Load switches are a simple, cost-effective way to turn on and off your power rails. Our broad portfolio includes extensive current, package, and timing options. Plus, our easy-to-use parametric search tool will quickly help you find the solution to reduce your shutdown current or reduce the BOM count in your design.

1. Fetfe O-ring
2. O-ring Fet Controller
3. Oring Fet Circuit
4. Oring Fet Controller

Flexible timing

Options include a fixed or adjustable linear rise time. This can be used to manage inrush current or power sequence loads

The charge pump is used in load switches with an N-channel FET, since a positive differential voltage between the gate and the source is needed to turn on the FET. Quick Output Discharge (QOD) is an on-chip resistor from VOUT to GND that is turned on when the device is disabled via the ON pin.

Oring-FET HOT-SWAP E. Four packages are recommended for the Oring application. The suitable choice depends on current and space requirements. D2PAK-7pin SuperSO8 CanPAK™ S3O8 footprint mm² 160 30 30 20 application current A. 40 40 40 25 Safe Operating Area (SOA). Renesas offers a broad portfolio of synchronous MOSFET drivers.

Lower power consumption

EN50155 Industrial 1-port FET PoE Injector with 30W output, M12 connector: TINJ-101GT-M12 Series: EN50155 Industrial 1-port Gigabit High Power PoE Injector,M12 connector: TSPL-101GT-M12 Series: EN50155 Industrial 1-port Gigabit High Power PoE Splitter, IEEE802.3at standard compliant, 24VDC output, M12 connector. Many modern devices and systems require power architectures with redundancy, summation of power for capacity, or selection of multiple sources. In this article, these functions generically are referred to as ORing. Systems using ORing are ubiquitous and varied in size and complexity.

For battery powered applications, we offer load switches with as low as 10nA of shutdown current.

Broad current range

Select a switch to support your low, mid or high current rails

Extensive package options

Find the package option that works best in your manufacturing environment.

Featured load switches

TPS22950

5.5-V, 2-A, 40-mΩ load switch with an adjustable current limit

TPS22918

TPS22918 is a 5.5V, 2A, 52m Ω load switch with adjustable rise time and output discharge, allowing design flexibility. Interface directly with low-voltage control signals with a small sized switch.

TPS22965-Q1

Fetfe O-ring

TPS22965-Q1 is a 5.5V, 4A, 16mΩ automotive high-side load switch with adjustable rise time & quick output discharge. This is in a small package solving your power dissipation concern.

What are load switches?

Integrated load switches from the TPS229xx family are integrated electronic relays used to turn on and off power rails. Most basic load switches consist of four pins: input voltage, output voltage, enable, and ground.

Shown below is a block diagram of a basic load switch. For a higher level of input or output power protection, check out our eFuse devices, which include features such as overvoltage shutdown, current limiting, and short circuit protection.

Hover over a block for additional information

O-ring Fet Controller

Featured literature

Basics of load switches

Learn fundamental basics of what load switches are, when they should be used, and how they can be implemented in a system.

Integrated load switches versus discrete MOSFETs

Learn about the many drawbacks and limitations of a discrete switching solution and how they can be overcome with an integrated load switch.

With an integrated load switch you can reduce solution size by 90% and greatly simplify the design process. These short videos explain what challenges you can overcome with an integrated solution.

Personalize your training experience by accessing advice and support from the integrated load switch experts. Explore our on- demand training videos, application notes, reference designs and more.

If you’re looking to reduce solution size and distribute your power, improve robustness with protection features, or diagnose against current conditions, then check out the rest of our portfolio.

EL SEGUNDO, Calif. - April 2005 - International Rectifier, IR® (NYSE: IRF), a world leader in power management technology, today introduced the IR5001S universal high-speed controller/N-channel power MOSFET driver for high-performance, active ORing circuits. The active ORing IC, housed in an SO-8 package, is used with an external MOSFET, replacing traditional diode ORing to increase efficiency and reduce power dissipation. Active ORing is a key requirement for many high-end systems requiring maximum up-time, such as carrier-class communication equipment and telecom and datacom system servers.

'Compared with typical Schottky diode ORing circuits, a system using the IR5001S active ORing IC and an optimized external MOSFET for the given power level, will reduce on-board power dissipation by up to 85%, and can be made at least 50% smaller than diode solutions. ORing circuits made with Schottky diodes run hotter for the same power level, and in many cases, this means that through-hole devices with heatsinks are needed, increasing bulk and manufacturing complexity,' said Carl Smith, Marketing Manager for Networking and Telecommunication Products at International Rectifier.

Oring Fet Circuit

As a bonus, the IR5001S provides additional diagnostic features that increase system up-time, maximizing quality of service.

Active ORing combines two or more power sources to create a redundant power source, preserving the input power supply in case one of the input sources fails. In the event of an input power failure, the active ORing circuit disconnects the non-functioning power source as quickly as possible to prevent the system bus voltage from falling, and to prevent large peak reverse currents.

Technical Highlights

The IR5001S active ORing controller IC is suitable for a wide range of active ORing circuits, including -48V/-24V input active ORing for carrier-class communication equipment, 24V/48V output active ORing for redundant AC-DC rectifiers, 12V output active ORing for multiple-output DC-DC and AC-DC power, and for low voltage output redundant VRM DC-DC processor power. In 12V output systems, ORing circuits capable of handling currents of 100A can be made using four IRF6609 DirectFET MOSFETs in parallel. The IR5001S can also be used in reverse polarity applications for 48V/24V systems, replacing large D2Pak style diodes and an expensive relay.

When using the IR5001S with the 100V IRF6655 DirectFET® MOSFET, 30W to 60W board power levels can be addressed. The IRF6655 in the small can package offers a space reduction of about 50% versus solutions in an SO-8 package, and is more appropriate for lower power applications. The 100V IRF6644 DirectFET MOSFET in the medium can package can also be used for higher power applications, up to about 250W to 300W board power levels, eliminating the need to use multiple SO-8 devices in parallel or larger single package devices.

Oring Fet Controller

With the addition of a simple charge pump circuit, the IR5001S can also be implemented in ground ORing in -48V systems, as required by the ATCA specification (Advanced Telecom Computing Architecture).

The input terminals (INN and INP) are used to determine the output voltage by measuring the differential voltage and polarity across the drain and source terminals of the external MOSFET. The output voltage (Vout) of the IC drives the gate of the external MOSFET.

If the current reverses polarity, the IC will quickly switch the active ORing MOSFET off by pulling the Vout pin low. The turn-off delay for IR5001S is typically 130nS, with a typical 20ns FET turn-off time, which is the fastest in the industry by a factor of two, in order to minimize voltage sags on the redundant bus voltage. Usually the reverse polarity protection circuitry is mounted on the rack or panel in the system, and not on-board. Since this solution is so small, the circuit can be mounted on-board, which can significantly simplify system design.

The IR5001S IC includes diagnostic pins (FET Check 'FETch' and FET Status 'FETst') to determine the status of the active ORing circuit. This is important for systems that require the highest level of up-time. When a logic signal is sent to the FET Check pin, the output of the IR5001S (Vout), or the gate drive to the MOSFET, will pull low, turning the MOSFET off.

This momentary off period should cause the voltage across the drain-to-source terminals of the MOSFET to increase, as the current is diverted from the MOSFET channel to the body drain diode. If the voltage rises from approximately <100mV to 700mV (as expected for a body drain diode), the MOSFET is functioning normally. If the voltage does not rise above a 300mV threshold, the MOSFET is shorted. The FET status pin provides an output signal to the system, depending on the status of the external MOSFET. This feature enables system-level monitoring of the active ORing circuitry, allowing scheduled maintenance rather than the inconvenience of random system downtime.

Asymmetrical offset voltage prevents output oscillations under light load, increasing reliability. The IR5001S can be powered from either a 36V to 75V universal telecom bus voltage (100V max.) or from an external bias supply and a bias resistor for design flexibility. The IR5001S can also withstand continuous gate short conditions, and up to 100V continuous on the input pins, enabling reliable operation.

Reference design kits are available for the IR5001:

For more information related to DirectFET MOSFET Packaging Technology visit the DirectFET Home page.

Availability and Pricing

The IR5001S is available now. Pricing is US $0.67 each in 10,000-unit quantities. Prices are subject to change.