46
submitted 1 year ago* (last edited 1 year ago) by Machinist@lemmy.world to c/askelectronics@discuss.tchncs.de

Circuit is for controlling the fan on a Raspberry Pi, just on/off according to temp, no PWM. Not sure about the diode as it has a .7V drop and it's a tiny brushless DC motor. No markings on the fan so I measured the current with a multimeter when hooking it up to a USB charger. Circuit was adapted from here using what I have on hand.

Suggestions? Any advice is greatly appreciated!

*EDIT: Confirmed, this circuit works on a Raspberry Pi 4. Base was wired to GPIO 17 and manually tested using commands:

raspi-gpio set 17 op dh

raspi-gpio set 17 op dl

I didn't use a breadboard, just hack-n-slash with the wires coming out of the fan, the leads on the thru hole components, a jumper connected to gpio 17 as a socket for the base/resistor lead, and heat shrink tubing for insulation. Folded it up as I closed the housing. Case combo including heatsinks and fan here.

you are viewing a single comment's thread
view the rest of the comments
[-] Ghoti@lemmy.fmhy.ml 3 points 1 year ago

The diode is a fly back diode, it’s just circuit protection no need to worry about it.

[-] Machinist@lemmy.world 2 points 1 year ago

Yah. I added it as the original didn't have one. Think I should keep it?

[-] NextNoobi@discuss.tchncs.de 2 points 1 year ago* (last edited 1 year ago)

Well, It does no harm to the rest. So I would keep it.

load more comments (2 replies)
load more comments (2 replies)
this post was submitted on 11 Jul 2023
46 points (100.0% liked)

Ask Electronics

3173 readers
1 users here now

For questions about component-level electronic circuits, tools and equipment.

Rules

1: Be nice.

2: Be on-topic (eg: Electronic, not electrical).

3: No commercial stuff, buying, selling or valuations.

4: Be safe.


founded 1 year ago
MODERATORS