The Components You Need for Industrial Control Design

Some manufacturing operations have seen major benefits from automation and robotics, and systems for industrial automation require control and data acquisition systems. If a facility is to run at peak efficiency, the automation and control systems must be designed with reliability and visibility in mind. These systems require a range of components spanning from panel-mounted controllers to small embedded boards with a mix of sensors and ICs.

If you’re designing boards for industrial control systems, there are some common components you’ll find are essential for your product. These components are meant to perform all the essential data/signal acquisition tasks, as well as processing and generation tasks that are needed as part of a larger control system. Whether you’re doing a box build or a small board for a control and monitoring system, here’s where you can find the components you’ll need.

Essential Components for Industrial Control Design

The components you need for industrial control design can be divided into different categories b functionality. At a high level, these systems need to generate and gather signals within a larger control system, and they may need to process data as part of a control algorithm. Your industrial control board might also need to communicate wirelessly, manage power to peripherals, and stand up to high temperatures. Without further delay, here are some functional aspects you’ll need to consider when designing boards for industrial control.

Power Regulation

This is a basic requirement for any system for industrial applications. A board for an industrial control or monitoring system may require power up to 24 V, and a single board may require multiple levels to function properly. Power supply modules may also need to supply high current, particularly if being used to run an electromechanical or electrothermal element. You can find a range of switching converters or LDOs that are ideal for low power applications. A larger module like the Mean Well IRM-03-12S AC/DC regulator is designed for higher power industrial systems.

Mean Well IRM-03-12S AC/DC power regulator and block diagram. Source: IRM-03-12A datasheet.

Board Identification

Before my company started getting calls from automation facilities looking for board layout services, the last time I heard anyone discuss EEPROMs was when referring to Arduino. If multiples of your board will appear in a larger system, or if you’re releasing a board as part of a product line, the board needs a unique identifier that can be accessed electrically. Enter EEPROMs, which allow a unique identifier to be loaded onto the board.

More advanced products may use an MCU/SoC that integrates Flash memory with wireless capabilities and multiple I/Os. These components will have a MAC address that serves as a unique identifier, so an EEPROM won’t be necessary in this case. Experimental mesh networks of IoT devices for industrial monitoring are going this route as these integrated MCU/SoC reduce total part count and cost. 

Data Acquisition and Signal Generation

These two inverse functions are implemented with an ADC (acquisition) and DAC (generation). For industrial applications, ADCs typically don’t need to have a very high sample rate as you’re not often working with very high frequencies. However, for measurement and signal generation, you need to ensure the resolution is sufficiently high for your application. You should also check the number of channels as you may need to interface with multiple components.

If you need to generate a clean sine wave or square wave at low to moderate frequencies, you might be better off with an oscillator IC or a custom-built oscillator, depending on the frequency range you need. The LTC1799 from Linear Technologies comes in a small package and outputs from 1 kHz to 33 MHz with 2.5% frequency tolerance. This oscillator and many others come in a small package and have simple implementation (see below).

LTC1799 1 kHz to 33 MHz oscillator. Source: LTC1799 datasheet.

Processing Power

Once you collect some data, you need to do something with it. An MCU, FPGA, or other PLD gives you the processing power you need as well as other useful peripherals in a single component. The typical use of collected data in industrial control is as part of a control loop. This application doesn’t necessarily require huge clock rates; something in the MHz range should be plenty for most applications. You might need to opt for high on-board memory, depending on the size and complexity of your application.

4-20 mA Current Loop Generation

If you’re working with the de facto 4-20 mA standard, then you’ll need a driver to generate a current loop for your process control system. Motor drives, PLC output programmable drivers, high voltage I/Os, and sensors on a linear bus all make use of these control loops. The XTR305 analog driver from Texas Instruments is a precision condition for a 4-20 mA loop driver or +/- 10 V driver, which could be sourced from a DAC. This component also has a receiver mode for control loop applications, which eliminates the need to use an ADC channel for measurement.

XTR305 block diagram. From the XTR305 datasheet.

Amplifiers

You may need a range of amplifiers in your system, depending on the voltage ranges you need to read and the required bandwidth. General-purpose op-amps or instrumentation amps are useful for amplifying a low-level signal before sampling with a DAC, or for stepping up an analog voltage signal without a bulky transformer. Some amplifiers are specifically designed to target industrial applications and will be more rugged than a typical op-amp IC.

ESD Protection

Industrial systems may be operating near high voltage, and critical systems may require ESD safety. Multiple circuit protection components are useful here, depending on the peak voltage and rise time to which the board might be exposed. Examples include simple fuses, relays, TVS diodes, and gas discharge tubes.

Other Components for Industrial Control Design

Obviously, the list of components needed for industrial control boards is huge, but the options listed above are highly likely to make an appearance in your next board. Some other components you might need for your next industrial control design include:

• Programmable logic controllers

• Interface ICs

• Wireless components (WiFi, Bluetooth, etc.)

• Single-board computers

No matter which components you need for industrial control design, you can use the advanced search and filtration features in Octopart to find the parts you need. When you use Octopart’s electronics search engine, you’ll have access to distributor data and parts specifications, all of which is freely accessible in a user-friendly interface. Take a look at our linear integrated circuits page to find the components you need.

Stay up-to-date with our latest articles by signing up for our newsletter.