ltc1069-7is8-trpbf Linear Technology Corporation, ltc1069-7is8-trpbf Datasheet - Page 5

• Manufacturer Part Number: ltc1069-7is8-trpbf
• Description: Low Power, 8th Order Progressive Elliptic, Lowpass Filter
• Manufacturer: Linear Technology Corporation

TYPICAL PERFORMANCE CHARACTERISTICS
PIN
AGND (Pin 1): Analog Ground. The quality of the analog
signal ground can affect the filter performance. For either
single or dual supply operation, an analog ground plane
surrounding the package is recommended. The analog
ground plane should be connected to any digital ground at
a single point. For dual supply operation Pin 1 should be
connected to the analog ground plane.
For single supply operation Pin 1 should be bypassed to the
analog ground plane with a 0.47 F or larger capacitor. An
internal resistive divider biases Pin 1 to 1/2 the total power
supply. Pin 1 should be buffered if used to bias other ICs.
Figure 1 shows the connections for single supply operation.
U
5
4
3
2
1
0
0
Supply Current vs Supply Voltage
Figure 1. Connections for Single Supply Operation
f
FUNCTIONS
CLK
= 10Hz
1
TOTAL SUPPLY VOLTAGE ( V)
U
85 C
STAR
SYSTEM
GROUND
V
2
0.1 F
0.47 F
IN
25 C
V
ANALOG GROUND PLANE
+
3
U
–40 C
1
2
3
4
GROUND
DIGITAL
PLANE
AGND
V
NC
V
4
IN
+
LTC1069-1
W
5
V
1069-1 G13
CLK
OUT
NC
V
–
U
SOURCE
CLOCK
6
8
7
6
5
1k
V
OUT
1069-1 F01
5.0
4.5
4.0
3.5
3.0
2.5
2.0
0.1
Supply Current vs Clock
Frequency
0.2
0.3 0.4
CLOCK FREQUENCY (MHz)
V
V
V
0.5
S
S
S
= 3.3V
= 5V
= 5V
0.6
V
the V
to an adequate analog ground. The filter’s power supplies
should be isolated from other digital or high voltage
analog supplies. A low noise linear supply is recom-
mended. Using switching power supplies will lower the
signal-to-noise ratio of the filter. Unlike previous mono-
lithic filters, the power supplies can be applied at any
order, that is, the positive supply can be applied before the
negative supply and vice versa. Figure 2 shows the con-
nection for dual supply operation.
+
0.7
, V
0.8
–
–
(Pin 7) should be bypassed with a 0.1 F capacitor
(Pins 2, 7): Power Supply Pins. The V
Figure 2. Connections for Dual Supply Operation
0.9
1069-1 G14
1.0 1.2
STAR
SYSTEM
GROUND
V
+
0.1 F
ANALOG GROUND PLANE
V
IN
1
2
3
4
GROUND
DIGITAL
PLANE
–2
–3
–4
–5
–1
AGND
V
NC
V
5
4
3
2
1
0
IN
+
LTC1069-1
Output Voltage Swing vs
Temperature
–40
V
CLK
OUT
–20
NC
V
AMBIENT TEMPERATURE ( C)
–
SOURCE
8
7
6
5
CLOCK
0
V
LTC1069-1
1k
OUT
0.1 F
20
V
1069-1 F02
–
+
40
(Pin 2) and
V
V
V
V
S
V
S
S
V
S
S
S
= 1.57V
= 1.57V
= 2.5V
= 2.5V
= 5V
60
= 5V
1069-1 G15
5
80