Datasheet

_________________________________________________________________ Maxim Integrated Products 3
MAX44265 Evaluation Kit
Evaluates: MAX44265
Lowpass Sallen-Key Filter
To configure the Sallen-Key as a lowpass filter, populate
the R2 and R8 pads with resistors and the C3 and C4
pads with capacitors. The corner frequency and Q are
then given by:
C
1
f
2 R2 C3 R8 C4
=
π × × ×
R2 C3 R8 C4
Q
C4(R2 R8)
× × ×
=
+
Highpass Sallen-Key Filter
To configure the Sallen-Key as a highpass filter, populate
the C3 and C4 pads with resistors and the R2 and R8
pads with capacitors. The corner frequency and Q are
then given by:
C
R8 C4 R2 C3
1
f
2 C R C R
=
π × × ×
R8 C4 R2 C3
R3 R2 R8
C R C R
Q
R (C C )
× × ×
=
+
Capacitive Loads
Some applications require driving large capacitive loads.
To improve the stability of the amplifier in such cases,
replace R6 with a suitable resistor value to improve
amplifier phase margin in the presence of the capacitive
load (C9), or apply a resistive load in parallel with C9.