Low Quiescent Current LDO: ETEK Micro ET5H5XX | ETEK

With the rapid development of smart electronics, IoT devices, and portable equipment, power management solutions are required to achieve higher efficiency, lower power consumption, and more stable voltage regulation. Traditional linear regulators may consume excessive quiescent current during low-load or standby conditions, making them less suitable for battery-powered applications.

A low quiescent current LDO is designed to minimize internal power consumption while maintaining stable output voltage. By reducing quiescent current consumption, it helps extend battery life and improve overall system efficiency.

ETEK Micro introduces the ET5H5XX series, a high-voltage low quiescent current LDO regulator featuring a wide 3.0V to 40V input voltage range, 300mA output current capability, and ultra-low 2.8µA quiescent current. Based on advanced CMOS technology and PMOS pass transistor architecture, the ET5H5XX provides low noise, fast startup, excellent transient response, and reliable voltage regulation for various electronic applications.

What Is a Low Quiescent Current LDO?

A low quiescent current LDO is a low dropout linear regulator designed to minimize its own quiescent current while maintaining stable output voltage.

Quiescent current refers to the current consumed by the regulator’s internal circuits when the regulator is enabled and operating under no-load conditions. In many battery-powered devices, the system spends most of its time in standby mode, meaning the regulator’s own power consumption can significantly affect battery life.

Compared with conventional LDO regulators, a low quiescent current LDO reduces unnecessary energy loss and provides better efficiency for applications requiring long operating time.

Typical applications include:

● Battery-powered devices

● Smart wearable electronics

● IoT sensors

● Wireless communication modules

● Portable medical equipment

Why Choose a Low Quiescent Current LDO?

Lower Standby Power Consumption

For portable and battery-operated products, every microamp matters. A regulator with high quiescent current continuously consumes additional power even when the system is idle.

The ET5H5XX achieves an ultra-low quiescent current of only 2.8µA, helping designers reduce standby power consumption and extend battery operating time.

Stable Output Voltage with High Efficiency

A high-performance LDO should provide stable voltage regulation under different operating conditions.

The ET5H5XX combines low dropout characteristics with excellent load and line transient response, ensuring stable power delivery even when input voltage or load conditions change.

ETEK Micro ET5H5XX High Voltage Low Quiescent Current LDO Features

The ET5H5XX series is designed for applications that require both high input voltage capability and ultra-low power consumption.

Wide 40V Input Voltage Range

The ET5H5XX supports an input voltage range from 3.0V to 40V, providing strong flexibility for systems with unstable power supplies or high-voltage input requirements.

This makes it suitable for:

● Industrial control equipment

● Embedded systems

● Communication devices

● Smart electronics

300mA Output Current Capability

With a maximum output current of 300mA, the ET5H5XX can provide stable power for various electronic components.

The regulator supports multiple output voltage options, including:

● 1.8V

● 3.0V to 13V

This allows engineers to select suitable voltage solutions according to different application requirements.

Low Dropout Voltage and Excellent Transient Response

The dropout voltage is an important parameter for LDO performance. A lower dropout voltage allows the regulator to maintain stable output even when the input voltage is close to the output voltage.

For the ET5H5XX:

● Output voltage: 5.0V

● Load current: 300mA

● Typical dropout voltage: 1000mV

In addition, the device provides excellent load transient and power transient response, helping maintain system stability during rapid load changes.

High Ripple Rejection Performance

Power supply noise can affect sensitive electronic circuits. The ET5H5XX provides strong noise suppression capability with:

● Ripple rejection: 52dB at 1kHz

This feature helps deliver cleaner power for applications that require reliable voltage regulation.

Applications of ET5H5XX Low Quiescent Current LDO

Due to its low power consumption, high input voltage capability, and stable performance, the ET5H5XX can be widely used in different electronic systems.

Portable Electronics

Battery-powered devices require efficient power management to achieve longer operating time. The ultra-low quiescent current design makes ET5H5XX suitable for portable equipment and compact electronic products.

IoT and Wireless Devices

IoT products often require long standby operation and reliable power supply. A low quiescent current LDO helps reduce energy waste and improve system endurance.

Industrial Applications

Industrial equipment may experience voltage fluctuations and demanding operating conditions. The 40V input capability of ET5H5XX provides additional design flexibility and reliability.

Multiple Package Options for Flexible Design

To meet different PCB design requirements, the ET5H5XX series provides multiple package options:

● SOT89-3

● SOT23-5

● SOT23-3

● DFN4 (1×1)

The series also supports versions with or without EN (Enable) function, allowing engineers to optimize system power control according to application needs.

Conclusion

As electronic devices continue to pursue lower power consumption and longer battery life, the demand for efficient power management solutions continues to increase.

A low quiescent current LDO provides an effective solution by minimizing standby power consumption while maintaining stable voltage output.

ETEK Micro’s ET5H5XX series combines:

● 40V high-voltage input capability

● 300mA output current

● 2.8µA ultra-low quiescent current

● Low dropout performance

● Excellent transient response

● Multiple package options

With these advantages, the ET5H5XX is an ideal low quiescent current LDO regulator solution for portable electronics, IoT devices, wireless communication systems, and industrial applications.

Learn more about the ET5H5XX high-voltage LDO series: https://www.etekmicro.com/products/power-management/ldo/high-vin-ldo/et5h5xx/

Sample Request: https://www.etekmicro.com/sample