Evaulation Board
To make prototyping active filters easier, Comlinear has designed two different active filter evaluation boards. A
schematic of the first board is shown below. It consists of a CLC109 input buffer, followed by four cascaded Sallen
Key filter sections, realized with two dual Op-amps. The board was designed using surface mount components, so
the resistors and capacitors are interchangeable. This board is available in a sample kit from National Semiconductor
as Lit #665504-001. The other board also allows for up to four cascaded biquad sections but restricts the user to
designs using K = 1 since rather than Op-amps, this board uses a quad, unity gain buffer. The board can be ordered
as part number CLC730023 and is fully documented in the CLC114 evaluation board datasheet, available as National
Semiconductor Lit #150114-003 or in the 1997 Comlinear Databook.
Active Filter Evaluation Board
Part Number CLC730061
May 1997
1997 National Semiconductor Corporation
http://www.national.com
Printed in the U.S.A.
N
730061 Active Filter Evaluation Board Schematic
http://www.national.com
2
Lit #660103-001
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circuitry and specifications.
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C2
COMLINEAR
ACTIVE FILTER
CLC730061 REV. B
C4
C3
+
C13
U2
OUT
U3
IN
U1
C1
1
C10
C9
C15
GND1
GND2
GND3
GND4
730061 Layer1 Silk
P1
COMLINEAR
P1
1
P12
P14
P17
P16
P10
P13
P20
P26
P8
P9
P6
P7
P2
P3
P4
P19
P21
P22
P5
P15
P18
P23
P27
P24
P25
730061 Layer2 Silk
PDF 
ZIP