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The purpose of power management is to optimise electronic system performance and improve reliability.

With a growing demand for energy efficiency, power consumption adjustment to match real-time system demands is increasingly important.

This article provides an overview of power management techniques. It outlines the significant role resistors play in power management systems.

Power Management Overview

Power management is input power conversion from a source into appropriate voltage levels for different system elements. The aim is to optimise system performance, improve reliability and energy efficiency

Power management includes the delivery of power to system elements in the correct order during startup and shutdown.

It includes improving reliability by protecting sensitive components from power supply fluctuations. Thermal management to increase component reliability also falls under the power management banner.

Energy efficiency is becoming an important element of power management. A common solution is to dynamically adjust power consumption based on real-time system requirements.

Resistors In Power Management Applications

Resistors play a key role in regulating, protecting, and optimising power in electrical circuits.

Performance

One of the most common applications of resistors in power management is voltage dividers. The total voltage is divided across resistors in proportion to their resistance values.

This precise control of voltage levels facilitates matching the voltage to system requirements. This improves energy efficiency and minimises power wasteage.

Resistors, in combination with capacitors, form RC filters. These filter out unwanted noise from power lines or signal inputs. This maintains signal integrity and improves energy efficiency. It also prevents high-frequency noise from affecting the performance of sensitive electronic components.

In analogue circuits, resistors provide biassing to transistors, operational amplifiers, and active devices. This approach minimises distortion and maximises energy efficiency in amplifiers and power modules.

In feedback networks, resistors help set output voltages and adjust feedback loops. Their purpose is to ensure power supplies adapt to changing loads while maintaining a stable output. Again, this process also improves energy efficiency.

Reliability

Resistors in current limiting circuits prevent damage to sensitive components. Surge protection resistors prevent component damage by absorbing and dissipating the energy generated by voltage spikes.

Energy

Battery management systems use resistors for balancing the charges of individual cells. Hence, each cell discharges and charges at an equal rate maximising the energy efficiency of the battery pack.

Resistor Selection & Custom Resistors

We cover resistor selection across several resistor technologies elsewhere on this blog. Wherever possible, the best option is to select a standard resistor device from one of the major resistor manufacturers.

However, where it is impossible to compromise on safety, reliability, performance, energy efficiency or longevity and a standard device is not suitable, a custom resistor solution may be the best option.

We cover the advantages and potential disadvantages of custom resistor solutions elsewhere in this blog.

Advantages of Thick Film Resistors in Power Management

Many resistor technologies are available. For power applications wirewound resistor, ceramic resistor, foil resistor and thick film resistor technologies are most common.

Each resistor technology has advantages and disadvantages, but the default general-purpose solution is often thick film. The technology is durable and reliable and is relatively small compared to other technologies. Its electrical and high-temperature performance is adequate in most applications.

Thick film resistors can utilise heatsinks to increase heat dissipation (and hence power handling) performance. They can be designed and manufactured to fit within specific dimensions and are surface-mount compatible.

If a custom thick film power resistor is the only choice, specialist manufacturers work closely with design and system engineers to deliver a resistor device that matches exacting specifications. They often supply prototypes for approval and manufacture in low to medium volumes.

In summary, resistors are indispensable components in power management systems. As energy efficiency becomes more important, careful selection of resistors will remain critical in these applications.

While various resistor technologies exist, thick-film resistors often emerge as the preferred choice. This is due to their durability, compact size, and high-temperature performance. If standard resistors do not match the specification, custom thick-film resistors are one possible solution.