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Full machine-readable index: https://core-electronics.com.au/llms.txt # SparkFun MOSFET Power Switch and Buck Regulator (Low-Side) **Type:** Product page · **SKU:** COM-23979 · **Brand:** [Sparkfun](https://core-electronics.com.au/brands/sparkfun-australia) **Page:** https://core-electronics.com.au/sparkfun-mosfet-power-switch-and-buck-regulator-low-side.html ([markdown](https://core-electronics.com.au/sparkfun-mosfet-power-switch-and-buck-regulator-low-side.html.md)) The MOSFET Power Switch and Buck Regulator (Low-Side) can be powered with up to 12V and control up to 10A, all while providing a sweet 3.3V... ## Pricing - **Price:** $27.55 (inc GST) — $25.05 AUD, exc GST - **Quantity discounts:** 5+ $24.29 (exc GST) · 25+ $23.79 (exc GST) · 100+ $22.79 (exc GST) ## Availability & dispatch - Available with a lead time — expect dispatch between Aug 24 and Aug 25. ## How to buy - **Build a cart:** compose `https://core-electronics.com.au/cart/link?items=COM-23979:1` (comma-separated SKU:qty pairs) and share the link. 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Share the cart link; checkout takes it from there. - **Search the catalogue:** `https://core-electronics.com.au/search/{query}.md` (URL-encode the query; pages 2-3 at `search/{query}/{page}.md`; `search.md?q=` also works) - **Payment methods, purchase orders, policies and contact details:** https://core-electronics.com.au/llms.txt ## Description Does your microcontroller need to control a high-voltage item, like a 12V LED strip, while also needing to be powered? Do you want to avoid having multiple power adapters and microcontrollers for your project? The MOSFET Power Switch and Buck Regulator (Low-Side) is one product Sparkfun needed at SparkFun, so Sparkfun figured other folks might have the same problem. Power the board with up to 12V and control up to 10A, all while providing a sweet 3.3V to your control board. The SparkFun MOSFET Power Switch and Buck Regulator (Low-Side) combines two circuits into one board: an LMR14203 buck regulator configured to output 3.3V and an N-channel MOSFET (PSMN7R0-100BS) configured as a low-side switch. A flyback diode is also on the load side for devices with back EMF! Simply pull the CTL pin low to activate the load. Various connectors (barrel jack, female header, and poke-home) are provided to connect a power supply to a microcontroller of your choice (Arduino, micro-bit, Raspberry Pi’s microcontroller) and load them together. VCC, 3.3V, CTL, and GND are also broken out through 0.1" spaced PTHs for those who prefer to solder. Two LEDs (PWR\_LED and ON\_LED) indicate when there is 3.3V and whenever power is applied to the load. Jumpers are included on the back to disable the LEDs. A MEAS PTH jumper is also included for those interested in precisely measuring the current consumption of the system. **Note:** While the MOSFET is rated to 100A/100V, Sparkfun don't recommend you go much above 10A as the PCB polygon pours and traces become the limiter. [Get Started With the SparkFun MOSFET Power Switch and Buck Regulator Guide](https://docs.sparkfun.com/SparkFun_MOSFET_Power_Switch_and_Buck_Regulator_Low-Side)### Features - Input Voltage Range: 4.5V to 12V - LMR14203 Step Down Voltage Regulator - Configured to Output 3.3V/300mA - PSMN7R0-1000BS N-Channel MOSFET - Configured as a Low-Side Switch - Connectors - Input: 5.5mm x 2.1mm Barrel Jack (Center-Positive) - Output: Poke-Home Connectors - Control: 1x4 Female Headers - 0.1"-spaced PTHs - Built-in Flyback Diode on Load - LEDs - PWR - ON - Jumpers - PWR\_LED - MEAS - ON\_LED - Dimensions: 1.50" x 1.50" (38.1mm x 38.1mm) - Weight: 9.9g ### Documents - [Schematic](https://core-electronics.com.au/attachments/localcontent/SparkFun_MOSFET_Power_Switch_and_Buck_Regulator_Low-Side_Schematic_V11_1416841ef78.pdf) - [Eagle Files](https://core-electronics.com.au/attachments/localcontent/SparkFun_MOSFET_Power_Switch_and_Buck_Regulator_Low-Side_V11_214365f29ea.zip) - [Board Dimensions](https://core-electronics.com.au/attachments/localcontent/SparkFun_MOSFET_Power_Switch_and_Buck_Regulator_Low-Side_Board_Dimensions_61004ff43ac.png) - [Hookup Guide](https://docs.sparkfun.com/SparkFun_MOSFET_Power_Switch_and_Buck_Regulator_Low-Side) - [Fritzing Part](https://github.com/sparkfun/Fritzing_Parts/blob/main/products/23979_sfe_n-channel_mosfet_power_switch_buck_regulator_low-side_transistor.fzpz) - Datasheet - [LMR14203](https://core-electronics.com.au/attachments/localcontent/lmr14203_517122f390d.pdf) - [PSMN7R0-100BS](https://core-electronics.com.au/attachments/localcontent/PSMN7R0-100BS_99432a30572.pdf) - [GitHub Hardware Repo](https://github.com/sparkfun/SparkFun_MOSFET_Power_Switch_and_Buck_Regulator_Low-Side) ## Images - [Product image 1](https://core-electronics.com.au/media/catalog/product/C/O/COM-23979-1.jpg)