PocketPD Shrinks 100 Watts of Bench Supply Power to the Palm of Your Hand

The bench power supply is one of the most ubiquitous pieces of test equipment. Yet, its very name includes the primary limitation: it is big enough to need a workbench. A duo engineering team known as CentyLab is shrinking that perception with PocketPD. It brings the flexible capabilities and unique modes of a bench power supply into a device that fits in the palm of your hand.

The PocketPD packs an OLED Display, banana jack outputs, USB-C input, and a rotary knob into a hand-sized 87.0 by 62.0 by 25.5-millimeter package weighing only 81 grams. A Raspberry Pi RP2040 microcontroller with dual-core Arm Cortex M0+ runs the power supply and a critical IC — an AP33772 USB-C sink controller from Diodes Inc.

A USB-C sink controller uses Power Delivery (PD) 3.0's programmable power supply (PPS) protocol to request specific voltage and current combinations. Unlike PD's typical profiles, PPS enables PocketPD to provide standard features found on bench power supplies, like a programmable output voltage or constant current mode.

For example, when a supply operates in constant current mode, the output voltage changes to achieve a specific current output. LEDs famously benefit from a constant current source. Protection features include reverse current, short circuit detection, and a fly-back diode.

You can use the rotary knob to set PocketPD's voltage from 0 to 20 volts and the current limit from 0 to 5 amps. The capabilities depend on the USB-C power supply or battery bank connected. If the supply does not support the PPS protocol, PocketPD lets you choose from standard USB-PD combinations.

You can now download the Arduino-based open-source firmware from the PocketPD GitHub page. CentyLab plans to make the hardware files available later. Visit the PocketPD pre-launch page on Crowd Supply to subscribe to notifications and learn when the pre-order campaign goes live.