Alpha and Omega Semiconductor Introduces a New AC-DC Active Bridge Rectifier Solution

­Alpha and Omega Semiconductor Limited (AOS) introduced an extension to its active bridge driver, AlphaZBL™ family. Available in an SOP-8L package, the AOZ7203AV is a self-powered dual driver IC for driving external high-voltage MOSFETs to replace twolow-side diodes of bridge rectifier. The new device is suitable for use in adapters for high-end laptops and televisions, as well as power supplies for Desktops, Game consoles, and Servers.

The new AOZ7203AV features a high withstand voltage, a self-powered Vcc supply from the AC line, ultra-low operation current, and X-capacitor discharge (CB safety certified). A break-before-make circuit avoids the overlap oftwo gate driving while driving the low-side high voltage MOSFETs in an active bridge rectifier circuit. With an input voltage of up to 600V,the AOZ7203AV has a wide operating (-40°C to +125°C) ambient temperature range and driving low RDSONHV MOSFETs to gain more efficiency improvement of AC power supply. These features make the AOZ7203AVan optimal solution for efficient replacement of lossy diodes in the bridge rectifier circuit of an AC-DC power supply.

“Today’s power-hungry gaming laptops, game consoles, and high-performance desktops demand high efficiency from the AC-DC power supply. Using the AOZ7203AV with AOS’ low-ohmic high-voltage external MOSFETs significantly improves the efficiency of the power converter as the typical rectifier-diode forward-conduction losses are reduced by 50 %. Efficiency can improve up to about 0.7 % at 90 V mains voltage.” said Armin Hsu, Power IC Senior Marketing Manager at AOS.

Technical Highlights

• The AOZ7203AV combined with two High Voltage MOSFETs replaces two low-side diodes in a bridge rectifier
• Increases efficiency and reduces power consumption
• Self-powered from AC mains
• Integrated X-capacitor discharge
• Low IC power consumption
• Two drivers in one package enable a more compact design
• Break-before-make circuit avoids overlapping gate drive signal to HV MOSFETs
• Very low external part counts
• Undervoltage lockout
• Drain-source overvoltage protection for all external power MOSFETs
• Gate pull-down currents at startup for all external power MOSFETs

Pricing and Availability

The AOZ7203AV is immediately available in production quantities with a lead time of 14 weeks. The unit price in 1,000-piece quantities is $1.68 USD. AOS products are offered in packages with Pb-free plating and are RoHS compliant.

For more information, please go here.