2 layers140.5 × 130.6 mm Diode ladder filter, the printed circuit board in 3D

Diode ladder filter

Size: 140.5 × 130.6 mm
Copper layers: 2
Thickness: 1.6 mm
Parts: 81
Nets: 53
Pads: 205
Tracks, vias: 365, 0
Routed: Yes
KiCad: KiCad 10.0 (file 20260206)
Created: 22 Nov 2025
Updated: 7 Nov 2026

Overview

Diode ladder filter is an open-source printed circuit board by gridbugs, from the gridbugs/modular2 repository on GitHub, published under the MIT licence. It is a 2-layer board of 140.5 × 130.6 mm with 81 parts on 53 nets, routed with 365 tracks and 0 vias.

Its parts include 23 resistors, 12 capacitors, 12 diodes, 12 connectors and 4 switches.

README

low-pass-filter/README.md

Low-pass Filter

Quirks

V1

The "Cutoff" potentiometer is reversed.

Parts

Qty	Value	Footprint	References
12	D	Diode_THT:D_A-405_P7.62mm_Horizontal	D1, D2, D3, D4, D5, D6, D7, D8, D9, D10, D11, D12
8	33K	Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal	R9, R10, R12, R15, R16, R17, R18, R23
8	MountingHole_3.2mm_M3	MountingHole:MountingHole_3.2mm_M3	H1, H2, H3, H4, H5, H6, H7, H8
5	1nF	Capacitor_THT:C_Disc_D4.3mm_W1.9mm_P5.00mm	C1, C2, C6, C7, C8
4	100nF	Capacitor_THT:C_Disc_D4.3mm_W1.9mm_P5.00mm	C3, C4, C9, C11
4	1K	Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal	R5, R14, R19, R21
3	10K	Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal	R3, R4, R8
2	1uF	Capacitor_THT:C_Disc_D4.3mm_W1.9mm_P5.00mm	C10, C12
2	220K	Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal	R20, R22
2	2K	Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal	R11, R13
2	CV1	modular2:banana-jack	J3, J8
2	CV2	modular2:banana-jack	J4, J9
2	Input	modular2:banana-jack	J5, J10
2	Output	modular2:banana-jack	J6, J11
2	Power	Connector_IDC:IDC-Header_2x03_P2.54mm_Vertical	J1, J2
2	TL074	Package_DIP:DIP-14_W7.62mm_Socket	U1, U2
1	100K - CV1 Scale	Potentiometer_THT:Potentiometer_Alps_RK09K_Single_Vertical	RV2
1	100K - CV2 Scale	Potentiometer_THT:Potentiometer_Alps_RK09K_Single_Vertical	RV4
1	100K - Cutoff	Potentiometer_THT:Potentiometer_Alps_RK09K_Single_Vertical	RV1
1	100K - Envelope Soften	Potentiometer_THT:Potentiometer_Alps_RK09K_Single_Vertical	RV5
1	100K - Input Scale	Potentiometer_THT:Potentiometer_Alps_RK09K_Single_Vertical	RV6
1	100K - Output Scale	Potentiometer_THT:Potentiometer_Alps_RK09K_Single_Vertical	RV7
1	100K - Resonance	Potentiometer_THT:Potentiometer_Alps_RK09K_Single_Vertical	RV3
1	10uF	Capacitor_THT:C_Disc_D4.3mm_W1.9mm_P5.00mm	C5
1	1k	Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal	R7
1	24K	Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal	R1
1	3k3	Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal	R6
1	47K	Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal	R2
1	BPF	modular2:switch1	SW4
1	Conn_01x04_Pin	Connector_PinHeader_2.54mm:PinHeader_1x04_P2.54mm_Vertical	J12
1	Conn_01x04_Socket	Connector_PinSocket_2.54mm:PinSocket_1x04_P2.54mm_Vertical	J7
1	HPF	modular2:switch1	SW3
1	LOGO	modular2:ibis-small	G***
1	LPF	modular2:switch1	SW2
1	Resonance_safety	modular2:switch1	SW1

Questions

How big is the Diode ladder filter PCB?

It measures 140.5 × 130.6 mm and has 2 copper layers, 1.6 mm thick.

What parts does the Diode ladder filter use?

81 parts. 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 Diode ladder filter KiCad files?

From the gridbugs/modular2 repository on GitHub, at the commit this page was made from: the board is diode-ladder-filter/diode-ladder-filter.kicad_pcb and its schematic arduino-delay/arduino-delay.kicad_sch. PCBKit opens the board in the browser, with nothing to install.

Can I use the Diode ladder filter design in my own project?

Its repository publishes it under the MIT licence: you may reuse it on that licence's terms (keep the author's notice, and for a copyleft licence share your changes alike).

Project files

Show this board on your page

A live frame, for any web page

<iframe src="https://pcbkit.io/embed/boards/gridbugs-modular2-diode-ladder-filter" title="Diode ladder filter 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/gridbugs-modular2-diode-ladder-filter.jpg" alt="Diode ladder filter" width="1200" height="900">

A picture that opens the board, for a README

[![Diode ladder filter](https://pcbkit.io/embed/boards/gridbugs-modular2-diode-ladder-filter.jpg?size=s)](https://pcbkit.io/boards/gridbugs-modular2-diode-ladder-filter)

Source

Repository: gridbugs/modular2
Board file: diode-ladder-filter/diode-ladder-filter.kicad_pcb
Commit: 81bdd24
Licence: MIT

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