PMIC - Voltage Regulators – DC-DC Switching Regulators
A voltage regulator is an electrical device that maintains the voltage of a power source at a required voltage. The voltage regulators effectively keep the voltages in the recommended range of the electrical equipment receiving those voltages. Such devices are utilized in motor vehicles of all types to match the output voltage of the electrical generator and the electrical load and to the charging needs of the battery. These devices are also effectively used in electrical equipment where frequent voltage changes will be damaging. Therefore, it can regulate voltage during fluctuations and variations in load. It is useful for regulating both AC and DC voltage. They can take high input voltages and give out more stable or lower voltages. A secondary use for them is to protect the circuits during voltage spikes that can lead to severe damage.
Types of Voltage Regulators
Voltage regulators utilized in low-voltage electronic gadgets are typically integrated circuits. Power appropriation focuses on giving AC capacity to residential and industrial shoppers to utilize more refined and precisely enormous voltage regulators that keep up with appraised 110 V voltage paying little mind to utilization demands across the area.
In light of the physical plan, voltage controllers should be visible in coordinated circuits, electromechanical gadgets, or solid-state automated regulators. The most widely recognized characterizations of the active voltage regulators are linear and switching regulators.
Linear Regulators
Linear regulators are simple transistor-based devices that are usually packed as integrated circuits. They use differential amplifiers in their internal circuits to manage the output voltage against the reference voltage. Linear voltage regulators may give a fixed output or have a certain degree of adjustable control. They would require input current equal to the output current.
Switching Regulators
A switching regulator is a circuit that utilizes a power switch, a diode, and an inductor to change energy from input to output. They can toggle a device ON/OFF high frequency and change the duty cycle of the voltage transferred as output. The common topologies of these regulators are a buck, boost, and buck-boost. Buck converters are considered more effective during the voltage step down and can still increase the output current. The boost converters, on the other hand, can increase the output voltage to an amount more than the input voltage.
The power switch used by these regulators is usually a Field Effect Transistor controlled by a switching controller IC that evaluates the output of the switching regulator in a feedback control loop. This ensures it maintains a constant voltage output when operating under normal conditions. Often in switching regulators, the FET is designed as a discrete component placed externally to the switching controller. In other designs, you will find the FET and controller in the same Integrated Circuit.
Why Prefer Switching Regulators Over Linear Regulators?
Switching regulators provide three key advantages compared to linear regulators:
- They offer much better switching efficiency.
- Less energy loss occurs during the transfer, and smaller components and minimum thermal management are needed.
- They can transform the energy stored by an inductor in a switching regulator into voltages greater than the input, are negative, or even through a transformer to offer electrical isolation per the input.
Given such advantages, switching regulators are highly preferred over linear regulators. However, linear regulators also provide lower noise, higher bandwidth, and a simple design, making them the less expensive option.
