Power external devices

Question

I need to power an external device which has two pins of 1.2v and two of 3.3v. Is it possible to power them with the PI?

Power Specifications

Source                      Min         Typ     Max         Comments
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3V3 voltage                 3.135 V     3.3 V   3.4651 V |  3.3V ±5%
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3V3 active supply current               850 mA  1100 mA  |  Design for 1.5 A peak
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3V3 supply ripple                               50 mV    |  Peak to peak
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1V2 voltage                 1.14 V      1.2 V   1.26 V   |  1.2 V ±5%
----------------------------------------------------------------------------------
1V2 active supply current               165 mA  200 mA   |  1V2 supply ripple
----------------------------------------------------------------------------------
                                                25 mV    |  Peak to peak
----------------------------------------------------------------------------------

score 1 · Answer 1 · answered Sep 17 '16 at 13:06

RPi has 5V and 3V3 power outputs exposed on the GPIO. Since your board needs to be ready for 1.5A max current on the 3V3 input, you cannot use the RPi 3V3 power output as it has a low current rating. You'll end up having to do some transforming: 5V to 3V3 (the RPi 5V supply can handly 1.5A provided you have a robust power supply rated 3A or more) and 3V3 to 1V2 (either from the 3V3 source you get from 5V, or separately from the RPi's 3V3 output). Then make sure you wire it up according to the described implementation.

Power external devices

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