SparkFun
FemtoBuck LED Driver
The FemtoBuck is a compact, single-channel constant-current LED driver capable of driving high-power LEDs at up to 350 mA with input voltages up to 36 V. Dim...
The FemtoBuck is a compact, single-channel constant-current LED driver capable of driving high-power LEDs at up to 350 mA with input voltages up to 36 V. Dimming is controlled via PWM or an analog signal (0–2.5 V), and the driver achieves approximately 95% efficiency across its operating range.
Based on the AL8805 driver IC, the FemtoBuck features dual power input and dimming control pins, a footprint for a 3.5 mm screw terminal, and zip-tie anchor points for securing wires. A solder jumper on the board can be closed to double the output current from 330 mA to 660 mA.
Key Features
- Constant Current Output – 330 mA default, 660 mA with solder jumper
- Wide Input Voltage – Up to 36 V
- ~95% Efficiency – Minimal heat generation
- PWM or Analog Dimming – 0–2.5 V analog or PWM input
- Compact Design – Small footprint with screw terminal option
- Zip-Tie Anchors – Secure wires to the board after soldering
Specifications
- Driver IC – AL8805W5
- Output Current – 330 mA (660 mA with solder jumper)
- Input Voltage – Up to 36 V
- Dimming Control – PWM or 0–2.5 V analog
- Efficiency – ~95%
- Channels – 1
Resources
Jargon buster
Plain-language definitions for the technical terms used above.
- LED driver
- An LED driver is a control chip or circuit that supplies and switches power to LEDs. For a display board, it reduces the number of microcontroller pins needed and handles tasks like lighting the right segments and adjusting brightness.
- PWM
- Pulse Width Modulation is a way for a digital pin to simulate variable output power by switching on and off very quickly. It matters for controlling things like LED brightness, motor speed, or servo-style signals from a microcontroller pin.
- solder jumper
- A solder jumper is a small pair or group of pads on a circuit board that can be bridged or cut with solder to change a hardware setting. It matters because changing modes may require careful soldering rather than just changing software.
Find this product in
FemtoBuck LED Driver Schematic v1.3
Schematic · 70.6 KB · Click any page to view full size
AL8860 LED Driver IC Datasheet
Datasheet · 1000.7 KB · Click any page to view full size
FemtoBuck LED Driver Schematic v1.2
Schematic · 72.0 KB · Click any page to view full size
AL8805 LED Driver IC Datasheet
Datasheet · 960.1 KB · Click any page to view full size
Supplier page — sparkfun.com
Supplier Description · 687.8 KB · Click any page to view full size
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