Expanding its portfolio of high-voltage power solutions for offline AC/DC designs, Texas Instruments (TI) has introduced a 700-V switcher with the industry’s lowest quiescent current of less than 100 uA – half the power consumption of existing solutions. The UCC28880 controller integrates a 700-V power MOSFET and high-voltage current source, increasing overall energy efficiency of “always-on” non-isolated power systems with output currents up to 100 mA, such as smart meters, home automation equipment and white goods. 

“Hundreds of millions of smart meters around the world continuously draw power from the grid to measure energy use and provide feedback to the utility,” said Dave Freeman, chief technology officer for TI’s high-voltage power solutions group. “Even though meters consume relatively small amounts of power that is not charged to the customer, when you multiply the amount of energy needed to power the devices, it makes sense to minimise the energy consumed. New power conversion technologies, such as TI’s new high-voltage power solution will help smart meters minimise energy consumption.”

The UCC28880 high-voltage switcher reduces system cost and minimizes the overall size of the power supply, while maintaining high efficiency and system performance. Designers can use the switcher to build different converter topologies, such as buck, buck-boost and flyback, without adding extra semiconductor components.

Key features and benefits of the UCC28880

·         Industry’s lowest power consumption: As the load is reduced, the quiescent current is reduced to below 100-uA.

·         Reduces application size and overall system cost: The circuit integrates a 700-V MOSFET, start-up current source and internal current sensing in a tiny 7-pin SO package size of 29.4mm2. Additionally, no external compensation is needed which further reduces component count and board space.

·         Excellent system performance under excessive currents: Along with current limit function, the controller’s inductor current runaway protection helps protect against under load short-circuit conditions to ensure design reliability.

·         Thermal protection: The device provides over-temperature protection with hysteretic re-start for safe operation.

·         Increased creepage and clearance: High-voltage pins are segregated to one side of the package, which maximises separation between low and high voltage pins.

An offline, AC/DC reference design based on the UCC28880 (PMP8550) enables designers to quickly design a low-cost, low-power non-isolated high-side buck converter with a total solution size of 38mm by 32mm by 22mm that supports 13 V, while generating up to 100 mA of output current. The reference design features a buck converter with integrated switch and can be used in numerous industrial applications. The design’s schematic, CAD files and test results are available for download.

Availability and pricing

The UCC28880 switcher with integrated 700-V FET is available now in a 7-pin SOIC package and priced at US$0.55 in 1,000-unit quantities. The UCC28880 low-side buck evaluation module (EVM) and high-side buck EVM are priced at $49 and include a downloadable PSpice model.