Microchip Technology Inc

Linear Regulators with Low Dropout LDO Voltage

Choosing the right linear regulator is critically important. Power management is vital in a world driven by smaller devices reliant upon batteries that require efficient power consumption and precision.

Microchip's linear low dropout LDO regulators feature ultra-low quiescent current, ultra-low dropout voltage, ultra-high ripple rejection, very accurate output, fast transient response, wide selection of packages and wide input voltage range.


What are linear low dropout regulators?

Linear Low Dropout Regulators (LDO) are a simple solution for regulating a higher voltage to a lower voltage through an integrated circuit without the use of an inductor. LDOs span a wide spectrum of specialized uses and can be widely implemented in today’s electronics because of their simplicity and low cost.

Why use linear low dropout regulators?

Today, as battery operated devices drive nearly every aspect of everyday life, LDOs prove to be an effective tool in achieving low power consumption and high power efficiency. Many other types of regulators exist on the market but, in many cases, linear dropout regulators prove to be the most cost-effective solution to modern power regulation. The lack of a large and expensive inductor allows LDOs to achieve a much smaller footprint and higher overall value when considered from a cost/benefit perspective. LDOs are a straightforward and cost-effective solution to linear power regulation.

How do you choose the right low dropout linear regulator?

With such a large variety of LDOs available in today’s market it could become difficult to identify the optimal LDO for customer applications. Here are four important characteristics to consider before selecting an LDO:

Low Dropout: This is the main purpose of the linear low dropout regulator. Though there are many ways to utilize an LDO, maintaining a low dropout between the input and output voltage is the LDO’s primary purpose. This is an important aspect to consider before choosing an LDO as a power regulation solution.
Accuracy: As the performance and capability of technology today continues to grow at a rapid rate, it is crucial that the core components of these devices meet stringent requirements and operate on a consistent and leading-edge basis. The LDO’s responsibility is not only to have a low input to output dropout but also to ensure that the voltage is outputted with the smallest margin of error. 

Power Supply Rejection Ratio (PSRR): In the process of dropping input voltage to output voltage, various unwanted frequencies could find their way into the integrated circuit. The power supply rejection ratio of a linear regulator is the measurement of how well the integrated circuit filters/rejects out extraneous noise in the input voltage signal before voltage is outputted. High PSRR typically correlates to a more consistent output accuracy.

Low Quiescent Current: Also known as IQ, quiescent current is the current that is drawn from an integrated circuited while it is in a quiescent (no-load, non-switching) state. IQ can be understood as the minimal amount of current needed to power the basic functionalities of a device. The lower the rated quiescent current of a linear regulator, the more power efficient the linear regulator is in a no-load state.

Key features of low dropout linear regulators
  • Output currents range from 10 mA to 7.5A with multiple outputs
  • Wide selection of packages from 1x1 mm DFN packages to TO-263
  • Ultra-low dropout voltage of 40 mV at full load
  • Ultra-high ripple rejection ratio of 90 dB+
  • Very accurate output of 0.4% typical
  • Ultra-low quiescent current of 20 nA typical
  • Wide input voltage up to 120V

LDO Product Types

Single Output LDO Regulator

Single output of regulated voltage with your choice of fixed or adjustable output.

Multiple Output LDO Regulator

Multiple output of regulated voltage of fixed output.

Ripple Blocker

LDO with low-pass filter in one package for high PSRR for various frequency ranges.

LDO Controller & SIM Card Products

LDO controller includes all the control functions required in the design of low dropout linear regulator (LDO). 

SIM card level shifter integrates three high-speed level shifters for SIM card signal translation and an LDO to power the SIM card.

Need help choosing the right linear regulator? Try our new Product Advisor tool.

Featured LDO Products:


A small LDO with immense functionality. The MIC5306 provides ultra-fast transient response and high PSRR while operating with an ultra-low quiescent current.

  • 16µA Operating Current
  • High Output Accuracy of ±1%
  • Low 45mV dropout at 100mA
  • Input voltage ranging from 2.25V to 5.5V