Silanna Semiconductor Debuts CO2 Smart Power Family of High Efficiency 100W DC-DC Converters
The tiny buck converters, aimed at USB-PD applications, operate over 7 to 27 VDC inputs and supply 3.3 to 21 VDC
Silanna’s SZDL3105B and SZDL3105A are part of Silanna’s CO2 Smart Power family of wide-voltage, high-frequency point of load (POL) converters. They are offered in 4 x 4mm QFN packages and operate at a switching speed of 667kHz, enabling them to offer best-in-class efficiency, power density and substantial BoM savings.
USB port application diagram for the SZDL3105B. Image courtesy of Silanna
The Value Proposition for the SZDL3105
As explained by Tim Wilhelm, Director of Marketing, “Higher switching frequency means a smaller, lower cost, higher-performing output filter that has delighted the clients we have sampled. The SZDPL3105B device enables ground-breaking efficiencies in the smallest size and weight designs.
Applications based on the SZDL3105 take up far less volume than designs based on lower-frequency solutions. Image courtesy of Silanna
He goes on to state that, “Our support tools give customers the flexibility and confidence to quickly increase the performance efficiency. This ultimately increases power density with volumes approaching 12% of that required by low-frequency competitive solutions. The SZDL3105 significantly reduces BOM cost, design cycles and time to market.”
Designed for a Smooth Power-up
On start-up, the SZDL3105B utilizes an internal feedback pathway to allow for a smooth startup. Once the external USB port controller can power up to take control of the output voltage, the SZDL3105B disconnects the internal FB divider. The SZDL3105A relies on an external resistor divider to provide feedback for output voltage regulation.
Power Efficiency and No Load Current Drain
The SZDL3105 features exceptionally low power dissipation, enabling very low no-load power. Because of the worldwide push to conserve energy, low no-load power is a key criteria necessary for regulatory certification.
“As far as chargers go, I want to give kudos to some OEMs out there. They are driving no-load power or vampire power down to new levels. We have very good no-load power performance. But we also have ways to make it even better,” Wilhelm said in an interview with EE Power.
Observation of the graphs contained in the datasheet reveals that the device consumes about 0.1 watts during no-load conditions. At 100 watts output (20 VDC at 5 amps, efficiency is at just under 99%
Features and Protections that Designers Expect
The SZDL3105 offers:
- Overcurrent protection (OCP)
- Overvoltage protection (OVP)
- Overtemperature protection (OTP)
Undervoltage lockout (UVLO ) is programmable
- USB-PD 3.0 and PPS applications are both covered by the units’ 5 amp, 3.3V to 21V output
- VBUS Supply Generation for USB-PD Ports:
- Multiple Output USB-PD Chargers
- Displays and Televisions
- Laptop Docking Stations
- Charging Hubs
- High Voltage POL Supplies
Getting to Market Faster
Silanna offers Evaluation Boards, a full range of Reference Designs and a Design Tool Application
The valuation boards allow for a complete assessment of the SZDL3105’s DC/DC performance. There are also daughter boards to evaluate the converters’ performance with Power Delivery (PD) and Fast Charge Port controllers, both Type-C and Type-A
Silanna makes available full reference designs for chargers. The complete charger designs include the case, as well as full test reports
Power Density Hero is a complete all-in-one design tool. The interactive application allows users to enter environmental variables and preferences for specific components. It supplies a full schematic along with a complete BOM.