FET circuit using a micro to a BJT to a FET? what circuit?

[ringo888]

FET circuit

Hi,

I have a project where I need to cycle the power on a 2.5” 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’t 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

 

[erikl]

FET circuit

Use a logic MOSFET switch or a semiconductor relay (photocoupler input).