA Battery Drain)
- Automatic Trickle Charging of Low Voltage Cells
- Programmable for Constant-Current-Only Mode
The LTC1731-8.2/LTC1731-8.4 are complete constant-current/constant-voltage linear charger controllers for 2-cell lithium-ion (Li-Ion)batteries. Nickel-cadmium (NiCd) and nickel-metal-hydride (NiMH) batteries can also be charged with constant current using external termination. The external sense resistor sets the charge current with 7% accuracy. An internal resistor divider and precision reference set the final float potential with 1% accuracy. The output float voltages are set internally to 8.2V (LTC1731-8.2) or 8.4V (LTC1731-8.4).
When the input supply is removed, the LTC1731-8.2/LTC1731-8.4 automatically enter a low current sleep mode, dropping the battery drain current to typically 15µA. An internal comparator detects the end-of-charge (C/10) condition while a programmable timer, using an external capacitor, sets the total charge time. Fully discharged cells are automatically trickle charged at 10% of the programmed current until battery voltage exceeds 4.95V.
The LTC1731-8.2/LTC1731-8.4 are available in the 8-pin MSOP and SO packages. For 1-cell Li-Ion battery charging, see the LTC1731-4.1 and LTC1731-4.2 data sheets.
| Float Voltage
- Cellular Phones
- Handheld Computers
- Charging Docks and Cradles
- Programmable Current Source
Product Lifecycle Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
Sample & Buy
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