Power Electronic Tips

AC-DC power supplies target cardiac floating requirements

Redding Traiger — Mon, 07 Oct 2024 18:14:21 +0000

Advanced Energy has announced the NCF150 series of high-isolation, low-leakage current AC-DC power supplies that enable medical equipment designers to meet the cardiac floating (CF) requirements of the IEC 60601-1 medical safety standard using off-the-shelf products.

Type CF is the most stringent medical electrical safety classification and is essential for medical products that may come in direct contact with the heart, including dialysis machines, cardiac-related systems, and platforms for electrosurgery. With the launch of its SL Power NCF150 series of CF-rated AC-DC power supplies, Advanced Energy now offers standard, compact products that combine the performance and reliability demanded by complex medical systems with the high isolation voltage and low leakage current essential for CF certification.

Advanced Energy’s SL NCF150 series delivers maximum output power up to 150 W and offers voltages of 12 V, 15 V, 19 V, 24 V, and 48 V. An optional 5 V standby and 12 V fan output are also available. All units in the SL NCF150 series have a patient leakage current below 10 mA, feature EMI Class B, 2 MOPP isolation and 5 kV defibrillator pulse withstand capabilities.

SL NCF150 power supplies accept a universal input of 85 to 264 VAC, operate with a full-load efficiency greater than 90 percent, and feature protection against overvoltage, overload, overtemperature, and short-circuit conditions as standard. This is the first release of the CF rated family and will be followed by higher-power models launching soon.

The post AC-DC power supplies target cardiac floating requirements appeared first on Power Electronic Tips.

DC-DC series targets safety-critical applications

Aimee Kalnoskas — Wed, 25 Sep 2024 21:22:24 +0000

RECOM has introduced new DC/DC converters in the REM2A and REM4A series, designed for medical and safety-critical applications. These converters, available in through-hole and SMD formats, offer 5kVAC/1 min isolation and 2MOPP rating at 250VAC with 8mm creepage and clearance. The devices are suitable for various patient connect applications due to their low 2µA leakage current.

The converters feature 2:1 input ranges and multiple fixed, regulated DC output options. They operate across wide temperature ranges without derating at nominal inputs and can function at higher temperatures with airflow or derating. The devices include protection against various electrical issues and offer an on/off control for energy-sensitive applications.

These DC/DC converters hold certifications for medical safety and IT applications, and are specified for operation up to 5000m in pollution degree 2 environments. RECOM reports a Mean Time Between Failures of over 5 million hours at 25°C for both series. The compact packages measure 24.3 x 14.4 x 10.2mm and come with a three-year warranty.

The post DC-DC series targets safety-critical applications appeared first on Power Electronic Tips.

Transformer drivers enable compact, low-noise isolated power supplies

Redding Traiger — Thu, 19 Sep 2024 17:46:39 +0000

Nexperia introduced the NXF6501-Q100, NXF6505A-Q100, and NXF6505B-Q100. These are AEC-Q100 qualified, push-pull transformer drivers that enable the design of small, low-noise, and low-EMI isolated power supplies for a range of automotive applications like traction inverters and motor control, DC-DC converters, battery management systems and on-board chargers in electric vehicles (EV). These transformer drivers are also suitable for industrial applications like telecommunications, medical applications, instrumentation and industrial automation equipment, solar inverters, energy meters, and programmable logic controllers (PLC).

The NXF650x(A/B)-Q100 series can drive low-profile, center-tapped transformers from a 2.25 V to 5.5 V power supply with high output current (1.2 A at 5 V) and high efficiency (up to 90%). To enable small form factor designs, the devices have a 440 kHz (NXF6501 and NXF6505B) or 160 kHz (NXF6505A) internal oscillator and a gate drive circuit that produces complementary output signals to drive internal ground-referenced n-channel power switches. Alternatively, a clock signal can be applied externally to the NXF6505A and NXF6505B to enable precise control of switching harmonics or enable synchronization of multiple NFX6505x(A/B) -Q100 devices. Additionally, the NXF650x(A/B)-Q100 series employs slew rate control and spread-spectrum clocking (SSC) to deliver ultra-low noise and electromagnetic interference (EMI).

The NXF650x(A/B)-Q100 series also includes a comprehensive range of internal protection features such as over-current protection (1.7 A) with hiccup mode, under-voltage lockout, thermal shutdown, and break-before-make circuitry to ensure safe operation. Additionally, these transformer drivers have a soft-start (~5 ms) feature that prevents high inrush currents during power-up with large load capacitors. Lastly, these devices have fail-safe inputs that prevent back-powering of the local power supply and eliminate the need for power sequence management.

These devices are available in compact industry-standard footprints like the 5-pin SOT8098 (TSOT5) and 6-pin SOT8061 (TSOT6) package and safely operate in ambient temperatures ranging between -55 °C and 125 °C.

The post Transformer drivers enable compact, low-noise isolated power supplies appeared first on Power Electronic Tips.