When choosing a docking station or USB hub, it's important to understand the difference between Power Delivery (PD) and Pass-Through Power Delivery. While both terms refer to charging capabilities, they function differently and impact how power is distributed to connected devices.
What is Power Delivery (PD)?
USB Power Delivery (PD) is a fast-charging standard that allows devices to negotiate power levels dynamically. Key aspects include:
- Enables higher power transfer (up to 100W or more, depending on the device and cable).
- Ensures efficient charging by dynamically adjusting voltage and current.
- Commonly used in USB-C chargers, docking stations, and hubs that provide power directly to laptops, tablets, and smartphones.
Example: A USB-C docking station with PD output can charge a connected laptop while simultaneously powering other peripherals. Additionally, these tend to come with their own AC adapter.
What is Pass-Through Power Delivery?
Pass-Through Power Delivery refers to a hub or docking station that does not generate power itself but instead allows power to pass through from an external power adapter. Key aspects include:
- Requires a dedicated power adapter (e.g., a USB-C PD laptop charger) plugged into the docking station or hub.
- Typically, a portion of the incoming power is allocated to the dock’s functionality (such as data transfer and peripheral connections), and the remaining power is sent to the connected laptop or device.
- May reduce the total power available to the laptop compared to direct charging.
Example: A USB-C hub with pass-through PD allows a laptop's original USB-C PD charger to be connected to the hub, which then distributes power to the laptop while also supporting external peripherals.
Choosing the Right Option
- If you need a docking station that can directly charge your laptop, look for one with dedicated Power Delivery (PD) support.
- If your laptop already has a high-wattage charger and you want to maintain power while expanding connectivity, a pass-through PD hub may be a better choice.
- Be mindful of power limitations with pass-through charging, as some hubs may reserve power for their own operation, reducing the power available for the laptop.
Some examples of hubs with PD pass-through would be our USBC-9IN1E with 140w pass-through charging or our smaller USBC-4IN1 with 100w pass-through.
On the flip side, we have our docking stations that power your devices by themselves. Examples such as our UD-7400PD which is capable of 140w of charge and 5 displays.
Understanding these differences will help ensure you select the right docking station or USB-C hub for your setup. If you have any questions or would like a recommendation, feel free to reach out to our support at support@plugable.com
