The Need for a Universal Power Adapter
As more client electronics devices shun mains power in prefer of battery operation, how we fee these devices will become an essential question. We can all take into account the huge sort of electricity adapters we had for our early mobile phones, a number of which are likely still lurking inside the again of your drawer. Alongside these chargers, we wanted power adapters for other gadgets, along with razors, cameras, and hand-held gaming consoles. Going away on business or excursion intended taking a bag of chargers with you because it was extraordinarily uncommon that you can use the charger for one tool with some other.
This began to alternate whilst USB micro-B emerged because the connector of choice for lots low-power devices, together with smartphones, smart watches, and smart home thermostats. However, because it could simplest deliver low amounts of energy—as much as about 5W—it’s far wrong for large devices.
USB-C Is Becoming Ubiquitous
Launched through the USB Implementers Forum (USB-IF) in late 2014, the USB Type-C connector popular changed into progressive in its method by means of the usage of symmetrical units of 12 interface pins, which permit the connector to be plugged in with either facet up. The new connector standard became made to be had about the same time as the USB 3.1 interface specification, although USB-C need no longer necessarily adopt the three.1 specification for communique. Furthermore, USB-C added the ability to switch different information indicators—which include the ones used for DisplayPort, HDMI, and Thunderbolt—similarly to USB statistics. The other key aspect is that USB-C gives a Power Delivery (PD) capability that is agnostic of the USB data mode. It presents two committed pins (CC1 and CC2) for negotiation with the host to supply as much as 20VDC at up to 5A.
Consequently, with its 100W power transport capability, it’s miles no surprise that USB-C is rapid becoming the frequent electricity connector of desire for a wide range of customer electronics, changing both the micro-B connector and the multitude of cylindrical ‘barrel’ connectors that have been once not unusual.
How USB Power Delivery Works
The contemporary USB-PD revision 3.Zero specification stipulates four nominal voltage degrees of 5V, 9V, 15V, and 20V with the choice to fully application the voltage in 20mV steps. In addition, the specification gives guide for output power stages as much as 100W, and the functionality to provide steady-voltage or regular-contemporary charging. This approach opens up a multitude of latest possibilities for charging devices, inclusive of laptops and other better-wattage devices, however, to gain from USB-C, the software might want to encompass a microcontroller, additional circuitry, and software program stacks.
Technical Challenges with Barrel Connector Replacement
When enforcing USB-C PD as a barrel connector replacement, the engineering crew needs to turn out to be absolutely conversant with the USB PD specification and make sure the device meets the USB-IF’s stringent certification necessities in terms of compliance and interoperability. A USB-C-compliant energy adapter is, by using nature, a programmable strength deliver that calls for conversation to permit the burden to request the preferred voltage and contemporary. As such, any layout calls for both a microcontroller and the related firmware to operate a full USB PD stack. Introducing more additives into a layout will boom the overall Bill of Materials (BOM) and require severa iterations to optimize the power circuitry and in the end create a technically and economically achievable solution.
Designing an Optimal Solution
Rather than try and enforce USB PD from scratch, engineers can use a USB-IF pre-licensed answer, together with the Cypress EZ-PD™ Barrel Connector Replacement (BCR) Evaluation Kit (CY4533). This may be used to without problems prototype a way to update a traditional barrel connector with a USB-C connector without the need to broaden any firmware. This retrofit technique offers an exceedingly short way of switching an existing product to paintings with a regular USB-C strength adapter.
Cypress’ EZ-PD Barrel Connector Replacement (BCR) Evaluation Kit embeds a Cypress CYPD3177 strength shipping controller, which designers can set to the desired load voltage and modern values by way of resistor ladder combinations with out the need to create any firmware or custom tool programming. After initial prototyping is finished, Cypress affords an smooth-to-use reference layout so that the CYPD3177, plus six resistors, may be included into the cease product together with a suitable USB-C receptacle, consisting of the Molex USB-C Connector. This connector is a part of Molex’s circle of relatives of compact USB Type-C connectors and cables, which help up to 10Gbps transfer speeds and feature full 100W energy delivery functionality. The receptacle is manufactured with a excessive-temperature nylon insert-mould housing interior a steel shell and has a middle connector plate that gives a sturdy and reliable mating action.
