FTM Board Club
Fairchild Semiconductor
5V Output, Low Power Boost Regulator

The FAN4860 Evaluation Board is a compact circuit including Fairchild’s FAN4860UMP 5V output, lowpower boost regulator in a 6-lead 2x2mm Ultra-Thin MLP Package.

Small input/output capacitors and a 1uH inductor ensure smooth output regulation. The board also features an on-board active load circuit and footprints to accommodate additional input/output capacitors. The FAN4860 Evaluation Board provides probe access points to all key circuit nodes so that electrical characteristics can be measured with ease.

The FAN4860 is a low-power boost regulator designed to provide a regulated 5V output from a single cell Li-Ion battery. The output voltage is fixed at 5.0V with a guaranteed maximum load current of 200mA at VIN=2.3V and 300mA at VIN=3.3V. Input current in shut-down mode is less than 1΅A, which maximizes battery life. Light-load PFM operation is automatic and “glitch-free”. The regulator maintains output regulation at no-load with 37΅A quiescent current. The combination of built-in power transistors, synchronous rectification, and low supply current make the FAN4860 ideal for battery powered applications.


• Operates with Very Small External Components: 1΅H Inductor and 0402 Case Size Input and Output Capacitors
• Input Voltage Range from 2.3V to 4.5V
• Fixed 5.0V Output Voltage
• Maximum Load Current 200mA at VIN=2.3V
• Maximum Load Current 300mA at VIN=3.3V
• Up to 92% Efficient
• Low Operating Quiescent Current
• True Load Disconnect During Shutdown
• Variable On-Time Pulse Frequency Modulation (PFM) with Light-Load Power-Saving Mode
• Internal Synchronous Rectifier (No External Diode Needed)
• Thermal Shutdown and Overload Protection
• 6-Pin 2 x 2mm UMLP
• 6-Bump WLCSP, 0.4mm Pitch