Develop high-efficiency, high-power-density charging solutions with a low Bom

Silanna’s new RD-5 reference design combines our CO2 Smart Power (TM) families of advanced ACF controllers and high-frequency DC/DC converters to provide a production-ready solution for multi-port 65W USB-PD applications.

AnyPort will simplify and speed charger development by providing everything an engineer needs to rapidly prototype and test a fully functional 65W 2C unit.

The design, which combines Silanna’s SZ1130 fully-integrated AC/DC active clamp flyback (ACF) controller and two of the company’s SZPL3102 DC/DC converters, provides a cased power density of 11.4W/inch3 and operates with an end-to-end peak efficiency in excess of 91.5%.

The SZ1130/1131

Silanna’s ultra-high-efficiency SZ1130 and SZ1131 ACF controllers are now in full production and rated for powers up to 65W in universal input designs and above 100W in PFC applications.

The controller integrates into an ultra-compact 16-pin SOIC package an adaptive digital PWM controller, ultra-high-voltage (UHV) active clamp FET, active clamp gate driver and startup regulator and provides the simplicity of a simple flyback controller with all the benefits of an ACF design.

This includes recycling the leakage inductance energy of the flyback transformer and limiting the primary FET drain voltage spike during turn-off events. Employing Silanna Semiconductor’s OptiModeTM digital control architecture, the SZ1130 adjusts the device’s mode of operation on a cycle-by-cycle basis to maintain high efficiency, low EMI, fast dynamic load regulation, and other key power supply parameters in response to varying line voltage and load conditions.

The SZPL3102

Supplied in a tiny 3mm x 3mm QFN package, the SZPL3102 is a high-voltage, high-efficiency 65W integrated buck converter with a selectable switching frequency up to 2MHz.

The device offers a wide input range of 7V to 27V, delivers a maximum output current of 3.25A and has unique features to optimize performance in USB port power supply applications.

Extremely low operating power dissipation enables very low no-load power – an important specification for regulatory certification – while a momentary internal feedback path allows for clean and well controlled start-up operation until external USB-PD controllers can bias themselves and take over control of the output voltage. 

RD-5 Key Features

  • 65W 2C high-power-density AnyPort™ reference design
  • 4 W/inch3 cased power density
  • > 91.5% peak end-to-end efficiency
  • > 6dB conducted and radiated EMI margins 
  • Flat efficiency across universal (90 – 265Vac) input voltage and load 
  • Uses Silanna Semiconductor’s fully integrated ACF controller (SZ1130)
    • SZ1130 integrates ACF controller with UHV active clamp FET, active clamp driver, and start-up regulator
    • Up to 146kHz switching frequency operation
    • OptiMode™ cycle-by-cycle adaptive digital control
    • Self-tuning valley mode switching (VMS)
    • Multi-mode operation (burst mode, QR, VMS)
    • OTP, OVP, OCP, OPP, and Output Short Circuit Protections
    • Space-saving 16-pin SOIC package
  • Uses Silanna Semiconductor’s high-voltage, high-efficiency 65W integrated buck converter (SZPL3102)
    • Selectable switching frequency up to 2MHz
    • Optimal high efficiencies for 3.3V to 21V VOUT
    • Maximum output current of 3.25A
    • Wide input voltage range: 7V to 27V
    • Selectable soft start times
    • OCP/OVP/OTP protection
    • Programmable UVLO
    • 3mm x 3mm QFN package