Maschine+ Power Bank guide

ChatGPT:

Not all 65W USB-C power banks are guaranteed to deliver 15V. The voltage and power delivery (PD) specifications depend on the internal design and the power delivery profiles supported by the power bank.

USB Power Delivery (PD) specification allows for variable voltages at different power levels. Typically, USB-C PD can output a range of voltages such as 5V, 9V, 12V, 15V, and 20V, but each device (such as a power bank) may support only a subset of these voltages depending on its design.

To determine if a particular 65W USB-C power bank can deliver 15V, check:

The USB PD profiles listed in the specifications.

The power output across different voltage levels (e.g., 15V at 3A for 45W or similar).

If you need a specific voltage for a device, it's important to confirm it from the power bank’s specs. Some may deliver 65W using only 20V at higher amperages, for example.

ME:

Are you sure? Isnt USB-C supposed to negotiate the power requirements? Why would it be able to deliver 20V but not 15V which is lower?

ChatGPT:

You're absolutely right that USB-C Power Delivery (PD) is designed to negotiate power dynamically between the charger and the device. However, not all USB-C power banks support every available voltage profile in the USB-PD specification.

Here's why a power bank might support 20V but not 15V:

USB-PD Profiles:

USB-C PD negotiates voltage and current levels based on the capabilities of the power bank and the needs of the connected device. The PD standard allows for a range of fixed voltage profiles: 5V, 9V, 12V, 15V, and 20V. However, just because USB-PD supports these voltage levels doesn't mean that every device implements all of them.

Manufacturer Choices:

Some manufacturers design power banks to optimize for specific use cases. For example:

A power bank designed for high-power laptops may prioritize 20V (for 65W output) and may not include support for 15V because the higher voltage is needed to maximize efficiency at higher power levels.

A power bank might support 5V, 9V, and 20V for a range of devices (phones, tablets, laptops), but omit 15V if they don't see a common need for that profile in the market.

Power Efficiency:

Higher voltages like 20V can allow for more efficient charging for high-wattage devices. If a power bank is primarily marketed for laptops, it may focus on the 20V profile because many laptops prefer 20V to charge faster and more efficiently.

Summary:

While USB-PD is flexible, each power bank implements specific voltage levels that match the intended use case and cost considerations. So, even though delivering 15V would seem natural (as it is lower than 20V), it still requires the power bank to have the necessary circuitry to support it. Always check the specs for the exact PD profiles offered by a power bank to ensure it supports the voltage you need, such as 15V.