LTC3550
LAST TIME BUYDual Input USB/AC Adapter Li-Ion Battery Charger with 600mA Buck Converter
- Part Models
- 2
- 1ku List Price
- Starting From $3.68
Overview
- Charges Single-Cell Li-Ion Battery from Wall Adapter and USB Inputs
- Automatic Input Power Detection and Selection
- Charge Current Programmable Up to 950mA from Wall Adapter Input
- Adjustable Output, High Efficiency 600mA Synchronous DC/DC Converter
- No External MOSFET, Sense Resistor or Blocking Diode Needed
- Thermal Regulation Maximizes Charge Rate Without Risk of Overheating*
- Preset Charge Voltage with ±0.6% Accuracy
- Programmable Charge Current Termination
- 1.5MHz Constant Frequency Operation (Step-Down Converter)
- 18μA USB Suspend Current in Shutdown
- “Power Present” Status Output
- Charge Status Output
- Automatic Recharge
- Available in a Thermally Enhanced, Low Profile (0.75mm) 16-Lead (5mm × 3mm) DFN Package
The LTC3550 is a standalone linear charger with a 600mA monolithic synchronous buck converter. It is capable of charging a single-cell Li-Ion battery from both wall adapter and USB inputs. The charger automatically selects the appropriate power source for charging.
Internal thermal feedback regulates the battery charge current to maintain a constant die temperature during high power operation or high ambient temperature conditions. The float voltage is fixed at 4.2V and the charge currents are programmed with external resistors. The LTC3550 terminates the charge cycle when the charge current drops below the programmed termination threshold after the final float voltage is reached. With power applied to both inputs, the LTC3550 can be put into shutdown mode reducing the DCIN supply current to 20μA, the USBIN supply current to 10μA, and the battery drain current to less than 2μA.
The DC/DC converter switching frequency is internally set at 1.5MHz, allowing the use of small surface mount inductors and capacitors.
| VOUT | |
| LTC3550 | Adjustable |
| LTC3550-1 | 1.875V |
Applications
- Cellular Telephones
Documentation
Data Sheet 1
User Guide 1
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. View our quality and reliability program and certifications for more information.
| Part Model | Pin/Package Drawing | Documentation | CAD Symbols, Footprints, and 3D Models |
|---|---|---|---|
| LTC3550EDHC#PBF | 16-Lead DFN (5mm x 3mm w/ EP) | ||
| LTC3550EDHC#TRPBF | 16-Lead DFN (5mm x 3mm w/ EP) |
| Part Models | Product Lifecycle | PCN |
|---|---|---|
|
Jul 29, 2026 - 26_0046 Discontinuation of Parts Manufactured in TSMC Fab 2 and 5 in Hsinchu, Taiwan. |
||
| LTC3550EDHC#PBF | ||
| LTC3550EDHC#TRPBF | ||
This is the most up-to-date revision of the Data Sheet.
Software Resources
Can't find the software or driver you need?
Request a Driver/SoftwareHardware Ecosystem
| Parts | Product Life Cycle | Description |
|---|---|---|
| Battery Monitors & Fuel Gauges 1 | ||
| LTC2942 | Obsolete | Battery Gas Gauge with Temperature, Voltage Measurement |
Tools & Simulations
LTspice
Models for the following parts are available in LTspice:
- LTC3550
- LTC3550-1
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.
Evaluation Kits
LTC3550EDHC | Dual Input USB/AC Adaptor Battery Charger and 600mA Synchronous Step-Down Converter