MF10 NSC [National Semiconductor], MF10 Datasheet - Page 9

• Manufacturer Part Number: MF10
• Description: Universal Monolithic Dual Switched Capacitor Filter
• Manufacturer: NSC [National Semiconductor]

2 0 Modes of Operation
The MF10 is a switched capacitor (sampled data) filter To
fully describe its transfer functions a time domain approach
is appropriate Since this is cumbersome and since the
MF10 closely approximates continuous filters the following
discussion is based on the well know frequency domain
Each MF10 can produce a full 2nd order function See Ta-
ble I for a summary of the characteristics of the various
modes
MODE 1 Notch 1 Bandpass Lowpass Outputs
f
f
H
H
H
O
notch
OLP
OBP
ON
e
e
e
e
e
e
Lowpass gain (as f
Bandpass gain (at f
Notch output gain as f
center frequency of the complex pole pair
f
center frequency of the imaginary zero pair
100
f
CLK
notch
or
e
f
CLK
50
f
O
(See Figure 7 )
e
f
f
O
0)
)
e b
e b
0
f
CLK
R3
R1
R2
R1
2
e
b
R
R
1
FIGURE 8 MODE 1a
2
e
FIGURE 7 MODE 1
f
O
9
Q
BW
Circuit dynamics
MODE 1a Non-Inverting BP LP (See Figure 8 )
f
Q
H
H
H
Circuit Dynamics H
Note V
O
OLP
OBP 1
OBP 2
e
e
e
e
e
e b
e b
e
IN
H
H
should be driven from a low impedance (
f
R3
R2
BW
quality factor of the complex pole pair
the
1 (Non-Inverting)
100
CLK
f
OLP
OLP(peak)
O
R3
R2
1 H
b
e
e
e
or
3 dB bandwidth of the bandpass output
OLP(peak)
R3
R2
H
H
f
CLK
50
OBP
ON c
Q
OBP1
j Q
or H
Q
c
j Q
e
OBP
H
Q
OLP
c
e
H
(for high Q’s)
TL H 10399 – 17
H
OLP
TL H 10399 – 16
OLP c
(for high Q’s)
k
1 k ) source
Q