LTC4009IUF-2#PBF

Battery Chargers Overview

The LTC4009IUF-2#PBF is a high-efficiency, multi-chemistry battery charger controller from Analog Devices. It utilizes a synchronous quasi-constant frequency PWM control architecture to prevent audible noise with ceramic capacitors. The device supports lithium-ion and lithium-polymer batteries, featuring pin-programmable output voltage for 4.2V/cell applications (LTC4009-2 variant). Key electrical parameters include an operating supply voltage range of 6 V to 28 V, an output current capability of 85 mA, and an adjustable output voltage range of 2 V to 28 V. It is housed in a QFN-20 package.

Battery Chargers Feature Summary

• Synchronous quasi-constant frequency PWM control architecture eliminates audible noise when using ceramic bulk capacitors.
• Pin-programmable output voltage configuration specifically designed for 4.2V/cell lithium-ion/polymer battery packs.
• Fully adjustable output voltage allows compatibility with a wide range of battery chemistries under external control.
• Integrated AC adapter input current limiting maximizes charge rate while maintaining fixed input power levels.

Battery Chargers Applications

• General-purpose battery charger controllers
• Lithium-ion battery pack charging systems
• Lithium-polymer battery management circuits
• Portable electronic devices requiring silent operation

Battery Chargers Procurement Notes

Verify the specific suffix '#PBF' indicates lead-free tape-and-reel or tube packaging as per manufacturer standards. Confirm the 'I' grade designation matches your required industrial temperature range specifications. Ensure the '-2' suffix aligns with your target cell voltage configuration needs. Cross-reference the Mouser part number 584-LTC4009IUF-2#PBF for current availability status. Check for any recent product change notices affecting pinout or electrical characteristics.

Battery Chargers Selection Notes

Select this component when silent operation with ceramic capacitors is critical. Choose the '-2' variant for standard 4.2V/cell lithium chemistry requirements. Consider the 85 mA output current limit for smaller capacity battery packs. Evaluate the need for external sense resistors for precise current programming. Verify that the 6 V to 28 V input range covers your system's power source variations.

Battery Chargers Part Context

This part belongs to the LTC4009 family of high-efficiency battery charger controllers. It shares the core synchronous buck PWM topology with variants like the LTC4009CUF-1#TRPBF but differs in temperature grade and packaging. The '-2' suffix distinguishes it from the '-1' version by setting the float voltage to 4.2V/cell instead of 4.1V/cell. It serves as a flexible solution for multi-chemistry applications compared to fixed-voltage chargers.

Battery Chargers Replacement Considerations

The LTC4009CUF-2#PBF is a commercial grade alternative with identical electrical functions but potentially different temperature ratings. The LTC4009CUF-1#TRPBF offers the same package but with a 4.1V/cell configuration. Verify thermal performance and temperature ranges when substituting between commercial and industrial grades.

Battery Chargers FAQ

Does the LTC4009 generate audible noise with ceramic capacitors?

No, the device uses a synchronous quasi-constant frequency PWM control architecture that prevents audible noise even with ceramic bulk capacitors.

What is the difference between the LTC4009-1 and LTC4009-2 versions?

The LTC4009-1 provides an output voltage of 4.1V/cell, while the LTC4009-2 (such as the IUF-2) is configured for 4.2V/cell lithium-ion/polymer battery packs.

How is the AC adapter input current limited?

An external sense resistor programs the input current limit, and the ICL status pin indicates when the charge current is reduced due to AC adapter current limiting.