2 layers128.8 × 110 mm
4 layers38.5 × 100 mm
A state variable filter module for Eurorack
- Size
- 38.5 × 100 mm
- Copper layers
- 4
- Thickness
- 1.6 mm
- Parts
- 75
- Nets
- 62
- Pads
- 219
- Tracks, vias
- 353, 39
- Pours
- 2
- Routed
- Yes
- KiCad
- KiCad 9.0 (file 20241229)
- Created
- 12 Nov 2025
- Updated
- 13 Feb 2026
Overview
Svf-1 is an open-source printed circuit board by xdylanm, from the xdylanm/state-variable-filter repository on GitHub, published under the MIT licence. It is a 4-layer board of 38.5 × 100 mm with 75 parts on 62 nets, routed with 353 tracks and 39 vias.
It is built around the LM13700M, TL072 and B140-E3, with the DMMT5401 among its other parts. Its parts include 34 resistors, 16 capacitors, 9 connectors, 3 ICs and 2 diodes. It belongs with the audio and music boards of this library.
Main components
4
LM13700M
SOIC-16-16V~-4.75V、4.75V~16V 0℃~+70℃ 110dB 2 2.6mA 20mA 400nA 4mV 50V/us 600nA 9.5V~32V SOIC-16 Operational Amplifier ROHSTexas InstrumentsOperational Amplifier
TL072
SOP-8-18V~18V 0℃~+70℃ 1.4mA 1.5nA 10V/us 10mV 2 2.5nA 3MHz 85dB SOP-8 Operational Amplifier ROHSGcoreOperational Amplifier
B140-E3
SMA(DO-214AC)-65℃~+150℃ 1 Independent 1A 200uA@40V 30A 40V 520mV@1A SMA(DO-214AC) Schottky Diodes ROHSVishay IntertechnologySchottky Diodes
DMMT5401
SOT-26(SC74R)-55℃~+150℃ 150V 2 PNP 200mA 200mV 300MHz 300mW 50uA 5V 60 PNP SOT-26(SC74R) Bipolar (BJT) ROHSDiodes IncorporatedBipolar (BJT)
README
README.mdState Variable Filter
The state variable filter is a second order (12dB/oct) filter with low-, high- and band-pass outputs and adjustable resonance. This is a classic filter design that appears in a number of synths, including the Oberheim SEM.
Parts
75| Qty | Value | Footprint | References |
|---|---|---|---|
| 8 | 100k | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R1, R2, R4, R6, R11, R14, R16, R18 |
| 8 | 100n | Capacitor_SMD:C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | C7, C8, C9, C10, C11, C12, C13, C14 |
| 8 | MonoJack | AudioJacks:Jack_3.5mm_QingPu_WQP-PJ301M-12_Vertical | J1, J2, J3, J4, J5, J6, J7, J8 |
| 5 | 220R | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R7, R8, R13, R15, R28 |
| 5 | B100k | Audio_Potentiometer_THT:Potentiometer_Bourns_PTV09A-1_Single_Vertical_thin | RV1, RV2, RV3, RV4, RV5 |
| 4 | 1k | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R5, R10, R19, R20 |
| 4 | 82k | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R23, R24, R25, R26 |
| 3 | 15k | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R9, R17, R27 |
| 2 | 100k | Potentiometer_THT:Potentiometer_Bourns_3296W_Vertical | RV7, RV8 |
| 2 | 10R | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R31, R32 |
| 2 | 10k | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R21, R22 |
| 2 | 10p | Capacitor_SMD:C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | C2, C4 |
| 2 | 10u | Capacitor_THT:CP_Radial_D5.0mm_P2.50mm | C15, C16 |
| 2 | 1M0 | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R33, R34 |
| 2 | 330p | Capacitor_SMD:C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | C3, C5 |
| 2 | B140-E3 | Diode_SMD:D_SMA | D1, D2 |
| 1 | 100R | Potentiometer_SMD:Potentiometer_Bourns_TC33X_Vertical | RV6 |
| 1 | 100p | Capacitor_SMD:C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | C6 |
| 1 | 1u | Capacitor_SMD:C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | C1 |
| 1 | 22k | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R3 |
| 1 | 2k, 3900ppm/C | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | TH1 |
| 1 | 47R | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R12 |
| 1 | 4k7 | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R30 |
| 1 | 560k | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R29 |
| 1 | DMMT5401 | Package_TO_SOT_SMD:SOT-23-6_Handsoldering | Q1 |
| 1 | IDC Header 10P | Connector_IDC:IDC-Header_2x05_P2.54mm_Vertical | J9 |
| 1 | LM13700 | Package_SO:SOIC-16_3.9x9.9mm_P1.27mm | U2 |
| 1 | MountingHole | MountingHole:MountingHole_3.2mm_M3_DIN965 | H1 |
| 1 | TL072 | Package_SO:SOIC-8_3.9x4.9mm_P1.27mm | U3 |
| 1 | TL074 | Package_SO:SOIC-14_3.9x8.7mm_P1.27mm | U1 |
Questions
How big is the Svf-1 PCB?
It measures 38.5 × 100 mm and has 4 copper layers, 1.6 mm thick.
What parts does the Svf-1 use?
75 parts, built around the LM13700M, TL072, B140-E3 and DMMT5401. 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 Svf-1 KiCad files?
From the xdylanm/state-variable-filter repository on GitHub, at the commit this page was made from: the board is hardware/svf-1/svf-1.kicad_pcb and its schematic hardware/svf-1-faceplate/svf-1-faceplate.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the Svf-1 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).
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