Renesas have unveiled a family of 700V buck regulators that offers designers numerous advantages over competitive solutions. The RAA2230XX family deliver superior power consumption, noise and EMI suppression, as well as reduced overall system cost.
The RAA2230XX family are universal input AC/DC switching buck regulators that feature a 700V integrated MOSFET capable of delivering up to 8W output power depending on model selected, with the output voltage as low as 3.3V and various package options. The converters feature a unique constant-off-time control method that helps to achieve ultra-low standby power, negligible EMI, and no audible noise. The product family also supports secondary-side-feedback isolated flyback topology. The family combines constant off-time control for heavy load and Pulse Frequency Modulation (PFM) for light-load operation. Constant off-time controls switching frequency above the audible frequency of approximately 50kHz (30kHz for RAA223011). PFM eliminates any potential audible noises while offering superior light-load efficiency and ultra-low power consumption < 10mW at no load (< 20mW at no load for RAA223021). Efficiency is achieved up to 80% (75% for RAA223012). The built-in frequency dithering further reduces the EMI noise spectrum.
The RAA2230XX buck regulators consume only 10mW to 20mW when idle, helping system designers meet ever-tightening standby power regulations. They feature a unique switching algorithm which minimizes electromagnetic interference (EMI) and eliminates audible noise, such as ‘humming’ or ‘whining’ that can affect competitors’ solutions. The new regulators can also supply as low as 3.3V output, enabling designers to eliminate a second-stage low dropout regulator (LDO), saving BOM cost and board space. Furthermore the regulators have been designed to be pin-to- pin compatible with other industry competitors devices, this allows designers to take advantage of the advanced features in the RAA2230XX family on existing designs without an expensive and time consuming redesign of the PCB.
Most domestic appliances, power adapters, and sensor devices such as smoke alarms are powered by AC wall sockets. Because these loads require a constant DC voltage to function, AC/DC conversion between the AC source and the loads is required. This conversion can be accomplished with a non-isolated buck-converter, as shown in below schematic, or through isolated topologies like flyback converters.
Basic AC/DC conversion topology (buck)
There are some critical common challenges encountered during the development of the AC/DC converter:
Renesas have addressed these challenges with the RAA223011, RAA223012 and RAA223021 700V buck regulators, the schematic for the non-isolated buck configuration is shown in below schematic and the devices also support isolated flyback topologies.
RAA2230xx 700V regulator family schematic
The converters are available in a range of package options, TSOT23-5, SOIC-8 and SOIC-7, and have an operating temperature range from -40 to +125°C.
The RAA2230XX family is ideal for a wide range of applications, including home appliances, sensing systems such as smoke alarms and gas sensors, white goods, power meters and industrial controls.
Design Support
The RAA2230XX family is supported by a range of evaluation boards which allow developers to explore the full features of the high voltage flyback converters, the boards demonstrate low-cost high performance isolated or non-isolated AC/DC conversion from a universal input of 85VAC to 265VAC, to a low voltage DC output with various output currents up to 1A. The evaluation boards feature built-in overcurrent, short-circuit, input brownout and over-temperature protections, and are designed on a double side Printed Circuit Board (PCB) with a full-wave input rectification. Some of the boards are also pre-compliant with the conducted EMI requirements by EN55022/CISPR 22 allowing use as a reference design saving valuable development time and cost.
Winning Combinations
The RAA2230XX buck regulators can be connected to the AC line allowing them to power MCUs, sensors and other digital ICs within the system. Renesas has developed numerous Winning Combinations that include the new devices. Winning Combinations consist of complementary analog, power, timing devices and embedded processing, and provide an easy-to-use architecture, simplifying the design process and significantly reducing design risk for customers in a wide variety of applications. For example, the Household Smoke Detector winning combination demonstrates a turnkey architecture for a residential smoke alarm, suitable for smart industrial control terminals. For this and additional Renesas solutions, go to www.renesas.com/win. Renesas offers over 200 winning combinations with compatible devices that work together seamlessly.
Anglia are offering customers a FREE evaluation board and samples of the RAA2230XX family of high voltage buck converters from Renesas, please fill in the form below to register for evaluation kit and samples now.
Free samples are subject to availability.
STMicroelectronics has unveiled the ST1VAFE3BX, the first dual-function biosensor combining a vertical analog front-end (vAFE) for detecting biopotential signals and a 3-axis ultralow-power accelerometer for motion tracking.
Panasonic have one of the widest ranges of Polymer capacitors available in the industry. Polymer capacitors have excellent frequency characteristics due to their ultra-low ESR (Equivalent Series Resistance) values; they exhibit low impedance near their resonance point which reduces AC ripple in power circuits.
The SignalBee family of Wire-to-Wire and Wire-to-Board connectors from HIROSE offers a plethora of solutions for signal cable connections, featuring compact size combined with high-end performance.
The G5Q series from OMRON offers a compact, slimline and versatile relay suitable for a wide variety of applications, the G5Q has become a global standard for compact power relays having sold more than 500 million units since its launch in 2001. OMRON have now expanded the series with the latest addition of the G5Q-HR(TV8) for high inrush loads to TV-8 specification.
Bourns Inc., a leading manufacturer and supplier of electronic components for power, protection, and sensing solutions, has announced the release of the Model SSD Shunt Sensor - Digital Series. These Digital DC Current Sensors offer superior accuracy, stability and electrical isolation and provide high accuracy over a wide operating temperature range.
The STM32N6x7 family is STMicroelectronics newest and most powerful STM32 MCU to date and the first to come with their Neural-ART Accelerator.
Sensirion have released the SENSEVAL-SCB4XV1 evaluation board which combines temperature, humidity, indoor air quality and barometric pressure sensor in one board. This evaluation board features a unique combination of the Sensirion SHT40 humidity and temperature sensor, SGP40 indoor air quality VOC sensor and a STMicroelectronics LPS22DF barometric pressure sensor and is compatible with the STMicroelectronics DIL 24 socket system.