Jun 10 2020 5 mins 8
This week's EYE on NPI features a product I've been looking for - a USB Type C connector that is designed for power-only applications. CUI just released one, with a nice SMT/THM mixed package that's easy to solder and rework... and the price is nice! (https://www.digikey.com/en/product-highlight/c/cui-devices/power-only-usb-type-c-receptacle) (https://www.digikey.com/product-detail/en/cui-devices/UJC-HP-3-SMT-TR/2223-UJC-HP-3-SMT-CT-ND/12173367) As an ideal solution for power only applications, CUI Devices’ UJC-HP-3-SMT-TR is a 6-pin USB Type-C receptacle delivering up to 60 W of power with a 3 A current rating and 20 VDC voltage rating. Housed in a surface-mount package, this USB Type-C connector removes the data transfer pins to create a more cost-effective option for designs where power or charging is the sole function. The UJC-HP-3-SMT-TR is further compatible with standard USB Type-C plugs, taking the accessibility and simplified design integration of the widely adopted Type-C connection and applying it to power-only applications. USB Type C is a very capable & advanced interconnect system that has connector, cable, signal and software specifications. USB C is defined by a specific shape of USB connector and was designed to take that universality a step further by being the one connector for almost anything including data, power/charging, video and audio. The connector is also reversible, it has no up or down orientation! While USB C does make some things a lot easier, there is also lots of confusion and uncertainty surrounding it. There are different voltages and current limits, and a TON of pins - XKCD even made fun of the complex Type C pinout in a recent comic (https://xkcd.com/2317) For most folks who have only recently gotten a handle on the complexities of USB with 4 pins and differential signaling, the 24 pins of Type C can be a little scary. The connectors are also significantly more expensive and difficult to solder - 24 pins in a reversible case is a lot of pins! For example here is a full-pin version of the same connector style (https://www.digikey.com/product-detail/en/molex/1054500101/WM12856CT-ND/5843891) Its about $1.25 in quantity and has pins underneath the connector! Now compare that to this connector (https://www.digikey.com/product-detail/en/cui-devices/UJC-HP-3-SMT-TR/2223-UJC-HP-3-SMT-CT-ND/12173367) which is under $0.50 in quantity. That's a big BOM cost change! Of course, its less expensive because of the simpler contact structure - that trade-off means you can only use this connector for power applications, there are no USB data lines at all! The only lines that are available are VBUS, GND, and the CC1 and CC2 lines. Don't leave those CC lines floating! They are required for setting the voltage/current draw of the sink. Use two 5.1K resistors from each pin to ground to indicate a 5V. A common misunderstanding is that you can use one resistor - nope! This way the device clearly defines itself as a 5V sink. You can pick these fine connectors by the reel-full over at Digi-Key - search for part number 2223-UJC-HP-3-SMT-CT-ND (https://www.digikey.com/product-detail/en/cui-devices/UJC-HP-3-SMT-TR/2223-UJC-HP-3-SMT-CT-ND/12173367) Visit the Adafruit Shop, back open! https://www.adafruit.com/ LIVE CHAT IS HERE! http://adafru.it/discord Adafruit on Instagram: https://www.instagram.com/adafruit Subscribe to Adafruit on YouTube: http://adafru.it/subscribe New tutorials on the Adafruit Learning System: http://learn.adafruit.com/
