USB Typet-C Orientation Detection for Power Delivery

[AJollet]

Hey everyone,
I'm basically trying to make a USB rechargeable device that will be charged through a Type-C connector (purely for ease of use) and possibly by a Type-C hub on the host side.
From what I gathered so far, the power lines are purely symmetrical on the connector so they're not a problem.
I also read that the CC pins are used for cable orientation detection to allow proper routing of the different differential signals.
I for battery charging purposes I don't really care about that but I was wondering if a Type-C hub needed to detect cable orientation in order to supply power to the device.

To put it in more simple words, can I just leave all pins but the power pins floating on the device side and expect any power to be delivered ?

[Dave]

It depends on the host, but as far as I'm aware, you need the device to be enumerated to get the host to provide power. You're going to need some sort of chip that tells the host: "Hey, I need this much power, feed me!"

[HKJ]

To put it in more simple words, can I just leave all pins but the power pins floating on the device side and expect any power to be delivered ?

No, you need a resistor to say you are a downstream device.
Technically this gives you access to lowest power level and by checking the voltage at the resistor you can see if you can draw more power.
You can also look for the usual usb data bus codes.

[lucazader]

Yea all you need is a pull down resistor on on of the two CC lines.

For default usb power (5v 500/900ma) it is a 5.1k pulldown resistor.
I am not sure what the values for the following are, but they are also available power options, using resistors.
5V 1.5A
5V 3A

In testing I have found that most USB wall chargers dont need the resistors to provide power, howver most properly implemented ports do need one of these resistors to start providing power.

For any power levels over 5v or over 3A, you would need to get a Power Delivery chip than can communicate with the power provider to negotiate the higher power levels.

[HKJ]

For default usb power (5v 500/900ma) it is a 5.1k pulldown resistor.
I am not sure what the values for the following are, but they are also available power options, using resistors.
5V 1.5A
5V 3A

It is the power supply that need different resistor, depending on the power level. You check the voltage across the pulldown resistor to see what resistor is in the power supply.

For any power levels over 5v or over 3A, you would need to get a Power Delivery chip than can communicate with the power provider to negotiate the higher power levels.

Not always, today you will often find QuickCharge (or other usb protocol) on usb-c chargers or usb charger with conversion cable.