Overview
Features and Benefits
- Simple Charging of Li-Ion, NiMH and NiCd Batteries
- Very High Efficiency: Up to 97%
- Precision 0.5% Charging Voltage Accuracy
- Preset Battery Voltages: 12.3V, 12.6V, 16.4V and 16.8V
- 5% Charging Current Accuracy
- Charging Current Programmed by Resistor or DAC
- 0.5V Dropout Voltage, Duty Cycle > 99.5%
- AC Adapter Current Limit* Maximizes Charging Rate
- Flag Indicates Li-Ion Charge Completion
- Auto Shutdown with Adapter Removal
- Only 10µA Battery Drain When Idle
- Synchronizable Up to 280kHz
Product Details
The LT1505 PWM battery charger controller fast charges multiple battery chemistries including lithium-ion (Li-Ion), nickel-metal-hydride (NiMH) and nickel-cadmium (NiCd) using constant-current or constant-voltage control. Maximum current can be easily programmed by resistors or a DAC. The constant-voltage output can be selected for 3 or 4 series Li-Ion cells with 0.5% accuracy.
A third control loop limits the current drawn from the AC adapter during charging*. This allows simultaneous operation of the equipment and fast battery charging without overloading the AC adapter.
The LT1505 can charge batteries ranging from 2.5V to 20V with dropout voltage as low as 0.5V. Synchronous N-channel FETs switching at 200kHz give high efficiency and allow small inductor size. A diode is not required in series with the battery because the charger automatically enters a 10µA sleep mode when the wall adapter is unplugged. A logic output indicates Li-Ion full charge when current drops to 20% of the programmed value.
The LT1505 is available in a 28-pin SSOP package.
Applications
- Notebook Computers
- Portable Instruments
- Chargers for Li-Ion, NiMH, NiCd and Lead Acid Rechargeable Batteries
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)
Documentation
Reliability Data (1)
Application Notes (1)
Tools & Simulations
LTspice
LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.

Models for the following parts are available in LTspice:
Product Recommendations
LT1505 Companion Parts
Recommended Related Parts
Reference Materials
Design Resources
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.
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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.