How to Design a Small USB-C PD and PPS Adapter

[Introduction]For product design engineers, how to improve product competitiveness is the core challenge they face. Chargers and adapters are getting smaller; capable of providing full USB-C power delivery (PD), digitally controlled power supply (PPS) for smartphones, tablets, laptops and other portable devices; charging times are getting smaller short. We all know that the key to designing smaller chargers and adapters is to reduce component count and maximize efficiency: easier said than done.

Under the new USB protocol, it is not enough to provide a compact and efficient power conversion scheme with low power consumption. The new USB power protocol requires precise two-way communication between the powered device and the power source. USB PD enables loads and sources to set multiple power and voltage gears up to 100W (even higher powers are now being proposed). The original intention of PPS is to adapt to the continuous upgrading of battery technology, while forward-lookingly allowing the output parameters to be adjusted midway through charging. PPS supports output trimming at 20mV or 50mA.

To implement the advanced USB power protocol, in addition to the flyback controller, design engineers need to use a dedicated USB controller or microcontroller. Low-latency communication is also required between the two ICs to ensure that the entire solution conforms to the USB protocol.

solve problems

To address these challenges, design engineers can now consider a family of highly integrated flyback switcher ICs with built-in USB PD controllers. Power Integrations’ InnoSwitch™ 3-PD family of ICs is a highly integrated solution for USB Type-C, PD, and PPS adapters. In addition to the primary power switch and multi-mode quasi-resonant flyback controller, it also integrates A USB-C and PD controller (Figure 1) is included, along with primary-side detection circuitry, FluxLink™ isolated digital control, and a synchronous rectifier driver. Depending on specific parametric specifications, design engineers can choose between high-voltage silicon MOSFETs or PowiGaN™ power switches.

How to Design a Small USB-C PD and PPS Adapter

Figure 1: InnoSwitch3-PD reduces bill of materials (BOM) and simplifies the design of USB-C PD and PPS adapters

Designs based on the InnoSwitch3-PD IC comply with all global energy efficiency regulations with no-load power consumption as low as 14mW. These designs are efficient and low in losses, eliminating the need for large and costly heat sinks, helping to reduce the design form factor and cost. Power Integrations’ FluxLink high-speed communication feedback link enables fast, precise secondary-side adjustment. Input and output voltage monitoring enables accurate voltage ramp, sag, and input overvoltage protection, as well as output overvoltage and undervoltage fault detection with individually programmable fault responses. The InSOP™-24D package is very compact, measuring only 10.8mmx9.4mmx1.6mm. The InnoSwitch3-PD product family includes three ICs with internal 650V silicon MOSFETs and three ICs with internal 750V PowiGaN™ gallium nitride power switches (see Table 1).

How to Design a Small USB-C PD and PPS Adapter

Table 1: The InnoSwitch3-PD controller is suitable for various USB-C PD+PPD adapter power levels and input voltage ranges, including three ICs with internal 650V silicon MOSFETs and three internal 750V PowiGaN GaN power switches. IC

Faster time to market with off-the-shelf miniaturization solutions

To jumpstart the development of miniaturized USB-C PD+PPS adapters and chargers and speed time to market, design engineers can choose from a variety of reference designs covering 30W, 45W and 60W applications. Each of the following designs uses an IC with an internal 750V PowiGaN switch; reference designs for the silicon version of the switch are also available. They all support an input voltage range of 90 to 265VAC and meet DOE6 and CoC v5 2016 average efficiency requirements and CISPR22/EN55022 Class B conducted EMI limits.

DER-836: 30W USB PD 3.0 Power Supply

This design example (Figure 2) uses the InnoSwitch3-PD INN3878C device. The adapter measures 1.73” (44mm) x 1.73” (44mm) x 0.817” (21mm) and has a power density of 12.27W/in3 (without housing). The design has a no-load input power of <18mw at 230vac. it uses only 59 components to help improve power density. Supports the following USB PD/PPS output performance:

· PDO1: 5V/3A (fixed power supply)

· PDO2: 9V/3A (fixed power supply)

· PDO3: 12V/2.5A (fixed power supply)

· PDO4: 15V/2.0A (fixed power supply)

· PDO5: 20V/1.5A (fixed power supply)

· PDO6: 3.3V–11V/3A (digital control power supply, 30W limited power)

· PDO7: 3.3V–16V/2A (digital control power supply)‍

How to Design a Small USB-C PD and PPS Adapter

Figure 2: The reference design DER-836 uses only 59 components and delivers 30W of output power

DER-837: 45W USB PD 3.0 Power Supply

This design example (Figure 3) uses the InnoSwitch3-PD INN3879C device. It requires only 54 components, provides a power density of 14.0W/in3, and measures 1.89” (48mm) x 1.81” (46mm) x 0.94” (23.8mm) (without enclosure). It supports the following USB PD/PPS Output performance:

· PDO1: 5V/5A (fixed power supply)

· PDO2: 9V/5A (fixed power supply)

· PDO3: 15V/3A (fixed power supply)

· PDO4: 20V/2.25A (fixed power supply)

· PDO5: 3.3V–11V/5A (digital control power supply, 45W limited power)

· PDO6: 3.3V–16V/3A (digital control power supply)

· PDO7: 3.3V–21V/2.25A (digital control power supply)‍

How to Design a Small USB-C PD and PPS Adapter

Figure 3: The reference design DER-837 uses only 54 components and delivers 45W of output power

RDR-838: 60W USB PD 3.0 power supply

The reference design (Figure 4) has 61 components, measures 2.24″ (57mm) x 2.24″ (57mm) x 0.76″ (19.2mm), and has a power density of 15.7W/in3 (without case). The design uses the INN3879C Integrated controller with less USB PD/PPS output performance:

· PDO1: 5V/3A (fixed power supply)

· PDO2: 9V/3A (fixed power supply)

· PDO3: 15V/3A (fixed power supply)

· PDO4: 20V/3A (fixed power supply)

· PDO5: 3.3V–21V/3A (digital control power supply)‍

How to Design a Small USB-C PD and PPS Adapter

Figure 4: The reference design RDR-838 uses only 61 components and delivers 60W of output power

Summarize

With the innovative InnoSwitch3-PD family of highly integrated flyback switcher ICs, design engineers have a new set of tools to rapidly develop high-efficiency, very low-component-count chargers and adapters with full USB- C PD+PPS function. These full-featured ICs include a choice of both silicon or PowiGaN integrated power switch versions. They are fully protected at the input and output, enabling a solution with half the components required for traditional designs, while still delivering as low as 14mW of no-load power consumption. They are available in an ultra-thin InSOP-24D package and are suitable for mass production of high power density USB-C power solutions.

Source: Power Integrations, by Aditya Kulkarni

The Links:   QM100HY-H KT224510

Author: Yoyokuo