Need to control 5v output with 3v propeller pin

wdfreemanjr

Hello,

I am trying to control a small pager motor. I don't need direction or speed control (just on/off). I am making a pin an output and then setting it to high. This gives me 3.3 volts which works fine, but I really need 5 volts which is available on my PPDB. Do I need to use a PNP transistor or something and if so, which one. Any suggestions or a better solution would be greatly appreciated. Simple circuit design would be great if possible.

Thanks

Great product. With only a few hours of time I was able to:

Control an LED
Read a photoresister by measuring capacitor discharge time
Write to the debug window using Serial Terminal
Control a server motor both position and continuous
Read from the ColorPal module

Mike Green

See Nuts and Volts Column #6 (here). It's written for the Stamps, but the same technique applies to the Propeller. The last page shows how the protective diode is connected. You need one of these too. A 1N4001 or 1N914 or similar diode will work.

You may want to use a smaller resistor value than the 390 Ohms shown because the Prop puts out 3.3V rather than the 5V of the Stamps. 220 Ohms would provide 15mA base current, more than enough for pretty much any transistor.

JonnyMac

You don't want to connect a Propeller pin to any kind of inductive device. Here's a simple circuit that will let you control the motor safely. If you do need speed control, the Propeller counters and a simple bit of code will take care of that (I just finished a dual motor control project for a friend).

wdfreemanjr

Thanks guys,

That is just what I needed... Good advice and good circuit. I only need to figure out how to mark this thread as solved.

Bill

Sapieha

Hi wdfreemanjr.

For possibility to change status You need open Yours first post as EDIT.

wdfreemanjr wrote: »

Thanks guys,

That is just what I needed... Good advice and good circuit. I only need to figure out how to mark this thread as solved.

Bill

doggiedoc

Bill, click on "Edit Post" in your original post, then select "Go Advanced" and at the top of the window you can change the prefix option to "solved".