Datasheet

LT1806/LT1807
23
18067fc
TYPICAL APPLICATIONS
Single 3V Supply, 4MHz, 4th Order Butterworth Filter
Benefi ting from a low voltage supply operation, low
distortion and rail-to-rail output of LT1806/LT1807, a low
distortion fi lter that is suitable for antialiasing can be built
as shown in Figure 6.
On a 3V supply, the fi lter built with LT1807 has a passband
of 4MHz with 2.5V
P-P
signal and stopband that is greater
than 70dB to frequency of 100MHz. As an option to minimize
the DC offset voltage at the output, connect a series resistor
of 365Ω and a bypass capacitor at the noninverting inputs
of the amplifi ers as shown in Figure 6.
Figure 6. Single 3V Supply, 4MHz, 4th Order Butterworth Filter
+
–
V
S
2
47pF
1/2 LT1807
220pF
665Ω
V
IN
V
OUT
18067 F06
365Ω
(OPTIONAL)
232Ω
232Ω
4.7μF
(OPTIONAL)
+
–
22pF
470pF
562Ω
274Ω
274Ω
1/2 LT1807
Figure 7. Filter Frequency Response
FREQUENCY (Hz)
10k 100k 1M 10M 100M
GAIN (dB)
18067 F07
10
0
–10
–20
–30
–40
–50
–60
–70
–80
–90
V
S
= 3V, 0V
V
IN
= 2.5V
P-P