powering on parts of your circuit using mosfets?

Go To Last Post
7 posts / 0 new
Author
Message
#1
  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

Hello helpful guys :)

I am thinking of powering on a 5V device that connects to me 3.3V micro. The micro talks to the device using usb (so device supply is 5V).

I have a 12V to 5.0V SMPS chip that supplies the usb device and from that 5V I am going to use 3.3V regulator chip to drive my UC3 micro controller. I want to be able to power cycle the 5V supply to the USB device so I am thinking of a mosfet like facility...

It would be good to be able to place the switch on the high side that way the USB device ground is at the same ground as the microcontroller.

Any suggestions?

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

I want to avoid using a transistor solution. The current required for the USB device can be up to 500mA.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

You can use either a P-FET, or a high side switch driver that uses an N-FET.

Writing code is like having sex.... make one little mistake, and you're supporting it for life.

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

...or a small regulator with a On/Off pin....

John Samperi

Ampertronics Pty. Ltd.

www.ampertronics.com.au

* Electronic Design * Custom Products * Contract Assembly

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

hhhm... found a few load switches ADP197 being a good one with low rds! but the package option makes it a bad choice for me!

Look like element14 stocks a few of the STMPSxxxx units...

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

In the past I said ...
https://www.avrfreaks.net/index.p...

Ross McKenzie ValuSoft Melbourne Australia

  • 1
  • 2
  • 3
  • 4
  • 5
Total votes: 0

MIC2005...I think I am going to choose!