What it is:

PowerWing is a FeatherWing that is able to power a Feather platform anywhere 6-36V is available. The onboard TI LMZ4201H integrated buck converter is able to efficiently convert the input voltage into 5V at up to 1A of current output. This means there is enough power to supply a wide array of multiple Feather devices simultaneously.

Features:

• 6-36V input voltage
• 5V at up to 1A output
• Efficiency over 90% (up to 24V in and 1A output)
• Reverse polarity protection in case of accidental reverse connection
• Protection against transient overvoltage from noisy power sources
• Uses 0805 components to easily be able to customize the design for your own application
• Separate enable wire to turn on and off your Feather project externally from 8-36V source (by default PowerWing turns on and off with input supply voltage, a simple solder jumper makes enable wire functional)
• Ability to measure supply voltage from Feather ADC

Setup Notes:

The input connector accepts 20-26 AWG wire. The leads should be tinned with solder before inserting into connector. Wire can be removed by inserting a small screwdriver into back of connector, and pulling on the wire.

The Feather platform was designed to be used with either a USB supply, or from a lithium ion battery pack. The PowerWing board repurposes the battery supply pin (J1). This means you cannot hook up a lithium ion battery to the Feather without causing damage! When you plug a Feather to a USB port it will disable the VBAT supply to the Feather board and power from the USB source. When you disconnect, it will automatically switch to the PowerWing supply.

As supplied the external enable wire is not functional. The PowerWing board will turn on immediately when input voltage is supplied. To use the external enable wire (pin 3 of J2), short pins 1-2 of SJ1 with solder. If you short pins 2-3 of SJ1, the enable pin will connect to the EN pin of the Feather. This means the PowerWing will supply 5V whenever input voltage is supplied, but the Feather will powered down until the enable is activated. This can be used to have an always on functionality for some 5V devices, while only having the main Feather powered up when needed.

The input voltage to the PowerWing can be monitored from the Feather ADC pins using pin 5 of P2. Select the pin with a solder jumper on the backside of the board. The input voltage is divided by 12 using R2 and R3. This means 0-36V on the input is scaled to 0-3.3V for the ADC.

Plated through holes are provided to solder external wires for output voltage, ground, and enable functions.