Turning off connected ArduCAM

[Oitzu]

I have this nice spi camera ArduCAM Mini connected to a 3.3V arduino pro mini.

I would like to turn it off while the camera is not needed to save energy. (The low-power mode is not enough, it still drains about 40mA in low-power.)

Normally i would connect a n-channel mosfet (like the 2N7000) to the low-side of the Camera module.
The problem is: The module is, despite the mosfet "turned off", still draining about 20mA over the datalines to the arduino.

Does any one know a nice solution to switch the camera off on the "high side"?
(Probably a combination of an n and p-channel mosfet will do it?)

PS: The camera module also runs on 3.3V.

[5546dug]

@Oitzu
While I can't
Help you this
Is
A
Way
Cool project!

Is it running well and how do you get the pictures from the cam to the ? My sensors/ computer?

[Anticimex]

If you look in one of my schematics, I use a "high side" power toggle (see the "Optional MYSX 3.3V power toggle" box). You could probably use that type of design to toggle the power to the camera module. I use a single P-MOS (datasheet) with a pullup on the gate to keep the transistor closed by default, and enable it by pulling the gate low from the MCU. The transistor is especially designed for a low Rds(on) so it should be enough with only one.

[Oitzu]

@5546dug see http://forum.mysensors.org/topic/1668/sending-image-data-over-the-mysensors-network/9
I'm using a serial gateway connected to an raspberry pi with a perl script as "custom controller".
Running well atm but is still a little bit slow.

@Anticimex said:

If you look in one of my [schematics]...

Ah. Thanks, this looks exactly like what i need. Do you happen to know a similiar P-MOS in a through-hole technology package? (like to 220/92)

[Anticimex]

@Oitzu sorry no, I never considered those packages.

[Oitzu]

@Anticimex because i don't know any better...
Would this also work?

[Anticimex]

@Oitzu it should work just fine.

[Oitzu]

@Anticimex said:

@Oitzu it should work just fine.

Thanks. Ordered this. :+1: