Design Win

45W USB Type-C Power Delivery adapter

Solution Description

For USB Type-C Power Delivery adapters, optimum coherence between the QR mode flyback controller, synchronous rectification controller, and USB Type-C Power Delivery controller is critical to system performance. St has done the heavy lifting to provide a robust solution to design adapters to maximize power output for the smallest form-factor with lowest bill of material.


The EVLSTCH03-45WPD USB Type-C Power Delivery 3.0 adapter is a USB-IF certified solution and reference design. This evaluation board helps designers to quickly develop adapters with a short bill of materials in order to obtain a cost-effective and fast design that meets all DoE and UE CoC requirements.

Beyond the main silicon controllers, St also provides the main power devices and ESD protection needed for a complete hardware solution in a compact, cost-optimized design.

The EVLSTCH03-45WPD 45W USB Type-C® Power Delivery 3.0 adapter is a USB-IF certified solution and reference design.

The EVLSTCH03-45WPD is an isolated power supply with a standalone USB PD controller. The evaluation board implements at the primary side a quasi-resonant flyback converter based on the STCH03 controller with optocoupler feedback for voltage regulation. This controller combines a high performance low-voltage PWM controller chip with a 650 V HV start-up cell in the same package. The STCH03 controller drives the gate of the new 650 V MDmesh™ M6 technology Power MOSFET STD7N65M6.

At the secondary side, to increase the system efficiency, the rectification is based on the SRK1001 adaptive synchronous rectification controller. This controller drives the gate of the 100V STripFET™ F7 technology Power MOSFET STL110N10F7.

Always on the secondary side the CC/CV regulation loop to drive the power regulation stage and the USB Type-C® PD interface are based on the STUSB4761 controller. This controller offers the benefits of a full hardware USB PD stack allowing robust, deterministic and safe negotiation in line with USB PD standard.

The EVLSTCH03-45WPD is protected against destructive electrostatic discharge from the USB Type-C® connector using a Dual Transil array for ESD protection ESDA25L.

The evaluation board implements a robust adapter protected for output overvoltage, output undervoltage, output overpower and output short-circuit. This reference design, based on STMicroelectronics semiconductors, helps designers to develop adapters with a short bill of materials in order to obtain a cost-effective and fast design.

  • Key Product Benefits

    STCH03 - Offline PWM controller for low standby adapters

    The STCH03 is a quasi-resonant flyback controller with HV start-up cell and a high performance low voltage PWM controller chip in the same package that minimizes power consumption. This PWM controller turns on the primary MOSFET to allow energy to be stored inside the primary winding of the flyback transformer during the ON time. After the primary MOSFET turn-off, the energy is electromagnetically transferred to the secondary winding of the flyback transformer and hence to the secondary side capacitors and load.

    SRK1001 - Adaptive synchronous rectification controller for flyback converter

    The SRK1001 controller is designed for secondary side synchronous rectification (SR) in flyback converters, suitable for operation in QR and mixed CCM/DCM fixed frequency circuits.

    STUSB4761 -Standalone USB PD controller with integrated CC/CV for AC/DC applications

    The STUSB4761 addresses USB type-C and Power Delivery provider devices. Thanks to default parameters stored in an internal non-volatile-memory, the STUSB4761 implements up to 5 PDOs in order to negotiate autonomously a Power Delivery contract with a sink without any internal or external software (auto run mode). A CC/CV regulation loop allows a fully regulated power management unit (AC/DC) to be implemented with a minimum BOM cost. Automatic overheating protection mechanism allows to renegotiate power down with the SINK in order to contain and decrease abnormal temperature elevation, protecting the application, the charging device and the environment.

  • All Features

    • USB-IF certified
    • USB Type-C PD 3.0 references:
      • Power Brick EVLSTCH03-45WPD TID: 2071
    • PD Controller STUSB4761 TID: 2070
    • Energy efficiency meeting all DOE and UE CoC requirements
    • Isolated quasi-resonant flyback topology with adaptive synchronous rectification
    • Programmable output voltage and current protections
    • Safety according to EN60065
    • EMI according to EN55022 - Class B
    • RoHS compliant