High voltage, high current controller for battery charging

Linear Technology Corp.'s LTC4000-1 is a high-voltage, high-performance controller that converts many externally compensated dc/dc power supplies into full-featured battery chargers with maximum power point control. In contrast to the LTC4000, the LTC4000-1 has an input voltage regulation loop instead of the input current regulation loop.

Features of the LTC4000-1’s battery charger include: Accurate (±0.25%) programmable float voltage, selectable timer or current termination, temperature qualified charging using an NTC thermistor, automatic recharge, C/10 trickle charge for deeply discharged cells, bad battery detection, and status indicator outputs. The battery charger also includes precision current sensing that allows lower sense voltages for high current applications.

The LTC4000-1 supports intelligent PowerPath control. An external PFET provides low loss reverse current protection. Another external PFET provides low loss charging or discharging of the battery. This second PFET also facilitates an instant-on feature that provides immediate downstream system power even when connected to a heavily discharged or shorted battery. The LTC4000-1 is available in low profile, 28-lead, 4 × 5 mm QFN and SSOP packages.

Applications include:

• Solar Powered Battery Charger Systems
• Battery Charger with High Impedance Input Source, e.g., Fuel Cell or Wind Turbine
• Battery Equipped Industrial or Portable Military Equipments

Features of the LTC4000-1:

• Maximum Power Control: Solar Panel Input Compatible
• Complete High Performance Battery Charger When Paired with a dc/dc Converter
• Wide Input and Output Voltage Range: 3 to 60 V
• Input Ideal Diode for Low Loss Reverse Blocking and Load Sharing
• Output Ideal Diode for Low Loss PowerPath and Load Sharing with the Battery
• Programmable Charge Current: ±1% Accuracy
• ±0.25% Accurate Programmable Float Voltage
• Programmable C/X or Timer Based Charge Termination
• NTC Input for Temperature Qualified Charging
• 28-Lead 4 × 5 mm QFN or SSOP Packages

For more information, contact Linear Technology Corp., 1630 McCarthy Blvd., Milpitas, CA 95035. Phone: (408) 432-1900.