10
LTC1569-7
Single 3V Operation, AC Coupled Input,
128kHz Cutoff Frequency
18
27
36
45
V
OUT
V
IN
1µF
3V
R
EXT
= 10k
1µF
0.1µF
2k
3.48k
3V
1569-7 TA02
LTC1569-7
IN
+
IN
–
GND
V
–
OUT
V
+
R
X
DIV/CLK
f
CUTOFF
=
n = 1, 4, 16 FOR PIN 5 AT
GROUND, OPEN, V
+
128kHz
n = 1
()
10k
R
EXT
()
18
27
36
45
V
OUT
V
IN
1µF
3V
R
EXT
= 10k
100pF
1µF
2k
3.48k
3V
1569-7 TA04
LTC1569-7
IN
+
IN
–
GND
V
–
OUT
V
+
R
X
DIV/CLK
f
CUTOFF
=
n = 1, 4, 16 FOR PIN 5 AT
GROUND, OPEN, V
+
128kHz
n = 4
()
10k
R
EXT
()
Single 3V Supply Operation, DC Coupled,
32kHz Cutoff Frequency
Single 5V Operation, 300kHz Cutoff Frequency,
DC Coupled Differential Inputs with Balanced Input Impedance
18
27
36
45
V
OUT
V
IN
+
V
IN
–
1µF
5V
R
EXT
= 4.1k
1µF
27k
5V
1569-7 TA03
IN
GND
OUT
LT
®
1460-2.5
(SOT-23)
LTC1569-7
f
CUTOFF
~
n = 1, 4, 16 FOR PIN 5 AT
GROUND, OPEN, V
+
128kHz
n = 1
()
10k
4.1k
()
IN
+
IN
–
GND
V
–
OUT
V
+
R
X
DIV/CLK
TYPICAL APPLICATIO S
U
Single 3V, AC Coupled Input,
128kHz Cutoff Frequency
FREQUENCY (Hz)
0 300k
80k 100k 160k 180k 240k 260k120k 140k 200k 220k 280k
GAIN (dB)
GROUP DELAY
1569-7 TA02a
0
–10
–20
–30
–40
–50
–60
–70
–80
–90
16µs
14µs
12µs
140k0 20k 80k 100k40k 60k 120k
every clock period. Therefore, the sampling frequency is
twice the clock frequency and 64 times the filter cutoff
frequency. Input signals with frequencies near 2 • f
CLK
± f
CUTOFF
will be aliased to the passband of the filter and
appear at the output unattenuated.
Power Supply Current
The power supply current depends on the operating mode.
When the LTC1569-7 is in the divide-by-1 mode, or when
clocked externally, the supply current is reduced by 50%
for supply voltages below 4V. For the divide-by-4 and
divide-by-16 modes, the supply current is reduced by
60% relative to the current when clocked externally,
independent of the power supply voltage. Power supply
current versus cutoff frequency for various operating
modes is shown in the “Typical Performance Characteris-
tics” section.
APPLICATIONS INFORMATION
WUU
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