Digital 8 - Nothing particularly special about this GPIO pin.
Digital 6 - this pin can also be used as a PWM output pin using analogWrite().
Digital 5 - this pin can also be used as a PWM output pin using analogWrite().
Digital 4 - Nothing particularly special about this GPIO pin.
This pin can also be used as a PWM output pin using analogWrite()
Digital 3 - Also known as external interrupt #1.
This is used when programming with an FTDI cable but is available when using the native USB to program
#Adafruit trinket 5v power draw serial#
TX - also known as Digital #1, this is the hardware serial output pin.
RX - also known as Digital #0, this is the hardware serial input pin.
Make sure that you keep BAT+ low to minimize heat-loss! About 1 or 2 Volts higher than 3V or 5V is ideal. The regulator can supply approximately 150mA as long as it doesnt overheat. There is a 0.2V dropout due to the diode and maybe 50-100mV minimum drop in the regulator. The regulator is powered by either BUS or BAT (whichever is higher!) It will automatically switch between the two if USB or battery is removed using two schottky diodes. It is the output of the low dropout regulator.
#Adafruit trinket 5v power draw pro#
The next pin is either 3V or 5V depending on which Trinket Pro you have.
Don't put power into this pin, that's what BAT+ is for - use it only as an output! If you want to use the USB 5V power for something, like charging a battery, or if you need more than 150mA of current (this pin can supply 500mA+ from USB ports) or to detect when the Pro Trinket is plugged into USB, this pin will have 5V power on it if and only if its plugged into something via the micro B connector. This is the pin you'll want to use for any and all ground connections It is connected to the USB ground and the power regulator, etc.
GND is the common ground pin, used for logic and power.
This input is reverse-polarity protected. If you have a 5V Pro Trinket, 5.5V or higher is suggested. If you have a 3V Pro Trinket, you'll want at least 3.5V input to get a good 3.3V output. If you want to power the Pro Trinket from a battery or power adapter or solar panel or any other kind of power source, connect the + (positive) pin here! You can connect up to 16V DC.
We'll start with the top pins BAT+, GND, USB+, and 3V or 5V