8-Channel PWM/Servo FeatherWing Add-on info
8-Channel PWM/Servo Feather Wing Add-on allows generating 8 x 12-bit PWM outputs with Feather boards. Using Feather Stacking Headers or Feather Female Headers you can connect a FeatherWing on top or bottom of your Feather board.
PWM/Servo Feather Wing can be used for making robots which have many joints like a hexapod walker. Another application for this cool board is precise control of LEDs. Similar to other Adafruit PWM/Servo boards, you don’t have to send constant PWM signals to control the board. Just a single signal over I2C is enough to generate a PWM signal.
PWM/Servo Feather Wing only uses I2C pins, so it can be used with any Feather boards (ATmega32u4, ATSAM M0 or ESP8266 based). It can also be stacked with other Feather wings, providing it has a distinct address.
The PWM chip used in this Feather wing has the following specs:
- Includes an I2C-controlled PWM driver with a built in clock. That means that you do not need to continuously send it signal tying up your microcontroller.
- 5V compliant, which means you can control it from a 3.3V Feather and still safely drive up to 6V outputs (this is good for when you want to control white or blue LEDs with 3.4+ forward voltages)
- 6 address select pins so you can stack up to 62 of these on a single i2c bus, a total of 992 outputs.
- Adjustable frequency PWM up to about 1.6 KHz
- 12-bit resolution for each output - for servos, that means about 4us resolution at 60Hz update rate
- Configurable push-pull or open-drain output
Adafruit also added some extras to the wing besides the chip.
- Reverse polarity protected terminal blocks for power input (or you can use the 0.1" breakouts on the side)
- Green power-good LED
- Two groups of 4 outputs on either side, 8 total.
- A spot to place a big capacitor on the V+ line (in case you need it)
- 220 ohm series resistors on all the output lines to protect them, and to make driving LEDs trivial
This product comes with a fully tested and assembled wing as well as 2 pieces of 3x4 male straight header (for servo/LED plugs), a 2-pin terminal block (for power) and a stick of 0.1" header so you can plug into a Feather. A little light soldering will be required to assemble and customize the board by attaching the desired headers but it is a 15 minute task that even a beginner can do.
8-Channel PWM/Servo Feather Wing Add-On - General Specifications
- Includes an I2C-controlled PWM driver with a built in clock. That means that you do not need to continuously send it signal tying up your microcontroller.
- 5V compliant, which means you can control it from a 3.3V Feather and still safely drive up to 6V outputs (this is good for when you want to control white or blue LEDs with 3.4+ forward voltages)
- 6 address select pins so you can stack up to 62 of these on a single i2c bus, a total of 992 outputs - that's a lot of servos or LEDs
- Adjustable frequency PWM up to about 1.6 KHz
- 12-bit resolution for each output - for servos, that means about 4us resolution at 60Hz update rate
- Configurable push-pull or open-drain output
- Terminal block for power input (or you can use the 0.1" breakouts on the side)
- Reverse polarity protection on the terminal block input
8-Channel PWM/Servo Feather Wing Add-On - Technical Specifications
- Dimensions: 50.8mm x 22.9mm x 1.6mm / 2" x 0.9" x 0.06"
- Weight: 3.9g
Documents
PCA9685 Datasheet
References
Adafruit Product Page: https://www.adafruit.com/products/2928
