Features and Benefits
- Standalone USB Charger
- Up to 950mA Charge Current Programmable via Single Resistor
- HPWR Input Selects 20% or 100% of Programmed Charge Current
- NTC Input for Temperature Qualified Charging
- Internal Timer Termination
- Bad Battery Detection
- CHRG indicates C/10 or Timeout
- 400mA Output Current
- 2.25MHz Constant Frequency Operation
- Zero Current in Shutdown
- Low Noise Pulse Skip Operation or Power Saving Burst Mode Operation
- Low No Load Quiescent Current: 35μA
- Available in a Low Profile Thermally Enhanced 16-Lead 3mm × 3mm QFN Package
The LTC3559/LTC3559-1 are USB battery chargers with dual high efficiency buck regulators. The parts are ideally suited to power single-cell Li-Ion/Polymer based handheld applications needing multiple supply rails.
Battery charge current is programmed via the PROG pin and the HPWR pin, with capability up to 950mA at the BAT pin. The battery charger has an NTC input for temperature qualified charging. The CHRG pin allows battery status to be monitored continuously during the charging process. An internal timer controls charger termination.
Each monolithic synchronous buck regulator provides up to 400mA of output current while operating at efficiencies greater than 90% over the entire Li-Ion/Polymer range. A MODE pin provides the flexibility to place both buck regulators in a power saving Burst Mode operation or a low noise pulse skip mode.
The LTC3559/LTC3559-1 are offered in a low profile thermally enhanced 16-lead (3mm × 3mm) QFN package.
- SD/Flash-Based MP3 Players
- Low Power Handheld Applications
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 1085 is a Linear USB Battery Charger with Dual Buck Regulators featuring the LTC3559. The LTC3559 is a CC/CV 5V/USB linear battery charger with dual high efficiency buck regulators. The part is ideally suited to power single cell 4.2V Li-Ion/Polymer-based handheld applications needing multiple supply rails. The DC1085 has a 4.35V to 5.5V input voltage range and is configured to provide up to 500mA of charge current, though the part is capable of providing up to 950mA. The battery charger has an NTC input for temperature qualified charging. Each monolithic synchronous buck regulator provides up to 400mA of output current while operating at efficiencies greater than 90% over the entire Li-Ion/Polymer range. The buck output voltages are set at 2.5V and 1.2V.
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.