Last revised: September 10, 2024
Reviewed by Scott Orlosky, consulting engineer

IC voltage regulators are three-terminal devices that provide a constant DC output voltage that is independent of the input voltage, output load current, and temperature.

Types of IC Voltage Regulators

There are three types of IC voltage regulators: IC linear voltage regulators, IC switching voltage regulators, and DC/DC converter chips. 

• IC linear voltage regulators use an active pass element to reduce the input voltage to a regulated output voltage.
• By contrast, IC switching voltage regulators store energy in an inductor, transformer, or capacitor and then use this storage device to transfer energy from the input to the output in discrete packets over a low-resistance switch.
• DC/DC converter chips, a third type of IC voltage regulators, also provide a regulated DC voltage output from a different, unregulated input voltage.

In addition, DC/DC converters provide noise isolation regulate power buses. For each type of IC voltage regulator, the output voltage can be fixed or adjusted to a value within a specified range.

Performance Specifications

Performance specifications for IC voltage regulators include:

• The regulated output voltage (V_olt) represents minimum and maximum amounts in continuous mode (DC). Output voltage can be fixed, or adjustable.
• The output current (I_OUT) is measured under specified conditions.
• Dropout voltage (V_D) is the minimum voltage drop across the regulator that maintains output voltage regulation. IC voltage regulators that operate with small dropout voltages dissipate less internal power, but have relatively high efficiencies.
• Measured in amperes (A) during the idling state, the quiescent current never makes it to the load. Instead, it flows from the battery to power the regulator itself.
• The operating temperature is a full-required range.

Features

IC voltage regulators are available with a variety of features.

• Multiple outputs or channels
• Internal circuit to control the amount of current produced
• An error flag for monitoring outputs that drop below a nominal value.
• Reverse voltage protection prevents damage in applications where users can accidentally reverse battery polarity.
• Thermal shutdown protection turns off IC voltage regulators when the temperature exceeds a predefined limit.
• Shutdown (inhibit) pins are used to disable regulator outputs. 

Packaging

 IC voltage regulators are available in a variety of IC package types. Dual in-line packages (DIP) can be made of ceramic (CIP) or plastic (PDIP). Quad flat packages (QFPs) contain a large number of fine, flexible, gull wing shaped leads. SC-70, one of the smallest available IC packages, is well-suited for applications where space is extremely limited. Small outline (SO) packages are available with 8, 14, or 20 pins.

 Transistor outline (TO) packages are commonly available. TO-92 is a single in-line package used for low power devices. TO-220 is suitable for high power, medium-current, and fast-switching products. TO-263 is the surface-mount version of the TO-220 package. Other IC packages for IC voltage regulators include shrink small outline package (SSOP), small outline integrated circuit (SOIC), small outline package (SOP), small outline J-lead (SOJ), discrete package (DPAK), and power package (PPAK).

IC Voltage Regulators FAQ

How do different types of IC voltage regulators compare in terms of efficiency and performance?

Linear regulators are relatively simple and inexpensive. They are noise-free. They generally exhibit low power efficiency because they dissipate excess power as heat. This is particularly true when the difference between input and output voltage is large. They are typically used for stepping down voltage and are often used in applications where low noise is critical.

Switching regulators are more complex and relatively expensive. They tend to be noisier due to the switching action. They have high power efficiency and can be used for both stepping down and stepping up voltage. They are more efficient than linear regulators, especially when the input voltage is significantly higher than the output voltage. They are suitable for applications requiring high efficiency and where the input voltage can vary widely.

What are some key performance specifications to consider when selecting an IC voltage regulator for a specific application?

• Input Voltage Range: The range of input voltages that the regulator can accept. This is crucial to ensure compatibility with the power source.
• Output Voltage: The regulated output voltage, which can be fixed or adjustable within a specified range.
• Output Current (IOUT): The maximum current the regulator can supply to the load.
• Dropout Voltage (VD): The minimum voltage difference between the input and output that the regulator can maintain while still regulating the output voltage.
• Efficiency: The ratio of output power to input power, which is important for power-sensitive applications.

What are some common applications for IC voltage regulators?

• Consumer Electronics:

  • Smartphones and Tablets: To ensure stable power supply to various components such as processors, memory, and display.
  • Laptops and Computers: For regulating power to CPUs, GPUs, and other peripherals.
  • Televisions and Audio Equipment: To maintain consistent performance and reduce noise.

• Automotive:

  • Engine Control Units (ECUs): To provide stable voltage to microcontrollers and sensors.
  • Infotainment Systems: Ensuring consistent power to audio, video, and navigation systems.
  • Battery Management Systems: For regulating voltage in electric and hybrid vehicles.

• Industrial Equipment:

  • Robotics: To supply stable power to motors, sensors, and control systems.
  • Automation Systems: Ensuring reliable operation of PLCs (Programmable Logic Controllers) and other control devices.
  • Power Supplies: Used in various industrial power supply units to provide regulated output.

• Medical Devices:

  • Portable Medical Equipment: Such as blood glucose meters and portable ECG monitors, which require stable power for accurate readings.
  • Imaging Systems: Ensuring consistent power to sensitive imaging equipment like MRI and CT scanners.

• Telecommunications:

  • Base Stations: To provide stable power to communication equipment.
  • Networking Devices: Such as routers and switches, which require regulated power for reliable operation.

• Energy Harvesting Systems:

  • Wireless Sensor Networks (WSNs): To manage power harvested from environmental sources like solar or thermal energy.
  • Remote Monitoring Systems: Ensuring stable power supply to sensors and communication modules in remote locations.

• Embedded Systems:

  • Microcontroller-Based Projects: Providing stable voltage to microcontrollers and associated peripherals.
  • IoT Devices: Ensuring reliable operation of sensors, actuators, and communication modules.

What are the common package types for IC voltage regulators?

IC voltage regulators come in various package types, including Transistor Outline (TO) packages like TO-92, TO-220, and TO-263. Other packages include Shrink Small Outline Package (SSOP), Small Outline Integrated Circuit (SOIC), Small Outline Package (SOP), Small Outline J-lead (SOJ), Discrete Package (DPAK), and Power Package (PPAK)

What is the difference between a fixed and an adjustable voltage regulator?

Fixed voltage regulators provide a constant output voltage regardless of changes in the input voltage or load conditions. Adjustable voltage regulators, on the other hand, allow the output voltage to be set to a desired level using external resistors.

How do you determine the dropout voltage of a voltage regulator?

Dropout voltage is the minimum difference between the input voltage and the output voltage at which the regulator can still maintain the specified output voltage. It is an important parameter for low-voltage applications.

What are the thermal considerations for IC voltage regulators?

Thermal performance is crucial for IC voltage regulators. It includes factors like thermal resistance, junction temperature, and the need for heat sinks or other cooling mechanisms to ensure reliable operation under various load conditions.

What are the protection features commonly found in IC voltage regulators?

Common protection features include overcurrent protection, thermal shutdown, and short-circuit protection. These features help prevent damage to the regulator and the load in case of fault conditions.

How do you select the appropriate capacitor values for an IC voltage regulator?

The selection of input and output capacitors is critical for the stability and performance of the voltage regulator. Manufacturers typically provide recommended capacitor values and types in the datasheet to ensure optimal performance.

Standards

CECC 90201 - Specification for harmonized system of quality assessment for electronic components.
MIL - M - 38510/107 - Specification for microcircuits, linear, positive, voltage regulators, and monolithic silicon.
QPL-23761 - Qualified product list for products under performance specification MIL-R-23761 Regulators, voltage, and control panels aircraft.

IC Voltage Regulator Media Gallery

References

Electronics360: How to select a voltage regulator
Electronics360: Power Management for Energy Harvesting in WSNs
Electronics360: DC-DC Voltage Regulators: Key to Reliable Circuit Performance
GlobalSpec: IC Switching Voltage Regulator Learn More

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 M.S. Kennedy Corp. | Circuitstoday.com | ROHM Semiconductor USA LLC