User manual

Setup and Installation
© 2006 Microchip Technology Inc. DS51614A-page 15
2.5.3 Sallen-Key, High-pass Filter Sections
TABLE 2-2: IMPEDANCES FOR SALLEN-KEY, HIGH-PASS FILTER
SECTIONS
FIGURE 2-8: Sallen-Key, High-pass (modified) Filter Topologies.
Topology SK-HP1 SK-HP2 SK-HP1-K SK-HP2-K
Z
1
0Ω C11 0Ω C11
Z
2
C11 C12 C11 C12
Z
3
—R11—R11
Z
4
R11 R12 R11 R12
Z
5
————
Z
6
————
Z
7
——0Ω 0Ω
Z
8
————
Z
9
————
Z
10
——RaRa
Z
11
0Ω 0Ω Rb Rb
U
1
C11
R11
V
IN
V
OUT
V
DD
SK-HP1
U
1
C11
R11
V
IN
V
OUT
V
DD
SK-HP2
C12
R12
V
DD
/2
V
DD
/2
U
1
V
IN
V
OUT
V
DD
SK-HP1-K
SK-HP2-K
C11
R11
U
1
C11
R11
V
IN
V
OUT
V
DD
C12
R12
Ra Rb
V
DD
/2
Ra Rb
V
DD
/2