LTC1069-6CS8 Linear Technology, LTC1069-6CS8 Datasheet - Page 7

• Manufacturer Part Number: LTC1069-6CS8
• Description: IC FILTR 8TH ORDER LOWPASS 8SOIC
• Manufacturer: Linear Technology

Specifications of LTC1069-6CS8

• Filter Type: Elliptic, Lowpass Switched Capacitor
• Frequency - Cutoff Or Center: 14kHz/20kHz
• Number Of Filters: 1
• Max-order: 8th
• Voltage - Supply: 3 V ~ 10 V, ±1.5 V ~ 5 V
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

APPLICATIONS INFORMATION
Temperature Behavior
The power supply current of the LTC1069-6 has a positive
temperature coeffi cient. The GBW product of its internal
op amps is nearly constant and the speed of the device
does not degrade at high temperatures. Figures 4a, 4b
and 4c show the behavior of the passband of the device
for various supplies and temperatures. The fi lter has a
passband behavior which is temperature independent.
Clock Feedthrough
The clock feedthrough is defi ned as the RMS value of the
clock frequency and its harmonics that are present at the
fi lter’s Output (Pin 8). The clock feedthrough is tested with
the Input (Pin 4) shorted to AGND (Pin 1) and depends on
PC board layout and on the value of the power supplies.
With proper layout techniques the values of the clock
feedthrough are shown in Table 2.
Table 2. Clock Feedthrough
Any parasitic switching transients during the rising and
falling edges of the incoming clock are not part of the
clock feedthrough specifi cations. Switching transients
have frequency contents much higher than the applied
clock; their amplitude strongly depends on scope probing
techniques as well as grounding and power supply
bypassing. The clock feedthrough can be reduced by adding
a single RC lowpass fi lter at the Output (Pin 8).
3.3V
10V
5V
V
S
CLOCK FEEDTHROUGH
100μV
170μV
350μV
RMS
RMS
RMS
–2
–1
–1
–2
–1
–2
2
1
2
1
2
1
0
0
0
1
1
1
V
V
V
V
V
V
S
IN
S
IN
S
IN
3
3
4
= SINGLE 3V
= SINGLE 5V
= ±5V
= 0.5V
= 1V
= 1.5V
5
5
7
RMS
RMS
RMS
f
–40°C
10
CUTOFF
7
7
FREQUENCY (kHz)
Figure 4a
FREQUENCY (kHz)
Figure 4b
FREQUENCY (kHz)
Figure 4c
f
CUTOFF
f
CLK
f
13
CLK
9
9
85°C
= 20kHz
= 1MHz
= 750kHz
11
11
–40°C
16
= 15kHz
f
f
CLK
CUTOFF
–40°C
13
19
13
= 500kHz
85°C
= 10kHz
15
15
22
85°C
LTC1069-6
17
17
25
1069-6 F04a
1069-6 F04a
1069-6 F04c
19
28
19
21
21
31
10696fa
7