Skip to main content

PCAL6416A - Overview

PCAL6416A I/O Expander​

The PCAL6416A is a 16-bit I²C GPIO expander from NXP Semiconductors. It adds 16 programmable input/output pins to a microcontroller over two I²C wires, with built-in interrupt support, programmable pull-up/pull-down resistors, input latching, and voltage-level translation between different logic levels. The board is Qwiic compatible, so it plugs straight into any Qwiic-enabled microcontroller without soldering, or you can wire it up over standard I2C pins instead.

PCAL6416A I/O Expander
PCAL6416A I/O Expander

Which product is this documentation for?​

⚠️
The webstore link for this product is not available yet! We're working on it. In the meantime, please contact us for more information.

Key Features​

  • 16 GPIO Pins: Provides 16 programmable input/output pins divided into two 8-bit ports.
  • I²C Communication: Supports Standard-mode (100 kHz) and Fast-mode (400 kHz), default address 0x20.
  • 3.3V or 5V Operation: Runs the PCAL6416A at 3.3V by default through an onboard regulator, or at 5V instead if you bypass the regulator with a jumper.
  • Voltage-Level Translation: Allows communication between devices operating at different logic voltages.
  • Interrupt Output (INT): Open-drain interrupt pin notifies the microcontroller when an input changes state.
  • Configurable Pull-Up/Pull-Down Resistors: Can be enabled individually for each pin.
  • Low Power Consumption: Standby current as low as 0.5 µA typical (rising to 1.5 µA typical at higher supply voltages); enabling internal pull-ups on every pin raises this to about 1.1 mA typical.
  • LED Driving Capability: Each output pin can sink up to 25 mA, enough to drive LEDs directly.

You may also need​

Qwiic cable

Qwiic cable

Qwiic (formerly easyC) compatible cables with connectors on both ends, available in various lengths.