TCA9535MRGER

TCA9535MRGER is Texas Instruments’ 16‑bit I2C I/O expander. It lets you add 16 programmable digital I/O pins to a microcontroller over a standard I2C bus, freeing MCU GPIOs. It provides two 8‑bit ports (PORT0/PORT1) with independently configurable directions and outputs, plus input readback and a polarity inversion option. Core registers include: Configuration Register (1 = output, 0 = input), Input Port Registers, Output Port Registers, and Polarity Inversion Register. An interrupt output (INT) can alert a host to input changes. The device supports a 1.65–5.5 V supply, I2C speeds up to 400 kHz (Standard/Fast mode), and up to 8 devices on the same bus using address pins A0–A2. The MRGER suffix designates a specific package variant; check the TI datasheet for exact pinout. Typical uses include LED driving, sensor interfacing, and expanding I/O for microcontrollers with limited GPIO. For detailed specs and pinouts, refer to the TCA9535MRGER datasheet.

Equivalent I2C 16‑bit I/O expanders to TI TCA9535MRGER:
- NXP PCA9535
- NXP PCA9555
- NXP PCF8575 / PCF8575A
- Microchip MCP23017
Note: check each device’s address pins, voltage range, and package to ensure interchangeability.

Here are the main features of TCA9535MRGER (I/O expander):
- 16-bit I/O expander for I2C-bus (two 8-bit ports: PORT0 and PORT1)
- Per-pin direction control (IODIR) for inputs or outputs
- GPIO data read/write with output latch (OLAT) for deterministic writes
- Polarity inversion per pin (IPOL)
- Per-pin pull-up enable (GPPU)
- Interrupt output with configurable interrupt on change (GPINTEN/INTCON/DEFVAL)
- 3-bit hardware address selection (A0–A2), up to 8 devices on bus
- I2C interface: supports standard and fast-mode (up to 400 kHz)
- Supply voltage range: 1.65 V to 5.5 V
- Operating temperature: typically -40°C to 85°C
- Packaging: 28-pin VSSOP (MRGER)
These make it suitable for expanding GPIOs on I2C-equipped systems with flexible I/O configuration and simple interrupt handling.

- Pin count: 28 pins (MRGER package)
- Function: 16‑bit I2C I/O expander with two 8‑bit GPIO ports (Port0/Port1) for expanding MCU I/O via I2C (with address pins and interrupt capability).

- Manufacturer: NXP Semiconductors.
- Company type: Dutch multinational semiconductor company that designs and manufactures chips for automotive, industrial, communications, and consumer electronics markets (headquartered in Eindhoven, Netherlands).

Typical applications of the TCA9535MRGER (16‑bit I/O expander via I2C) include:
- Extending MCU/SoC GPIOs in embedded systems and SBCs (Arduino, Raspberry Pi)
- Driving indicators/LEDs and simple displays
- Keyboard, keypad, and switch input scanning
- Reading multiple sensors and general-purpose inputs
- Interfaces for LED matrices and small I/O interfacing in automation
- Industrial, building, and home automation devices
- Portable/consumer electronics requiring extra GPIOs

The TCA9535MRGER is in a 24-pin TSSOP (lead-free, RoHS, Green) package, available in Tape & Reel.