1. Home
  2. Hobby Electronics Basics
  3. FET circuitry

FET circuitry

Hi,

I have a project where I need to cycle the power on a 2.5=94 HDD, The power cycle is controlled by a micro. The drive need to be on during startup and switched off when the port pin on the micro is high. The micro does some initialization during startup for 5 secs (erasing SRAM, loading data) so it can=92t just switch the drive ON straight away. I was thinking of using a micro to a BJT to a FET but am not sure of the circuitry needed, again it needs to be on straight away and then switches off when the micro pin goes high, any idea guys?

Any help would be greatly appreciated.

Dave

Reply to
Dave_colq
Loading thread data ...

--
Assuming the port is an output, is active, and is low during power-up:
(View in Courier)


+V>-------------------+
                      |
                      S
µC PIN>-------------G PCH
                      D
                      |
                    [HDD]
                      |  
GND>------------------+

JF
Reply to
John Fields

Since most MCU ports are hi-Z on powerup, a pull-down resistor might be needed too.

Reply to
DJ Delorie 

--
Sure wouldn\'t hurt! :-)

JF
Reply to
John Fields

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.