Pocket link

anshkumar·pocket-link·revA/kicad/pocket-link.kicad_pcb

About the Pocket link PCB

Pocket link is an open source RP2040/RP2350 PCB design by anshkumar, published on GitHub under the Apache-2.0 license. It is a 4-layer board measuring 31 × 16 mm, with 31 components from 14 distinct parts.

Its main chip is the RP2040, from the RP2040/RP2350 family. Other key parts include the W25Q16JVSNIQ, AP2112K-3.3TRG1 and USBLC6-2SC6. By type, the board carries 18 capacitors, 6 resistors, 4 ICs, 1 crystal, 1 connector and 1 diode.

It belongs with the audio and iot & wireless designs in this gallery.

From the project

Open hardware: a USB-C adapter that lets a Pocket bot hear and speak on an Android phone's own calls. Board (CERN-OHL-P-2.0), RP2040 firmware and protocol (Apache-2.0).

A small USB-C dongle that plugs into the phone. The phone sees it as a USB headset, so Android routes call audio to it. It also exposes a data channel that the Pocket app uses to stream that audio to and from the voice agent over the phone's own internet. There is no Bluetooth, no Wi-Fi and no battery.

Status: design complete, DRC clean, not yet fabricated or tested.

Main components on the Pocket link

RP2040 W25Q16JVSNIQ AP2112K-3.3TRG1 USBLC6-2SC6

Pocket link bill of materials (BOM)

31 components, 14 distinct parts — part numbers from the project's BOM.

Qty	Part	Footprint	Refs
1	RP2040 Raspberry Pi	QFN-56-1EP_7x7mm_P0.4mm_EP3.2x3.2mm_Vias0.3	U1
1	W25Q16JVSNIQ Winbond	SOIC-8_3.9x4.9mm_P1.27mm	U2
1	AP2112K-3.3TRG1 AP2112K-3.3 Diodes Inc	SOT-23-5	U3
1	USBLC6-2SC6 ST	SOT-23-6	U4
1	X322512MSB4SI 12MHz YXC	Crystal_SMD_3225-4Pin_3.2x2.5mm	Y1
1	105444-0001 USB-C plug Molex	USB_C_Plug_Molex_105444	J1
1	19-217/GHC-YR1S2/3T GREEN Everlight	LED_0603_1608Metric	D1
3	CL05A105KA5NQNC 1uF Samsung	C_0402_1005Metric	C1, C20, C21
1	CL10A106KP8NNNC 10uF Samsung	C_0603_1608Metric	C2
12	CL05B104KO5NNNC 100nF Samsung	C_0402_1005Metric	C10, C11, C12, C13, C14, C15, C16, C17 +4
2	0402CG330J500NT 33pF FH	C_0402_1005Metric	C24, C25
1	0402WGF5101TCE 5.1k UNI-ROYAL	R_0402_1005Metric	R1
2	0402WGF270JTCE 27R UNI-ROYAL	R_0402_1005Metric	R2, R3
3	0402WGF1001TCE 1k UNI-ROYAL	R_0402_1005Metric	R4, R5, R6

Pocket link design files

The KiCad project lives in the anshkumar/pocket-link repository on GitHub; these links point at the commit this page was built from.

LayoutrevA/kicad/pocket-link.kicad_pcb
SchematicrevA/kicad/pocket-link.kicad_sch
BOMrevA/fab/BOM_full.csv

Pocket link: common questions

What microcontroller does the Pocket link use?

The Pocket link is built around the RP2040, from the RP2040/RP2350 family.

How big is the Pocket link PCB?

The Pocket link measures 31 × 16 mm, has 4 copper layers and is 0.8 mm thick.

How many components are on the Pocket link?

31 components, from 14 distinct parts, with part numbers taken from the project's own BOM. The full bill of materials is listed on this page.

Where can I download the Pocket link design files?

From the anshkumar/pocket-link repository on GitHub, which has the KiCad layout, the schematic and the BOM; the links under Design files point to each one.

Can I use the Pocket link design in my own project?

Yes, under the terms of its Apache-2.0 license, which anshkumar chose for the repository.

Can I test firmware for the Pocket link without the hardware?

Yes. HardLabs builds a simulation of the board from its netlist and BOM, so you can run and debug RP2040/RP2350 firmware against it before you order a PCB.