Sequent Microsystems has launched a crowdfunding campaign for what it describes as the "ideal cooling solution" for the Raspberry Pi family of single-board computers, in particular the power-hungry Raspberry Pi 4 Model B.
"The Smart Fan is the most elegant, compact and inexpensive cooling solution for your Raspberry Pi," claims Sequent Microsystems' Mihai Beffa of the design. "It passes through all the GPIO pins allowing any number of add-on cards to be stacked on top of Raspberry Pi."
"The Smart Fan has the form factor of the Raspberry Pi HAT. Its own tiny 32-bit processor receives commands from Raspberry Pi through the I2C interface. A step-up power supply converts the 5 Volts provided by Raspberry Pi to 12 Volts, ensuring precise speed control. Using pulse width modulation, it powers the fan just enough to maintain a constant temperature of the Raspberry Pi processor."
The result is a device which draws less than 100 milliamps and keeps the fan speed as low as it can while still preventing the Raspberry Pi from hitting its thermal throttle point - something which, for heavy workloads, can dramatically impact the performance of the latest Raspberry Pi 4 Model B.
Like Sequent Microsystems' other add-on boards, the Smart Fan is designed to be stackable: While it's primary purpose is to sit at the bottom of a stack, below any other HAT add-ons, to cool the Raspberry Pi, additional Smart Fans can be added anywhere else in the stack for additional cooling - and the fan can be flipped between suck and blow.
Sequent Microsystems is taking orders for the Smart Fan on Kickstarter now, at $20 per fan or $30 with an optional DIN rail mounting kit. Shipments are expected to begin in March this year.