Table of Contents

Multi lowpass filter

Multiple RC lowpass filters with different cutoff frequencies to switch between.

Application

  1. Vibration sensitivity measurement
  2. Errorsignal for Locks

Status

:OK:: tested and working, :Ok:: minor issue/not tested, :no:: defect

# Status Comment
1 :OK:
2 :OK:
3 :OK:
4 :OK:
5 :OK:
6 :OK:
7 :OK:
8 :OK:
9 :OK:
10 :OK:
11 :OK:

Setup

Switch: Elma 01-1104 (with gold inside), Farnell # 1876072

\(f_{c}\): cutoff frequency, \(\tau\): time constant, R: resistance, C: capacitance

\[ f_{c} = \frac{1}{2 \pi \tau} \quad with \quad \tau = RC\]

Cutoff Frequency [Hz ] Time Constant [ms] Capacitance [nF] Capacitor
4.8 33 3300 WIMA 3,3µF 50- F6
16 10 1000 WIMA MKS4 1,0µF 100-
48 3.3 330 WIMA MKC4 0.33/100-
160 1 100 µ1K100
480 0.33 33 33nK100
1600 0.1 10 10nK100

Prototype

Multi RC lowpass filters by PTB