Mobile devices have become an integral part of our daily lives. As we grow accustomed to mobile technological devices in our everyday life, it is crucial to keep them functional (charged) throughout the day. Fast charging technologies, such as PowerDelivery (PD), come to the rescue, and we will discuss it further below.

The non-profit organization USB Implementers Forum (USB-IF), which includes such tech giants as IBM, Intel, Microsoft, NEC, Compaq, Digital, and Nortel, is responsible for the implementation of USB standards. One of these standards is Power Delivery. Despite the fact that this technology can deliver up to 100W to the consumer, today, for everyday practical use — charging mobile gadgets (smartphones, tablets, etc.) — a charger with a maximum voltage of up to 15V, current of up to 3A, and power of up to 27W is sufficient.

Working principle:

As for selecting the optimal charging characteristics, the PD standard specification defines two operating mechanisms for a USB charger that it can offer to connected devices:

• A list of fixed voltage (V) values, each with a maximum current (A). The connected device selects the voltage and current from this list. This is a traditional model for devices that have built-in electronics to manage their battery charging, including adjusting the voltage and current that actually reach the battery. A side effect of this model is heat generation in the charging circuit, which can be an issue for small form-factor devices.


• A list of multiple programmable voltage (V) ranges, each with a maximum current (A). The connected device requests a voltage (in 20 mV increments) that falls within the required range and with the maximum current. The USB charger supplies the required voltage until the maximum current is reached, after which the USB charger decreases its output voltage to avoid exceeding the required maximum current. During the charging cycle, when a 'portion' of the highest current value is supplied, the USB charger can connect directly (through an appropriate safety device) to the battery. This model is used by devices that aim to minimize thermal impact on their internal charging circuits.

Thus, the gadget itself specifies to the power source what current and voltage need to be supplied. If PD is not supported by the gadget, the minimum charging characteristics will be selected. Similar principles are also used in other fast charging technologies, such as Qualcomm QuickCharge, Samsung AdaptiveFastCharger, Pump Express, and others.

Advantages and disadvantages

The main advantage, undoubtedly, is fast charging. For example, as of today, full PD support is already available in Apple devices (starting from iPhone 8) and Google devices (starting from Google Pixel), allowing their phones to reach a 50% charge in less than 30 minutes, and achieving a full charge up to four times faster than with regular chargers.

Disadvantages include the probable depletion of the battery from frequent use of fast chargers, although there are many disputes about this.

REAL-EL chargers with USB Power Delivery technology:

The lineup of chargers has been updated with new models that support USB Power Delivery 3.0 and Qualcomm QuickCharge 3.0. We would particularly like to highlight the REAL-EL CH-350, which combines both of these standards in one device.

REAL-EL CH-350

Characteristics:

• Types of connectors: USB type C, USB type A
• Input voltage: AC 100-240V 50-60Hz
• Output Qualcomm Quick Charge 3.0: DC 3.6V-6.5V 3A / 6.5V-9V 2A / 9V-12V 1.5A
• Output USB Type-C Power Delivery 27W: DC 5V 3A / 9V 3A / 12V 2.25A

• For connecting to a USB Type C port, the REAL-EL USB 3.0 Type C-Type C cable is an ideal choice.


• We also remind you that REAL-EL offers a wide range of cable products.