700-V buck regulators minimize EMI, eliminate audible noise

Renesas Electronics Corp. has introduced a new family of 700-V buck regulators that offers low power consumption, no audible noise, and reduced electromagnetic interference (EMI). The RAA2230XX devices target a range of applications, including home appliances, sensing systems such as smoke alarms and gas sensors, white goods, power meters and industrial controls.

The RAA2230XX buck regulators consume only 10 mW to 30 mW when idle to help meet standby power regulations. They feature a unique switching algorithm that minimizes EMI and eliminates audible noise, such as ‘humming’ or ‘whining.’

The regulators can supply as low as 3.3-V output, which can eliminate a second-stage low dropout regulator (LDO) to save cost and board space, said Renesas.

 The buck regulators connect to the AC line to power Renesas MCUs, sensors, and other digital ICs. They support both non-isolated buck and isolated flyback topologies, which allows designers to develop multiple types of AC input power supplies.

The 700-V RAA2230XX buck regulators are available in TSOT23-5, SOIC-8 and SOIC-7 package options. The family includes 2-W, 4-W and 8-W versions. Evaluations boards for different package and output combinations also are available.

Renesas RAA223012 block diagram (Source: Renesas Electronics)

As part of Renesas’s Winning Combinations portfolio, the company offers, as an example, the Household Smoke Detector winning combination using the RAA223012 regulator, which demonstrates a turnkey architecture for a residential smoke alarm, suitable for smart industrial control terminals.