# 16 Channel I2C 24VDC Digital Input Module

16 channel digital input module based on MCP23017. Designed for reliable input monitoring in industrial and embedded applications.

- **Seller:** [EA Control Tech](https://lectronz.com/stores/eacontroltech), Oakland, California, United States
- **Price:** $40.00 (USD, before shipping and taxes)
- **Availability:** In stock
- **Categories:** Application, Equipment, Technology
- **Country of origin:** United States
- **Product page:** https://lectronz.com/products/-16-channel-i2c-24vdc-digital-input-module

## Links

- [Documentation](https://eacontroltech.com/16_DI_MCP23017.pdf)
- [Schematics](https://eacontroltech.com/16_DI_MCP23017_Schematic.pdf)

## Images

![16 Channel I2C 24VDC Digital Input Module](https://lectronz-images.b-cdn.net/lectronz/active_storage/representations/proxy/eyJfcmFpbHMiOnsiZGF0YSI6Njg4NzEsInB1ciI6ImJsb2JfaWQifX0=--f58a121a15ca33dc5ba5bde55eb3a113b0a2a741/eyJfcmFpbHMiOnsiZGF0YSI6eyJmb3JtYXQiOiJqcGVnIiwicmVzaXplX3RvX2xpbWl0IjpbOTYwLDY0MF0sInNhdmVyIjp7InN0cmlwIjp0cnVlfX0sInB1ciI6InZhcmlhdGlvbiJ9fQ==--4e27bac8cdfb621fb828f6a3a5982fe1a423b516/16_DI_MCP23017_1.jpeg)
![16 Channel I2C 24VDC Digital Input Module](https://lectronz-images.b-cdn.net/lectronz/active_storage/representations/proxy/eyJfcmFpbHMiOnsiZGF0YSI6Njg4NzUsInB1ciI6ImJsb2JfaWQifX0=--95e78e1a1a7fa6e1453d2cf77913157c69bf98d1/eyJfcmFpbHMiOnsiZGF0YSI6eyJmb3JtYXQiOiJqcGVnIiwicmVzaXplX3RvX2xpbWl0IjpbOTYwLDY0MF0sInNhdmVyIjp7InN0cmlwIjp0cnVlfX0sInB1ciI6InZhcmlhdGlvbiJ9fQ==--4e27bac8cdfb621fb828f6a3a5982fe1a423b516/16_DI_MCP23017_2.jpeg)
![16 Channel I2C 24VDC Digital Input Module](https://lectronz-images.b-cdn.net/lectronz/active_storage/representations/proxy/eyJfcmFpbHMiOnsiZGF0YSI6Njg4NzksInB1ciI6ImJsb2JfaWQifX0=--c7a9a52fc1fc6d7dac3f42734e4ff0cb20eaa5e3/eyJfcmFpbHMiOnsiZGF0YSI6eyJmb3JtYXQiOiJqcGVnIiwicmVzaXplX3RvX2xpbWl0IjpbOTYwLDY0MF0sInNhdmVyIjp7InN0cmlwIjp0cnVlfX0sInB1ciI6InZhcmlhdGlvbiJ9fQ==--4e27bac8cdfb621fb828f6a3a5982fe1a423b516/16_DI_MCP23017_3.jpeg)
![16 Channel I2C 24VDC Digital Input Module](https://lectronz-images.b-cdn.net/lectronz/active_storage/representations/proxy/eyJfcmFpbHMiOnsiZGF0YSI6Njg4ODMsInB1ciI6ImJsb2JfaWQifX0=--425d3cbfc0920fa812da76001e2ef08b46b08cad/eyJfcmFpbHMiOnsiZGF0YSI6eyJmb3JtYXQiOiJqcGVnIiwicmVzaXplX3RvX2xpbWl0IjpbOTYwLDY0MF0sInNhdmVyIjp7InN0cmlwIjp0cnVlfX0sInB1ciI6InZhcmlhdGlvbiJ9fQ==--4e27bac8cdfb621fb828f6a3a5982fe1a423b516/16_DI_MCP23017_4.jpeg)
![16 Channel I2C 24VDC Digital Input Module](https://lectronz-images.b-cdn.net/lectronz/active_storage/representations/proxy/eyJfcmFpbHMiOnsiZGF0YSI6Njg4ODcsInB1ciI6ImJsb2JfaWQifX0=--8913b56e3a247060e90a610a3caf5e81c45517cf/eyJfcmFpbHMiOnsiZGF0YSI6eyJmb3JtYXQiOiJqcGVnIiwicmVzaXplX3RvX2xpbWl0IjpbOTYwLDY0MF0sInNhdmVyIjp7InN0cmlwIjp0cnVlfX0sInB1ciI6InZhcmlhdGlvbiJ9fQ==--4e27bac8cdfb621fb828f6a3a5982fe1a423b516/16_DI_MCP23017_5.jpeg)
![16 Channel I2C 24VDC Digital Input Module](https://lectronz-images.b-cdn.net/lectronz/active_storage/representations/proxy/eyJfcmFpbHMiOnsiZGF0YSI6Njg4OTEsInB1ciI6ImJsb2JfaWQifX0=--e51f420ed60f5330ddd6ef08dceab77809df93b6/eyJfcmFpbHMiOnsiZGF0YSI6eyJmb3JtYXQiOiJqcGVnIiwicmVzaXplX3RvX2xpbWl0IjpbOTYwLDY0MF0sInNhdmVyIjp7InN0cmlwIjp0cnVlfX0sInB1ciI6InZhcmlhdGlvbiJ9fQ==--4e27bac8cdfb621fb828f6a3a5982fe1a423b516/16_DI_MCP23017_6.jpeg)
![16 Channel I2C 24VDC Digital Input Module](https://lectronz-images.b-cdn.net/lectronz/active_storage/representations/proxy/eyJfcmFpbHMiOnsiZGF0YSI6Njg4OTUsInB1ciI6ImJsb2JfaWQifX0=--84e6c6415c885340e6dda5d1b9ad5d0588845b10/eyJfcmFpbHMiOnsiZGF0YSI6eyJmb3JtYXQiOiJqcGVnIiwicmVzaXplX3RvX2xpbWl0IjpbOTYwLDY0MF0sInNhdmVyIjp7InN0cmlwIjp0cnVlfX0sInB1ciI6InZhcmlhdGlvbiJ9fQ==--4e27bac8cdfb621fb828f6a3a5982fe1a423b516/16_DI_MCP23017_7.jpeg)
![16 Channel I2C 24VDC Digital Input Module](https://lectronz-images.b-cdn.net/lectronz/active_storage/representations/proxy/eyJfcmFpbHMiOnsiZGF0YSI6Njg4OTksInB1ciI6ImJsb2JfaWQifX0=--644fb94658e3fa7e1f32fe533c8d7394c84307e8/eyJfcmFpbHMiOnsiZGF0YSI6eyJmb3JtYXQiOiJqcGVnIiwicmVzaXplX3RvX2xpbWl0IjpbOTYwLDY0MF0sInNhdmVyIjp7InN0cmlwIjp0cnVlfX0sInB1ciI6InZhcmlhdGlvbiJ9fQ==--4e27bac8cdfb621fb828f6a3a5982fe1a423b516/16_DI_MCP23017_8.jpeg)
![16 Channel I2C 24VDC Digital Input Module](https://lectronz-images.b-cdn.net/lectronz/active_storage/representations/proxy/eyJfcmFpbHMiOnsiZGF0YSI6Njg5MDMsInB1ciI6ImJsb2JfaWQifX0=--3917f425e6e6d302e6ae3647fb2bf0db94adcb04/eyJfcmFpbHMiOnsiZGF0YSI6eyJmb3JtYXQiOiJqcGVnIiwicmVzaXplX3RvX2xpbWl0IjpbOTYwLDY0MF0sInNhdmVyIjp7InN0cmlwIjp0cnVlfX0sInB1ciI6InZhcmlhdGlvbiJ9fQ==--4e27bac8cdfb621fb828f6a3a5982fe1a423b516/16_DI_MCP23017_9.jpeg)

## Description

**What is it?**

This is a 16-channel industrial digital input module designed for 24VDC systems, based on the MCP23017 I2C GPIO expander.

Unlike typical low-voltage GPIO boards, this module is built for real-world applications, allowing you to directly interface with 24V sensors, switches, and control signals.

Each input is opto-isolated and conditioned, providing reliable and noise-resistant signal acquisition for embedded systems and industrial control panels.

**Why this board is different**

Most I2C GPIO expanders:
- Operate at 3.3V / 5V only
- Require external signal conditioning
- Are not suitable for industrial environments

This board solves that by providing:
- Direct 24VDC input compatibility (PNP / sourcing signals)
- Opto-isolation between field and logic
- Integrated protection (TVS, reverse polarity)
- Per-channel filtering for noise reduction

This allows direct connection to real industrial signals without additional interface circuits.

**Key Features**
- 16 × 24VDC digital inputs (PNP / sourcing)
- Opto-isolated inputs (field side isolated from logic side)
- MCP23017 I2C interface (3.3V logic)
- On-board 24V → 3.3V regulator
- Per-channel input protection and filtering
- TVS surge suppression + reverse polarity protection
- Interrupt outputs (INTA / INTB)
- Reset signal access
- Configurable I2C address (up to 8 modules)
- I2C IN / OUT connectors for daisy-chaining
- Optional onboard I2C pull-ups

**Electrical Characteristics**
- Input voltage: 24VDC nominal
- Input type: PNP (sourcing)
- Detection levels:
- ON ≥ 12V (recommended)
- OFF ≤ 5V
- Input current: ~6.8 mA per channel @ 24V
- Logic interface: I2C (3.3V)

**Typical Applications**
- PLC and embedded controller input expansion
- 24V sensor interfacing (proximity sensors, limit switches, etc.)
- Industrial control panels
- Alarm and status monitoring systems
- Remote / distributed I/O systems

**Integration**
- Connect 24V signals directly to input terminals
- Communicate via I2C
- Daisy-chain multiple modules (up to 8 boards)

Designed to work seamlessly with STM32, ESP32, and other microcontrollers.

**Important Notes**
- Designed for 24VDC industrial systems only
- Inputs are PNP (sourcing type)
- Field side is opto-isolated from logic side
- Do not exceed intended input voltage levels
- Power down before wiring changes