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MAX31856 Breakout 3263 Voltage requirements
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MAX31856 Breakout 3263 Voltage requirements

by DonMcDonald on Wed Jun 12, 2019 12:11 pm

The MAX31856 Breakout 3263 is listed as having a 3.3 to 5V power supply. The data sheet for the voltage regulator on board (MIC5225-3.3) shows a Max dropout voltage of 450mV. If I am reading that correctly any input voltage below 3.75V may causes issues with holding an output voltage of 3.3V. How\why is this board listed with a 3.3 to 5V supply rather than a 3.75 to 5V supply?

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Re: MAX31856 Breakout 3263 Voltage requirements

by adafruit_support_bill on Wed Jun 12, 2019 1:03 pm

The data sheet for the voltage regulator on board (MIC5225-3.3) shows a Max dropout voltage of 450mV.

The spec you are quoting is the worst-case dropout voltage with a 150mA load.
The MAX31856 only draws about 1.2mA, so the actual dropout voltage will be much lower. But even with the worst-case figure you quote, the supply voltage will be well within the 3.0v-3.6v operating voltage rating of the MAX31856.

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Re: MAX31856 Breakout 3263 Voltage requirements

by cmefryday on Fri Aug 09, 2019 12:50 pm

My Grand Central Metro M4 will power the MAX31856 fine from the Metro's 5V pin, but the 3.3V pin causes the M4 to enter safe mode.

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