Programmable Power Supplies

Power supplies provide electrical energy in the form of operating voltage to power a wide range of systems, delivering stable, precise, and clean power to support different processes. These electronic, physical, or chemical processes create other forms of energy like heat, light, and electromagnetic fields or run electronic circuits, motors, pumps, etc. All these processes have some kind of variance. 

A "fixed" power supply offers the same performance in almost all applications with a limited ability to adjust settings. On the other hand, a programmable power supply is adjustable through a program, such as software or firmware, to tackle diverse requirements and enable other features like a remote control. In many applications, having a smart power supply can greatly expand the capabilities and efficiency of your system.

Explore our air-cooled or liquid-cooled programmable power solutions

What Is a Programmable Power Supply?

While traditional power supplies are fixed or give you few options, programmable power supplies offer more flexibility and multiple operating modes. These digitally controlled power sources offer control over different settings, including variable voltage, current, power, and mode of operation. The user can adjust these settings as needed.

Engineers and technicians benefit from this flexibility in certain applications where demands exceed standard offerings

• Working with an application with an unknown or variable voltage requirement.
• Working with a unique voltage not found in the standard voltages of off-the-shelf power supplies.
• The need to vary voltage dynamically through the process.
• Change operating modes between processes 

Programmable power supplies can tackle these requirements by enabling switching between various operating modes. For example, a smart charger with a programmable power supply can charge a battery by supplying constant current (CC) initially and then switching to constant voltage (CV) as the battery nears full charge. Then, if the power supply exceeds the user's current limit setting in CV mode, it can automatically switch back to CC mode.

In CC mode, the power supply regulates the current. This is typically considered the "safety" mode, but it can also be used in other ways. The output current is constant and determined by the user's current limit setting. In CV mode, the power supply controls the output voltage, which is constant, and user determined.

In some chemical processes, the power supply needs to deliver a pre-determined set of power, also called constant power (CP). This calls for constant process monitoring and a programmable power supply that dynamically communicates with the control system. Programming is achieved by the controller, and the power supply responds to these commands. This kind of power supply can even have a controller built-in, where the user simply writes and runs a program that fits their process. A standard programmable power supply thus fits the user's specific, varying demands.

Is Programmable the Same as Adjustable in Power Supplies?

Many power supplies have some adjustable parameters. Programmable power supplies allow for more comprehensive adjustments and remote control. A manually adjustable power supply might need to be changed via knobs and dials, but a programmable power supply can run from computer programs and enable more sophisticated control.

How Does a Programmable Power Supply Work?

A programmable power supply is made up of many different parts, including:

• A basic power converter also called a Power supply
• Control circuit with means ability to communicate
• Processors.
• Current, voltage, and power measuring means
• Programming circuitry
• Power, voltage, and current control means
• Readback circuits for current, voltage, and power

Typically, programmable power supplies are designed to operate over a wide range of values for voltage, current, power, and speed of response. They can provide AC, DC, or both AC and DC outputs. 

Many programmable power supplies have special features to improve performance. Some options include:

• Remote monitoring and control: Computer interfaces allow users to manage power supplies from off-site.
• Overcurrent protection: Some power supplies can limit or shut down the current output if overcurrent conditions occur.
• Overvoltage protection: Similarly, programmable power supplies might limit or shut down voltages if needed.
• Temperature compensation: Devices can accommodate temperature changes to keep the power supply within optimal operating conditions.
• Short-circuit protection: Various short-circuit protection mechanisms, such as current limiting and thermal resets, can help withstand these events.

Programmable Power Supply Applications

With so many capabilities, you'll find programmable power supplies usable in a wide range of applications. Some examples include:

• Industrial processes like electroplating and laser machinery.
• Military systems such as guided laser weapons.
• Electric vehicle charging systems.
• Automated test equipment
• Equipment testing, inspection, certification, and calibration processes.
• Debugging and simulation.
• Medical diagnosis and treatment systems.
• Gas generation systems like hydrogen and helium.
• Research and development equipment testing.
• Radars and communication systems

Programmable power supplies also come in various styles and ratings. They can be modular and mounted on a floor, wall, desktop, or DIN rail mounted. 

Choosing the Right Programmable Power Supply

When it's time to pick a programmable power supply, you'll need to understand many different elements of your application. Determine your application's needs in the following areas:

• Adjustable parameters: Start by identifying which parameters need to be adjustable and what limits you'll need. Estimate the worst-case combinations.
• Modes of operations: What operation types will you need?
• Speed of response: Some applications, like mission-critical equipment, will need power supplies that can respond immediately.
• Method of control: Do you need remote or computerized control options?
• Operating environment: Depending on how you'll use the power supply, you may need additional features like temperature compensation or a certain type of enclosure.

Other factors to consider include the number of outputs you'll need and the ability to enable and disable outputs. These features can be helpful in testing environments, where they allow you to connect multiple loads to one power supply or isolate and separate them. You can run various tests without being concerned about how adjustments in one output will affect the load in another.

Once you know what you need in a power supply, provide that information to manufacturers to see what's available. Make sure their product ticks all your boxes and, if necessary, consider a custom solution built specifically for your application.

Programmable Power Supplies From Astrodyne TDI