ChatDiagram
CIRCUIT · BUTTERWORTH LOW PASS FILTER

Second-Order Butterworth Low-Pass Filter Circuit Diagram Examples

The second-order Butterworth low-pass filter is a cornerstone of analog signal processing, offering a maximally flat passband and a predictable -40 dB/decade roll-off. On this page, you’ll find a collection of circuit diagrams for second-order Butterworth low-pass filters, including popular Sallen-Key and multiple-feedback topologies. These examples are ideal for electronics engineers, students, and hobbyists designing audio crossovers, anti-aliasing filters, and sensor signal conditioning circuits.

4 EXAMPLES· UPDATED 2026-09-19
Make your own butterworth low pass filter diagram.

Describe it in plain English — the AI drafts it, you edit. No template wrangling.

Make your own →
ANALOG FILTER

Second-Order Butterworth Low-Pass Filter

ELECTRONICS

Sallen-Key Second-Order Butterworth Low-Pass Filter

ELECTRONICS

Second-Order Butterworth Low-Pass Filter

ELECTRONICS

Second-Order Butterworth Low-Pass Filter

ABOUT

About these examples.

Each diagram is rendered with ChatDiagram’s circuit diagram tool, so you can easily edit component values, adjust the topology, or export a high-resolution image for your documentation.

Whether you need a unity-gain Sallen-Key implementation or a gain stage with a multiple-feedback architecture, these circuits are ready to adapt. Use the generator below to create your own second-order Butterworth low-pass filter diagram in minutes.

HOW TO

Make one yourself.

  1. 1

    Select a second-order Butterworth low-pass filter template

    Start from a pre-built Sallen-Key or multiple-feedback circuit to save time.

  2. 2

    Adjust component values

    Change resistor and capacitor values to set your desired cutoff frequency and Q factor (typically 0.707 for Butterworth).

  3. 3

    Connect the signal path

    Ensure the input, op-amp, and output are properly wired according to the chosen topology.

  4. 4

    Add annotations

    Label nodes, component values, and the filter response to make the diagram self-explanatory.

  5. 5

    Export or share

    Download as SVG, PNG, or share a live link to collaborate with your team.

FAQ

Frequently asked questions

What is a second-order Butterworth low-pass filter?01
A second-order Butterworth low-pass filter is an active filter that provides a maximally flat passband and a roll-off of -40 dB per decade above the cutoff frequency. It typically uses one operational amplifier and a few resistors and capacitors.
What is the difference between Sallen-Key and multiple-feedback topologies?02
The Sallen-Key topology uses a non-inverting op-amp configuration and is simple with low component count, while the multiple-feedback topology uses an inverting configuration and can provide gain, often with better stopband performance.
How do I calculate component values for a second-order Butterworth filter?03
For a second-order Butterworth response, set the quality factor Q to 0.707. You can choose a cutoff frequency and then calculate resistor and capacitor values using standard formulas or use a design tool like ChatDiagram to generate them automatically.
What is the cutoff frequency of a Butterworth filter?04
The cutoff frequency is the point where the filter's response drops to -3 dB relative to the passband. For a second-order Butterworth low-pass filter, the response is -3 dB at the cutoff and continues to fall at -40 dB per decade.
Can I use a single-supply op-amp for a second-order Butterworth filter?05
Yes, single-supply operation is possible by biasing the op-amp's non-inverting input to a mid-supply voltage and AC-coupling the input and output. The circuit diagrams on this page can be adapted for single-supply designs.
Start from a blank canvas →

Open the AI editor and describe what you need — export PNG/SVG when you're done.

Make your own →