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HeadphoneGuitarPracticeAmp

jbush001·HeadphoneGuitarPracticeAmp·logic_board/logic_board.kicad_pcb

HeadphoneGuitarPracticeAmp PCB layout, top view — open source STM32 board by jbush001

About the HeadphoneGuitarPracticeAmp PCB

HeadphoneGuitarPracticeAmp is an open source STM32 PCB design by jbush001, published on GitHub under the Apache-2.0 license. It is a 4-layer board measuring 80 × 30 mm, with 51 components from 28 distinct parts.

Its main chip is the STM32G474CET6, from the STM32 family. Other key parts include the OPA340NA, WM8731SEDS_V, SPX3819M5-L-3-3 and BQ24090DGQR. By type, the board carries 20 capacitors, 11 resistors, 5 ICs, 5 connectors, 5 switches and 3 diodes.

It belongs with the audio and power & battery designs in this gallery.

From the project

Portable headphone amplifier/effects processor for electric guitar practice.

I was looking for a headphone guitar amp with the following features:

- Integrated guitar plug: Doesn't require an extra cable or have a box flopping around. - Rechargeable battery - Flexible set of basic effects with decent quality: distortion, reverb, amp simulation, etc. - Built-in metronome

Although there are commercially available headphone amps that support a few of these, surprisingly, none supported all of them, so I decided to build my own. The heart of this is an ARM microcontroller, which processes the audio signal and applies digital effects. The hardware consists of a custom…

HeadphoneGuitarPracticeAmp, from the project README
From the project README

Main components on the HeadphoneGuitarPracticeAmp

STM32G474CET6OPA340NAWM8731SEDS_VSPX3819M5-L-3-3BQ24090DGQR

HeadphoneGuitarPracticeAmp bill of materials (BOM)

51 components, 28 distinct parts — part numbers from the project's BOM.

QtyPartRefs
1
STM32G474CET6
U1
1
OPA340NA
U2
1
WM8731SEDS_V
U3
1
SPX3819M5-L-3-3
U4
1
BQ24090DGQR
U5
1
8 MHz
Y1
1
12MHz
Y2
1
Debug
J1
1
Audio In
J2
1
SJ2-3595X-SMT
J3
1
Amphenol 124015
J4
1
Batt
J5
4
TL3315NF160Q
SW1, SW2, SW3, SW4
1
Power
SW5
2
LED
D1, D2
1
Debug
D3
2
22uF
C3, C25
3
10uF
C4, C13, C26
12
0.1uF
C5, C6, C7, C8, C10, C12, C15, C16 +4
1
10uF
C9
Show 8 more
QtyPartRefs
2
220uF
C23, C24
2
5.1k
R1, R2
1
50k
R6
1
100k
R7
2
47k
R9, R10
1
1k
R13
1
2k
R14
3
1.5k
R16, R17, R18

HeadphoneGuitarPracticeAmp design files

The KiCad project lives in the jbush001/HeadphoneGuitarPracticeAmp repository on GitHub; these links point at the commit this page was built from.

HeadphoneGuitarPracticeAmp: common questions

What microcontroller does the HeadphoneGuitarPracticeAmp use?

The HeadphoneGuitarPracticeAmp is built around the STM32G474CET6, from the STM32 family.

How big is the HeadphoneGuitarPracticeAmp PCB?

The HeadphoneGuitarPracticeAmp measures 80 × 30 mm, has 4 copper layers and is 1.6 mm thick.

How many components are on the HeadphoneGuitarPracticeAmp?

51 components, from 28 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 HeadphoneGuitarPracticeAmp design files?

From the jbush001/HeadphoneGuitarPracticeAmp repository on GitHub, which has the KiCad layout and the BOM; the links under Design files point to each one.

Can I use the HeadphoneGuitarPracticeAmp design in my own project?

Yes, under the terms of its Apache-2.0 license, which jbush001 chose for the repository.

Can I test firmware for the HeadphoneGuitarPracticeAmp without the hardware?

Yes. HardLabs builds a simulation of the board from its netlist and BOM, so you can run and debug STM32 firmware against it before you order a PCB.

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