Features and Benefits
- Complete Charger Controller for 3- or 4-Cell Lithium-Ion Batteries
- High Conversion Efficiency: Up to 96%
- Output Currents Exceeding 4A
- ±0.8% Charging Voltage Accuracy
- Built-In Charge Termination for Li-Ion Batteries
- AC Adapter Current Limiting Maximizes Charge Rate
- Thermistor Input for Temperature Qualified Charging
- Wide Input Voltage Range: 6V to 28V
- 0.5V Dropout Voltage; Maximum Duty Cycle: 98%
- Programmable Charge Current: ±4% Accuracy
- Indicator Outputs for Charging, C/10 Current Detection, AC Adapter Present, Low Battery, Input Current Limiting and Faults
- Charging Current Monitor Output
- Available in a 24-Pin Narrow SSOP Package
The LTC4007 is a complete constant-current/constant-voltage charger controller for 3- or 4-cell lithium-ion batteries. The PWM controller uses a synchronous, quasi-constant frequency, constant off-time architecture that will not generate audible noise even when using ceramic capacitors. Charging current is programmable to ±4% accuracy using a programming resistor. Charging current can also be monitored as a voltage across the programming resistor.
The output float voltage is pin programmed for cell count (3 cells or 4 cells) and chemistry (4.2V/4.1V). A timer, programmed by an external resistor, sets the charge termination time. Charging is automatically restarted when cell voltage falls below 3.9V/cell.
LTC4007 includes a thermistor input, which suspends charging if an unsafe temperature condition is detected. If the cell voltage is less than 2.5V, a low-battery indicator asserts and can be used to program a trickle charge current to safely charge depleted batteries. The FAULT pin is also asserted and charging terminates if the low-battery condition persists for more than 1/4 of the total charge time.
|Low battery threshold 4.2V cell||2.5V||3.25V|
|Low battery threshold 4.1V cell||2.44V||3.173V|
- Notebook Computers
- Portable Instruments
- Battery-Backup Systems
- Standalone Li-Ion Chargers
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 (1)
Demonstration circuit 498 is a single battery standalone battery charge controller with built in charge termination featuring the LTC4007. The input voltage is 13 to 20V. The charger output voltage is programmed by jumpers to support 3- and 4-Cell Li-ion batteries with a cell voltage of 4.1V or 4.2V/Cell. The maximum charge current is 4A. The demo board is initially configured for 12.6V Li-ion batteries. The board will automatically charge a battery to termination as soon as input power is applied with a battery connected prior to power up. Status LEDs are provided for CHG, ACP, FAULT, FLAG, ICL and LOBAT. An on-board NTC thermistor is provided.
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.