2 layers76.5 × 66.3 mm Diamond, the printed circuit board in 3D

Diamond

A simple diamond buffer amplifier

Size: 76.5 × 66.3 mm
Copper layers: 2
Thickness: 1.6 mm
Parts: 40
Nets: 19
Pads: 87
Tracks, vias: 193, 0
Routed: Yes
KiCad: KiCad 9.0 (file 20241229)
Created: 2 Apr 2025
Updated: 7 Apr 2025

Overview

Diamond is an open-source printed circuit board by prydin, from the prydin/diamond-buffer-amp repository on GitHub. It is a 2-layer board of 76.5 × 66.3 mm with 40 parts on 19 nets, routed with 193 tracks and 0 vias.

It is built around the NE5532, BD139 and BD140, with the NJW0281G and NJW0302G among its other parts. Its parts include 12 resistors, 10 capacitors, 6 connectors, 4 transistors and 2 diodes.

Main components

README

README.md

A very simple diamond buffer audio amplifier

*** WORK IN PROGRESS ***

Abstract

This design is based on an idea by the user No ideas (yes, that's really his handle) at diyaudio.com. It's a very simple design based on an opamp (NE5532 in this case) and a diamond buffer. It has not yet been built, but it's showing promising performance in simulations. Check back for more details once a prototype has been built!

Parts

Qty	Value	Footprint	References
5	~	Diamond:Spade Connector	J2, J3, J4, J5, J6
3	100n	Capacitor_THT:C_Rect_L7.2mm_W3.0mm_P5.00mm_FKS2_FKP2_MKS2_MKP2	C6, C7, C8
2	0.5	Resistor_THT:R_Axial_DIN0414_L11.9mm_D4.5mm_P20.32mm_Horizontal	R8, R9
2	1.5k	Resistor_THT:R_Axial_DIN0414_L11.9mm_D4.5mm_P20.32mm_Horizontal	R1, R2
2	10	Resistor_THT:R_Axial_DIN0204_L3.6mm_D1.6mm_P7.62mm_Horizontal	R5, R6
2	100u	Capacitor_THT:CP_Radial_D8.0mm_P5.00mm	C11, C12
1	10	Resistor_THT:R_Axial_DIN0414_L11.9mm_D4.5mm_P20.32mm_Horizontal	R11
1	100	Resistor_THT:R_Axial_DIN0204_L3.6mm_D1.6mm_P7.62mm_Horizontal	R12
1	1000u	Capacitor_THT:C_Radial_D12.5mm_H20.0mm_P5.00mm	C2
1	10k	Resistor_THT:R_Axial_DIN0204_L3.6mm_D1.6mm_P7.62mm_Horizontal	R4
1	1N4004	Diode_THT:D_DO-41_SOD81_P10.16mm_Horizontal	D2
1	1N4148	Diode_THT:D_DO-35_SOD27_P7.62mm_Horizontal	D1
1	1k	Diamond:TRIM_T93YA103KT20	RV1
1	1k	Resistor_THT:R_Axial_DIN0204_L3.6mm_D1.6mm_P7.62mm_Horizontal	R3
1	220p	Capacitor_THT:C_Rect_L7.2mm_W3.0mm_P5.00mm_FKS2_FKP2_MKS2_MKP2	C4
1	220u	Capacitor_THT:CP_Radial_D8.0mm_P5.00mm	C1
1	22p	Capacitor_THT:C_Rect_L7.2mm_W3.0mm_P5.00mm_FKS2_FKP2_MKS2_MKP2	C3
1	4.7u	Capacitor_THT:CP_Radial_D4.0mm_P2.00mm	C5
1	470	Resistor_THT:R_Axial_DIN0204_L3.6mm_D1.6mm_P7.62mm_Horizontal	R7
1	47k	Resistor_THT:R_Axial_DIN0204_L3.6mm_D1.6mm_P7.62mm_Horizontal	R10
1	BD139	Package_TO_SOT_THT:TO-126-3_Vertical	Q1
1	BD140	Package_TO_SOT_THT:TO-126-3_Vertical	Q2
1	INPUT	TerminalBlock_4Ucon:TerminalBlock_4Ucon_1x02_P3.50mm_Horizontal	J1
1	NE5532	Package_DIP:DIP-8_W7.62mm	U1
1	NJW0281G	Package_TO_SOT_THT:TO-3P-3_Vertical	Q3
1	NJW0302G	Package_TO_SOT_THT:TO-3P-3_Vertical	Q4

The 36 most common of 40 parts.

Questions

How big is the Diamond PCB?

It measures 76.5 × 66.3 mm and has 2 copper layers, 1.6 mm thick.

What parts does the Diamond use?

40 parts, built around the NE5532, BD139, BD140 and NJW0281G. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.

Where can I download the Diamond KiCad files?

From the prydin/diamond-buffer-amp repository on GitHub, at the commit this page was made from: the board is kicad/diamond.kicad_pcb and its schematic kicad/diamond.kicad_sch. PCBKit opens the board in the browser, with nothing to install.

Can I use the Diamond design in my own project?

Its repository states no licence, so its author keeps all rights: ask prydin before reusing the design.

Project files

Show this board on your page

A live frame, for any web page

<iframe src="https://pcbkit.io/embed/boards/prydin-diamond-buffer-amp" title="Diamond in PCBKit" width="100%" height="480" style="border:0;border-radius:12px" allow="fullscreen" loading="lazy"></iframe>

A picture

<img src="https://pcbkit.io/embed/boards/prydin-diamond-buffer-amp.jpg" alt="Diamond" width="1200" height="900">

A picture that opens the board, for a README

[![Diamond](https://pcbkit.io/embed/boards/prydin-diamond-buffer-amp.jpg?size=s)](https://pcbkit.io/boards/prydin-diamond-buffer-amp)

Source

Repository: prydin/diamond-buffer-amp
Board file: kicad/diamond.kicad_pcb
Commit: 4277712
Licence: Not stated

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