Product roundup: AC/DC power supplies

The demand for AC/DC power supplies is constantly growing in medical and industrial equipment. In many cases, the requirements for these power supplies overlap, allowing them to be used in both applications.

Regardless of their final application, AC/DC power supplies today must meet increasingly stringent requirements, which include:

• Small size: Miniaturization is now a common trend in most electronic applications. A small form factor allows for more compact solutions, thus reducing the overall weight and the space occupied.
• High power density: Higher power density, now possible thanks to the availability of wide-bandgap semiconductors like silicon carbide and gallium nitride, enables the power levels required by the latest applications using fewer and smaller power modules.
• High efficiency: The need to reduce CO₂ emissions to combat global warming requires solutions that maximize efficiency while minimizing power and heat losses.

Other requirements, specific to individual applications, include the capability to operate without cooling fans, low emission of electromagnetic radiation and the configurability or programmability of the device, even remotely. Here is a review of some recently introduced AC/DC power supplies, including modules, for medical and/or industrial applications.

Cincon PFC750

Although the concept of energy savings is widespread in today’s sectors, nearly all power supply manufacturers anticipate a breakthrough in delivering lower power consumption with high efficiency. This is the case of the PFC750 modules from Cincon Electronics Co. Ltd., which has been designed with an integrated active power-factor correction (PFC), while boasting a low profile, small footprint and high efficiency.

Energy Star guidelines recommend that consumer devices with a power consumption above 100 W achieve at least a 0.9 power factor (PF) to increase energy efficiency. High PF results in less power wasted in running devices. Cincon’s new PFC750 module achieves a PF of 0.99 by using an active PFC, which employs a boost converter to enhance the switching frequency and to control the shape of the waveform in the input current. Active PFC adjusts the PF value more efficiently and directly than a passive PFC.

The PFC750 module, which comes as an industry-standard half-brick and low-profile AC/DC power converter, achieves up to 96.5% efficiency, providing 750-W output power at 390-VDC output voltage. With a universal input range of 90–264 VAC, the device can operate over a temperature range of –40˚C to 100˚C and features an extended lifetime because it does not include an electrolytic capacitor.

The typical application circuit is shown in Figure 1. The external EMI filter is recommended to reduce the electrical noise and the external capacitors, C1 and C2, are required to stabilize the output voltage, while TRF1 is used to limit the input inrush current.

XP Power FCB100

XP Power has launched the FCB100 series of 100-W AC/DC power supplies for industrial, information technology equipment and medical devices, including body floating (BF).

All versions in the FCB100 series (Figure 2) feature a no-load power consumption of less than 0.3 W and accept a wide operational input voltage range of 80–264 VAC, supporting global compatibility and home health-care applications with six standard output voltages: 12 V, 15 V, 19 V, 24 V, 36 V and 48 VDC.

The FCB100 series operates at temperatures between –25˚C and 70˚C, providing 100 W at up to 50˚C with external forced air conditioning and derating linearly to 50 W at 70˚C. Depending on the type, the units can be convection-cooled for minimal audible noise, providing 80/85 W at up to 50˚C before linearly derating to 40/45 W at 70˚C. The open-frame variants weigh 160 grams and measure 101.6 × 50.8 × 31.8 mm (4 × 2 × 1.25 inches). The devices also come standard with overvoltage, overload, short-circuit and overtemperature protection.

With an input-to-output isolation of 4,000 VAC (2 × MOPP), all devices are suitable for use in BF-rated medical devices.

Powerbox OFI700A

Powerbox’s OFI700A is a 700-W power supply suitable for industrial applications. The AC/DC power supply, which is designed for conduction cooling, provides outstanding performance levels without requiring a fan over a baseplate temperature range of –40˚C to 95˚C. The power supply is available with DC outputs of 12 V/58.4 A, 28 V/25 A (adjustable to 24 V) or 48 V/14.6 A and operates with a broad universal input range of 85–264 VAC with PFC. The output voltage can be adjusted using the provided on-board potentiometer. An additional voltage of 12 V/0.1 A is also available for auxiliary functions.

Conduction cooling is required in harsh industrial environments where active ventilation, such as fans and blowers, is not possible or even allowed. The OFI700A (Figure 3) includes a PFC with a coefficient of 0.95/0.92 (110 VAC/230 VAC). It is also possible to connect two units in parallel for applications requiring 1 + 1 redundancy, adding an external diode to protect the unit.

The OFI700A provides an IN/OUT isolation of 3,000 VAC and an IN/FG isolation of 2,000 VAC for safety purposes. A 500-VAC output isolation to FG is used. The power supply provides overvoltage, overcurrent and overtemperature protection with auto recovery.

Recom RACM90-K

Recom Power GmbH has recently released the 90-W versions of the versatile and cost-efficient RACM 2 × 4-inch AC/DC series. Providing a wide 85- to 264-VAC input range and a range of regulated outputs, including 12 V, 15 V, 24 V, 36 V and 48 VDC, the series is compliant to medical standard IEC/EN/ANSI/AAMI ES 60601-1 for 2 × MOPP B and BF applications, as well as IEC/EN 62368-1, IEC/EN 60335-1 and IEC/EN 61558-1 for reinforced isolation in industrial, IT, test and measurement and household use, all to a 4,000-meter altitude.

The devices are designated as limited power source (LPS) and can be used in installations with surges of Class 3 and overvoltages of Category OVC III. The efficiency is high, typically up to 90% depending on the version, and the EN 55032/35 Class B emission limitations are satisfied with a good margin. This value is maintained down to light loads to enable compliance with ErP standards. At 230 VAC, no-load loss is less than 200 mW.

The parts are offered in 2 × 4-inch industry-standard open-card units (Figure 4) and with an optional metallic enclosure. The operating temperature ranges from –40˚C to 90˚C with derating.

Cosel AEA1000F

Cosel Co., Ltd. has introduced the AEA1000F series, 1,000-W free-air convection-cooling AC/DC power supplies suitable for challenging industrial applications, medical equipment and BF applications.

Able to deliver 330% peak power for a period of up to 3,000 ms, the new devices have been designed to meet the requirements of high-safety applications. The AEA1000F is certified according to the EN 62477-1 (OVC III) standard for industrial applications and is approved in accordance with ANSI/AAMI ES 60601-1 and EN 60601-1 3rd Edition for medical applications.

Featuring a layout optimized for free-air convection, the new product provides input-to-output isolation compliant to 2 × MOPP (IN/OUT) and 1 × MOPP (OUT/FG) safety requirement, making it suited for operating in low-noise environments.

Additionally, the AEA1000F offers a 4,000-VAC input-to-output isolation, a 2,000-VAC input-to-ground isolation and a 1,500-VAC output-to-ground isolation. The input voltage ranges from 85 to 264 VAC with three available output voltages: 24 V/42 A, 36 V/28 A and 48 V/21 A. A built-in potentiometer can be used to adjust the output voltage.

The AEA1000F (Figure 5) features an active PFC for low harmonic current distortion, while the switching stage uses an LLC resonant architecture, giving a typical efficiency of up to 95%. Up to six AEA1000F units can be connected in parallel for more power.

TDK-Lambda CUS600M

The CUS600M from TDK-Lambda is a new series of compact AC/DC power supplies with 12-V, 19-V, 24-V, 28-V, 32-V, 36-V and 48-V single-output voltages, which can deliver 600 W with forced-air cooling, or 400 W with 600-W peak power when convection-cooled.

Available in an industry-standard 3 × 5-inch package, the CUS600M (Figure 6) has medical and ITE certifications and is suitable for both Class I and Class II (no earth wire) applications, offering efficiencies of up to 96%, no-load power consumption of less than 0.5 W and a 5-V/2-A standby voltage.

Additional features include remote on/off, remote sense and a power-good signal. Typical applications include medical (B and BF type), home health care, dental, test and measurement, broadcast, professional audio and industrial equipment.

Vox Power VCCM600M

The conduction-cooled customizable power supply series from Vox Power Ltd., the VCCM600, combines the benefits of a modular power supply with the high reliability of a fan-less design. In a rugged 4 × 7 × 1.61-inch package, the device delivers 600 W and up to 750 W of peak power for five seconds. The VCCM600 is the best power option for demanding industrial and medical applications in which audible noise and reliability are issues.

Depending on the application, the VCCM600 series (Figure 7) can be configured as a forced-air, convection- or conduction-cooled system, enabling it to be used in a variety of settings, including harsh industrial applications and places with strict environmental controls. Each configured solution may support up to four isolated DC output modules, each delivering from 1.5 to 58 VDC at 150 W per channel. Other features include a 5-V/1-A bias supply and a five-year guarantee.

The series offers market-leading specifications and design-in application support. It is certified to the most recent medical safety (IEC/UL 60601-1 3rd Edition) and electromagnetic compatibility (EMC) standards. The VCCM600M has received medical approval, provides standby power of less than 1 W (in primary inhibit mode) and features efficiency up to 92%.

CUI VMS-130

The VMS-130 series from CUI Inc. is comprised of open-frame and IEC 60601-1–approved AC/DC power supplies designed for a variety of medical and dental products. These power supplies are suited for medical designs looking to reduce standby and total power usage, thanks to their industry-standard 2 × 3-inch footprint, PFC and efficiency up to 94%.

Offering a 130-W output power with forced-air cooling (100 W with natural convection), these power supplies (Figure 8) provide 12- to 48-VDC output voltage options and an 80- to 264-VAC input voltage range, and they are available with an open-frame, baseplate or covered design.

TT Electronics TAAM700

TT Electronics’ TAAM700 is a 700-W medical-grade enclosed power supply that, in a reduced 6.7 × 3.66-inch footprint, provides a power density of 17.8 W/in.³ and a wide operating temperature range of –30˚C to 70˚C. The TAAM700 power supply’s high power density makes it suited for space-constrained health-care and industrial equipment, such as laser devices and robotics, where good thermal management is needed.

This cost-effective and efficient (up to 92%) power supply offers BF-rated outputs, an optional built-in current share that can be configured to 1.26 kW, a remote ON/OFF function and 625–700 W of continuous output power. The TAAM700 meets UL/EN/IEC 60601-1 approval and each model complies with several standards, including UL, IEC, CE, UKCA and the FCC PART 15 and EN 55032 Class B emission limitations.

With standard output voltages between 12 VDC and 48 VDC, the TAAM700 (Figure 9) is suitable for space-constrained applications and where high efficiency and safety/EMC compliance are critical.