Features and Benefits
- General Purpose Battery Charger Controller
- Efficient 550kHz Synchronous Buck PWM Topology
- ±0.5% Output Float Voltage Accuracy
- Programmable Charge Current: 4% Accuracy
- Programmable AC Adapter Current Limit: 3% Accuracy
- No Audible Noise with Ceramic Capacitors
- INFET Low Loss Ideal Diode PowerPath™ Control
- Wide Input Voltage Range: 6V to 28V
- Wide Output Voltage Range: 2V to 28V
- Indicator Outputs for AC Adapter Present, Charging, C/10 Current Detection and Input Current Limiting
- Analog Charge Current Monitor
- Micropower Shutdown
- 20-Pin 4mm × 4mm × 0.75mm QFN Package
The LTC4012 is a constant-current /constant-voltage battery charger controller. It uses a synchronous quasi-constant frequency PWM control architecture that will not generate audible noise with ceramic bulk capacitors. Charge current is set by external resistors and can be monitored as an output voltage. With no built-in termination, the LTC4012 family charges a wide range of batteries under external control.
The LTC4012 features fully adjustable output voltage, while the LTC4012-1 and LTC4012-2 can be pin-programmed for Lithium-Ion/Polymer battery packs of 1-, 2-, 3- or 4-series cells. The LTC4012-1 provides output voltage of 4.1V/cell and the LTC4012-2 is a 4.2V/cell version.
The device includes AC adapter input current limiting, which maximizes charge rate for a fixed input power level. An external sense resistor programs the input current limit, and the ICL status pin indicates reduced charge current as a result of AC adapter current limiting. Ideal diode control at the adaptor input improves charger efficiency.
The CHRG status pin is active during all charging modes, including special indication for low charge current.
|Vfloat||Vfloat Range||/ACP Pin|
|LTC4012-1||4.1V||1-4 Li-Ion Cells||Yes|
|LTC4012-2||4.2V||1-4 Li-Ion Cells||Yes|
- Notebook Computers
- Portable Instruments
- Battery Backup Systems
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.
Evaluation Kits (2)
Demonstration circuit 1614 features the LTC4012CUF, a multi-chemistry single battery charger controller with PowerPath™ control. The input supply voltage is 13.5V to 20V and is initially configured for a current limit of 10A. The charger float voltage is programmed by jumpers to support 1- to 4- series cells of both Li-Ion/Polymer and Li-iron phosphate (LiFePO4) at 4.2V/cell and 3.6V/cell, for a total of eight settings. The demo board is initially configured for constant-voltage charging of a 12.6V Li-Ion/ Polymer battery and constant-current charging at 8A, though current derating may be necessary due to certain operating conditions.
Demonstration circuit DC1256A is a single-battery standalone battery charger that can support any version ofthe LTC4012 family of parts. The LTC4012 family of charge controller IC’s do not support charge termination for any specific battery chemistry. Any charger termination, if necessary, is accomplished outside the LTC4012 with the most common method using a microcontroller. The DC1256A is shipped with the LTC4012-2 installed,which is optimized for Li-ion charge applications using a 4.2V/cell float voltage.The charger output voltage is programmed by jumpers to support 1, 2, 3 and 4 series stack Li-ion batteries. The input voltage is can be between 6V and 20V with the maximum voltage of the Demo Board design limited by the input capacitor voltage ratings. To reach full charge,the minimum input voltage must be greater than the float voltage setting.
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
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.