SparkFun MOSFET Power Switch and 3.3V Buck Regulator (Low-Side)
Controls high-voltage items
Powers up to 12V, 10A loads
Stable 3.3V output
Versatile connection options
Onboard current measurement
The SparkFun MOSFET Power Switch and 3.3V Buck Regulator (Low-Side) is designed to facilitate the control of high-voltage items, such as a 12V LED strip, while simultaneously providing power. This device is capable of powering a board with up to 12V and controlling a current of up to 10A, delivering a stable 3.3V to the control board.
This product integrates an LMR14203 buck regulator, which is set to output 3.3V, and an N-channel MOSFET (PSMN7R0-100BS) that functions as a low-side switch. It includes a flyback diode on the load side to accommodate devices that generate back electromotive force. Activation of the load is achieved by pulling the CTL pin low.
The device offers a variety of connectors, including a barrel jack, female header, and poke-home connectors, allowing for versatile connections to a range of microcontrollers. Additionally, VCC, 3.3V, CTL, and GND are accessible via 0.1" spaced plated-through holes for soldering preferences. The board features two LEDs to indicate the presence of 3.3V and when power is applied to the load. For those who do not require the LEDs, jumpers on the back can be used to disable them. Furthermore, a MEAS PTH jumper is provided for precise current consumption measurements of the system.
Please note that while the MOSFET is capable of handling 100A/100V, it is advised not to exceed 10A due to the limitations of the PCB polygon pours and traces.
1x SparkFun MOSFET Power Switch and 3.3V Buck Regulator (Low-Side)
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