Digital inputs and outputs

Design a complete I/O solution for your PLC and industrial control systems

Design your system from start to finish with our portfolio of I/O architectures

Digital input/output (I/O) modules are essential for factory and process automation, providing vital connections to a wide range of sensors and actuators. On the input side, they connect to simple push buttons, proximity switches and high-speed digital encoders. Similarly, on the output side, I/O modules drive simple light bulbs, relays, contactors, actuators and motors. Our portfolio will help you find a competitive solution for isolated or nonisolated architectures for programmable logic controllers (PLCs) and industrial control systems. 

Digital I/O architectures

Isolated digital inputs for power-efficient, high-density automation solutions

Isolated digital inputs provide galvanic isolation between a sensor input (or other input type) and a logic output for a host controller interface. When compared to traditional optocoupler solutions, our isolated digital input devices provide a simple low-power alternative with an accurate current limit.

With solutions providing up to eight channels, TI's isolated digital inputs provide substantial space savings and lower design complexity. This alternative to optocouplers enables the design of compact and high-density PLC I/O modules.

Benefits:

  •  Minimize bill of materials and board space
  • Lower design complexity
  • Reduce system power dissipation

Learn more about our digital input portfolio:

Download
Application brief
Digital Input Module, Digital Output Module
This application brief shares how to build an eight-channel configurable digital I/O module using a standard high-side switch output and standard digital input devices.
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Application brief
How To Simplify Isolated 24V PLC Digital Input Module Designs (Rev. C)
This application brief explains the methods for improving a design of digital input modules used in PLCs and motor drives.
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Reference design
Broken Wire Detection Using An Optical Switch
This reference design shows a compact implementation of 16 isolated digital input channels using ISO1211, ISO1212 and ISO1228 devices.
Featured products for Digital inputs
NEW ISO1228 ACTIVE Eight-channel isolated 24-V to 36-V digital input receiver with current limiting and LED indication
ISO1212 ACTIVE Dual-channel Isolated 24-V to 60-V digital input receiver for digital input modules
ISO1211 ACTIVE Single-channel Isolated 24-V to 60-V digital input receiver for digital input modules

High-side switches for driving and protecting loads

Our portfolio integrates protection and diagnostics to reliably drive resistive, capacitive or inductive loads in PLC digital outputs. For motors or long cables, our switches internally clamp the drain-to-source voltage to demagnetize load inductance. For safety modules, we offer 60V operating voltage tolerance and support for surge and electrical fast transient (EFT) standards.

Beyond the factory, wide operating ranges and external switch controller options support digital output driving motor drives, off-highway vehicles, energy storage and EV charging.

Features:

  • Adjustable current limit
  • Output clamp to demagnetize inductive loads
  • Wire-break and short-to-supply detection
  • Accurate current sensing and ADC

Learn more about our high-side portfolio:

Technical article
Decrease factory downtime in 24-VDC power distribution with advanced load diagnostics
Learn how a high-side switch with an integrated ADC simplifies current sensing and load diagnostics to enable fast problem resolution.
PDF | HTML
Video
Power the factory floor with TI high-side switches
Watch how Serial Peripheral Interface configurable high-side switches distribute 24V across multiple offboard loads with only a single microcontroller.
Application brief
Digital Input Module, Digital Output Module
This application brief describes how to build an eight-channel configurable digital I/O module using a standard high-side switch output and standard digital input devices.
PDF | HTML
Featured products for High-side digital outputs
TPS274C65 ACTIVE 12-V to 36-V 65-mΩ four-channel high-side switch with SPI interface and integrated ADC
TPS281C30 ACTIVE 60V-tolerant, 30mΩ 6A single-channel high-side switch
TPS281C100 ACTIVE 6-V to 60-V, 100-mΩ, 4.5-A single-channel high-side switch

Low-side switches drive efficient and reliable systems

In PLC digital output modules, low-side switches control the flow of current to a load by switching the low side of the power supply. This module is typically used in applications that need to convert a digital signal into an analog output.

Our low-side switch design provides a redundant path to the load, with fault tolerance, as it can handle high currents and voltages up to 70V.

Benefits:

  • High reliability
  • Low power consumption
  • Optional external clamps
  • Easy integration

Learn more about our low-side portfolio:

Download
Application note
Using DRV to Drive Solenoids (Rev. A)
This application note discusses primary considerations when driving solenoids.
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Reference design
High speed digital output PLC module reference design
This reference design highlights our low-side switches for PLC applications.
Application note
Understanding Motor Driver Current Ratings (Rev. A)
This application note explains the different current ratings applied to motor-driver parts.
PDF | HTML
Featured products for Low-side digital outputs
DRV8803 ACTIVE 60V, 2.3A 4 channel low-side driver with PWM control and overcurrent protection
DRV8804 ACTIVE 65V, 2.3A 4 channel low-side driver with integrated SPI and overcurrent protection
DRV120 ACTIVE 28V, 0.25A single channel relay low side driver with current regulation

Push-pull digital outputs for precise and efficient control

Our push-pull digital output portfolio offers bidirectional control for precise automation tasks by combining high- and low-side switching in a single configuration. Our portfolio provides efficient sourcing and sinking of current, enabling fast, accurate motion control for motors, actuators and other high-performance applications. Achieve responsive, reliable operation, designed to optimize power delivery and streamline industrial processes.

Benefits:

  • High power efficiency
  • Bidirectional control
  • Reliability
  • Overcurrent protection

Learn more about our push-pull portfolio:

Download
Featured products for Push-pull digital outputs
DRV8800 ACTIVE 40-V, 2.8-A brushed DC motor driver
DRV8844 ACTIVE 60V, 2.5A dual H-bridge motor driver, bipolar (+/-30V) supply and independent 1/2-bridge control
DRV8955 ACTIVE 50-V, 2.5-A, quad half-bridge driver with current sense

Choose your digital input and output solution

Featured reference designs for digital I/O

Reference design
96-Channel Bidirectional Digital Input Module Reference Design for PLC
This reference design is a compact implementation of 96 isolated digital input channels using the ISO1212, an isolated digital input receiver. This design shows the current limit feature of the ISO1212 device which has better thermal performance than traditional optocoupler solutions. This design (...)
Reference design
High Speed Digital Output PLC Module Reference Design
This high-speed digital output reference design for programmable logic controllers (PLCs) illustrates low-cost, simple high-speed single-ended digital output module using standard low-side driver and backplane powered using isolated power stage. High-speed digital output modules are required for (...)
Reference design
8-ch Parallel 0.5A Low Side Digital Output Module for PLC Reference Design

Digital Output Modules are a standard component in a PLC/PAC or DCS to control actuators, motors and other resistive, capacitive or inductive loads. Customers will benefit from this integrated protected low side driver with parallel interface as it makes the MCU interface easy to test together with (...)