Features and Benefits
- Low Profile (1mm) ThinSOT™ Package
- Programmable Charge Current: 50mA to 180mA
- No Blocking Diode Required
- No Sense Resistor Required
- 1% Accurate Preset Voltage: 4.2V
- Charge Current Monitor Output for Charge Termination
- Automatic Sleep Mode with Input Supply Removal
- Manual Shutdown
- Negligible Battery Drain Current in Shutdown
- Undervoltage Lockout
- Self Protection for Overcurrent/Overtemperature
The LTC1734L is a low cost, single cell, constant-current/constant-voltage Li-Ion battery charger controller. When combined with a few external components, the SOT-23 package forms a very small, low cost charger for single cell lithium-ion batteries. The LTC1734L is a lower charge current version of the LTC1734.
The LTC1734L provides a fixed float voltage of 4.2V with 1% accuracy (for 4.1V and 4.15V float voltages, contact Analog Devices Marketing). Constant current is programmed using a single external resistor between the PROG pin and ground. Manual shutdown is accomplished by floating the program resistor while removing input power automatically puts the LTC1734L into a sleep mode. Both the shutdown and sleep modes drain near zero current from the battery.
Charge current can be monitored via the voltage on the PROG pin allowing a microcontroller or ADC to read the current and determine when to terminate the charge cycle. The output driver is both current limited and thermally protected to prevent the LTC1734L from operating outside of safe limits. No external blocking diode is required.
The LTC1734L can also function as a general purpose current source or as a current source for charging nickel-cadmium (NiCd) and nickel-metal-hydride (NiMH) batteries using external termination.
|Charge Current||V float|
|LTC1734||180mA to 700mA||4.1V or 4.2V|
|LTC1734L||50mA to 180mA||4.2V|
- Cellular Telephones
- Handheld Computers
- Digital Cameras
- Charging Docks and Cradles
- Low Cost and Small Size Chargers
- Programmable Current Sources
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.
Tools & Simulations
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:
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.