LTC1563-2/LTC1563-3
Active RC, 4th Order
Lowpass Filter Family
FEATURES
■
■
DESCRIPTIO
■
■
■
■
■
■
■
■
■
■
Extremely Easy to Use—A Single Resistor Value
Sets the Cutoff Frequency (256Hz < f
C
< 256kHz)
Extremely Flexible—Different Resistor Values
Allow Arbitrary Transfer Functions with or without
Gain (256Hz < f
C
< 256kHz)
Supports Cutoff Frequencies Up to 360kHz Using
FilterCAD
TM
LTC1563-2: Unity-Gain Butterworth Response Uses a
Single Resistor Value, Different Resistor Values
Allow Other Responses with or without Gain
LTC1563-3: Unity-Gain Bessel Response Uses a
Single Resistor Value, Different Resistor Values
Allow Other Responses with or without Gain
Rail-to-Rail Input and Output Voltages
Operates from a Single 3V (2.7V Min) to
±5V
Supply
Low Noise: 36µV
RMS
for f
C
= 25.6kHz, 60µV
RMS
for
f
C
= 256kHz
f
C
Accuracy <
±2%
(Typ)
DC Offset < 1mV
Cascadable to Form 8th Order Lowpass Filters
Available in Narrow SSOP-16 Package
The LTC
®
1563-2/LTC1563-3 are a family of extremely
easy-to-use, active RC lowpass filters with rail-to-rail
inputs and outputs and low DC offset suitable for systems
with a resolution of up to 16 bits. The LTC1563-2, with a
single resistor value, gives a unity-gain Butterworth
response. The LTC1563-3, with a single resistor value,
gives a unity-gain Bessel response. The proprietary
architecture of these parts allows for a simple resistor
calculation:
R = 10k (256kHz/f
C
); f
C
= Cutoff Frequency
where f
C
is the desired cutoff frequency. For many appli-
cations, this formula is all that is needed to design a filter.
By simply utilizing different valued resistors, gain and
other responses are achieved.
The LTC1563-X features a low power mode, for the lower
frequency applications, where the supply current is re-
duced by an order of magnitude and a near zero power
shutdown mode.
The LTC1563-Xs are available in the narrow SSOP-16
package (Same footprint as an SO-8 package).
, LTC and LT are registered trademarks of Linear Technology Corporation.
FilterCAD is trademark of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
APPLICATIO S
■
■
■
■
■
Discrete RC Active Filter Replacement
Antialiasing Filters
Smoothing or Reconstruction Filters
Linear Phase Filtering for Data Communication
Phase Locked Loops
TYPICAL APPLICATIO
3.3V
0.1µF
LTC1563-2
1
2
3
R
R
R
V
IN
0.1µF
4
5
6
7
8
LP
SA
NC
INVA
NC
LPA
AGND
V
–
Single 3.3V, 256Hz to 256kHz Butterworth Lowpass Filter
V
+
LPB
NC
INVB
NC
SB
NC
EN
16
15
14
13
12
11
10
9
R
R
R
V
OUT
GAIN (dB)
10
0
–10
–20
–30
–40
–50
–60
–70
–80
100
1k
100k
10k
FREQUENCY (Hz)
1M
1563 TA02
10k
f
C
= 256kHz
R
( )
1563 TA01
U
Frequency Response
R = 10k
f
C
= 256kHz
R = 10M
f
C
= 256Hz
U
U
156323fa
1
LTC1563-2/LTC1563-3
ABSOLUTE
MAXIMUM
RATINGS
(Note 1)
PACKAGE/ORDER INFORMATION
TOP VIEW
LP 1
SA 2
NC 3
INVA 4
NC 5
LPA 6
AGND 7
V
–
8
16 V
+
15 LPB
14 NC
13 INVB
12 NC
11 SB
10 NC
9
EN
Total Supply Voltage (V
+
to V
–
) ............................... 11V
Maximum Input Voltage at
Any Pin ....................... (V
–
– 0.3V)
≤
V
PIN
≤
(V
+
+ 0.3V)
Power Dissipation .............................................. 500mW
Operating Temperature Range
LTC1563C ............................................... 0°C to 70°C
LTC1563I ............................................ – 40°C to 85°C
Storage Temperature Range ................. – 65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
ORDER PART
NUMBER
LTC1563-2CGN
LTC1563-3CGN
LTC1563-2IGN
LTC1563-3IGN
GN PART
MARKING
15632
15633
15632I
15633I
GN PACKAGE
16-LEAD PLASTIC SSOP
T
JMAX
= 150°C,
θ
JA
= 135°C/ W
NOTE: PINS LABELED NC ARE NOT CONNECTED
INTERNALLY AND SHOULD BE CONNECTED TO THE
SYSTEM GROUND
Order Options
Tape and Reel: Add #TR
Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF
Lead Free Part Marking:
http://www.linear.com/leadfree/
Consult LTC Marketing for Military grade parts.
ELECTRICAL CHARACTERISTICS
The
●
denotes specifications which apply over the full operating temperature range, otherwise specifications are TA = 25°C.
V
S
= Single 4.75V, EN pin to logic “low,” Gain = 1, R
FIL
= R11 = R21 = R31 = R12 = R22 = R32, specifications apply to both the high
speed (HS) and low power (LP) modes unless otherwise noted.
PARAMETER
CONDITIONS
Specifications for Both LTC1563-2 and LTC1563-3
Total Supply Voltage (V
S
), HS Mode
Total Supply Voltage (V
S
), LP Mode
Output Voltage Swing High (LPB Pin)
HS Mode
Output Voltage Swing Low (LPB Pin)
HS Mode
Output Swing High (LPB Pin)
LP Mode
Output Swing Low (LPB Pin)
LP Mode
DC Offset Voltage, HS Mode
(Section A Only)
DC Offset Voltage, LP Mode
(Section A Only)
DC Offset Voltage, HS Mode
(Input to Output, Sections A, B Cascaded)
V
S
= 3V, f
C
= 25.6kHz, R
FIL
= 100k, R
L
= 10k to GND
V
S
= 4.75V, f
C
= 25.6kHz, R
FIL
= 100k, R
L
= 10k to GND
V
S
=
±5V,
f
C
= 25.6kHz, R
FIL
= 100k, R
L
= 10k to GND
V
S
= 3V, f
C
= 25.6kHz, R
FIL
= 100k, R
L
= 10k to GND
V
S
= 4.75V, f
C
= 25.6kHz, R
FIL
= 100k, R
L
= 10k to GND
V
S
=
±5V,
f
C
= 25.6kHz, R
FIL
= 100k, R
L
= 10k to GND
V
S
= 2.7V, f
C
= 25.6kHz, R
FIL
= 100k, R
L
= 10k to GND
V
S
= 4.75V, f
C
= 25.6kHz, R
FIL
= 100k, R
L
= 10k to GND
V
S
=
±5V,
f
C
= 25.6kHz, R
FIL
= 100k, R
L
= 10k to GND
V
S
= 2.7V, f
C
= 25.6kHz, R
FIL
= 100k, R
L
= 10k to GND
V
S
= 4.75V, f
C
= 25.6kHz, R
FIL
= 100k, R
L
= 10k to GND
V
S
=
±5V,
f
C
= 25.6kHz, R
FIL
= 100k, R
L
= 10k to GND
V
S
= 3V, f
C
= 25.6kHz, R
FIL
= 100k
V
S
= 4.75V, f
C
= 25.6kHz, R
FIL
= 100k
V
S
=
±5V,
f
C
= 25.6kHz, R
FIL
= 100k
V
S
= 2.7V, f
C
= 25.6kHz, R
FIL
= 100k
V
S
= 4.75V, f
C
= 25.6kHz, R
FIL
= 100k
V
S
=
±5V,
f
C
= 25.6kHz, R
FIL
= 100k
V
S
= 3V, f
C
= 25.6kHz, R
FIL
= 100k
V
S
= 4.75V, f
C
= 25.6kHz, R
FIL
= 100k
V
S
=
±5V,
f
C
= 25.6kHz, R
FIL
= 100k
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
MIN
3
2.7
2.9
4.55
4.8
TYP
MAX
11
11
UNITS
V
V
V
V
V
2.95
4.7
4.9
0.015
0.02
– 4.95
0.05
0.05
– 4.9
2.6
4.55
4.8
2.65
4.65
4.9
0.01
0.015
– 4.95
±1.5
±1.0
±1.5
±2
±2
±2
±1.5
±1.0
±1.5
0.05
0.05
– 4.9
±3
±3
±3
±6
±6
±7
±3
±3
±3
156323fa
2
U
W
U
U
W W
W
V
V
V
V
V
V
V
V
V
mV
mV
mV
mV
mV
mV
mV
mV
mV
LTC1563-2/LTC1563-3
ELECTRICAL CHARACTERISTICS
The
●
denotes specifications which apply over the full operating temperature range, otherwise specifications are TA = 25°C.
V
S
= Single 4.75V, EN pin to logic “low,” Gain = 1, R
FIL
= R11 = R21 = R31 = R12 = R22 = R32, specifications apply to both the high
speed (HS) and low power (LP) modes unless otherwise noted.
PARAMETER
DC Offset Voltage, LP Mode
(Input to Output, Sections A, B Cascaded)
DC Offset Voltage Drift, HS Mode
(Input to Output, Sections A, B Cascaded)
DC Offset Voltage Drift, LP Mode
(Input to Output, Sections A, B Cascaded)
AGND Voltage
Power Supply Current, HS Mode
CONDITIONS
V
S
= 2.7V, f
C
= 25.6kHz, R
FIL
= 100k
V
S
= 4.75V, f
C
= 25.6kHz, R
FIL
= 100k
V
S
=
±5V,
f
C
= 25.6kHz, R
FIL
= 100k
V
S
= 3V, f
C
= 25.6kHz, R
FIL
= 100k
V
S
= 4.75V, f
C
= 25.6kHz, R
FIL
= 100k
V
S
=
±5V,
f
C
= 25.6kHz, R
FIL
= 100k
V
S
= 2.7V, f
C
= 25.6kHz, R
FIL
= 100k
V
S
= 4.75V, f
C
= 25.6kHz, R
FIL
= 100k
V
S
=
±5V,
f
C
= 25.6kHz, R
FIL
= 100k
V
S
= 4.75V, f
C
= 25.6kHz, R
FIL
= 100k
V
S
= 3V, f
C
= 25.6kHz, R
FIL
= 100k
V
S
= 4.75V, f
C
= 25.6kHz, R
FIL
= 100k
V
S
=
±5V,
f
C
= 25.6kHz, R
FIL
= 100k
V
S
= 2.7V, f
C
= 25.6kHz, R
FIL
= 100k
V
S
= 4.75V, f
C
= 25.6kHz, R
FIL
= 100k
V
S
=
±5V,
f
C
= 25.6kHz, R
FIL
= 100k
V
S
= 4.75V, f
C
= 25.6kHz, R
FIL
= 100k
V
S
= 3V
V
S
= 4.75V
V
S
=
±5V
V
S
= 3V
V
S
= 4.75V
V
S
=
±5V
V
S
= 3V
V
S
= 4.75V
V
S
=
±5V
V
S
= 3V
V
S
= 4.75V
V
S
=
±5V
V
S
= 3V
V
S
= 4.75V
V
S
=
±5V
V
S
= 2.7V
V
S
= 4.75V
V
S
=
±5V
V
S
= 3V, R
FIL
= 100k
V
S
= 4.75V, R
FIL
= 100k
V
S
=
±5V,
R
FIL
= 100k
V
S
= 3V, R
FIL
= 10k
V
S
= 4.75V, R
FIL
= 10k
V
S
=
±5V,
R
FIL
= 10k
V
S
= 2.7V, R
FIL
= 100k
V
S
= 4.75V, R
FIL
= 100k
V
S
=
±5V,
R
FIL
= 100k
(Note 3)
MIN
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
TYP
±2
±2
±2
10
10
10
10
10
10
MAX
±7
±7
±8
UNITS
mV
mV
mV
µV/°C
µV/°C
µV/°C
µV/°C
µV/°C
µV/°C
2.35
2.375
8.0
10.5
15
1.0
1.4
2.3
1
2.40
14
17
23
1.8
2.5
3.5
20
0.8
1
1
V
mA
mA
mA
mA
mA
mA
µA
V
V
V
V
V
V
Power Supply Current, LP Mode
Shutdown Mode Supply Current
EN Input
Logic Low Level
EN Input
Logic High Level
LP
Logic Low Level
LP
Logic High Level
LTC1563-2 Transfer Function Characteristics
Cutoff Frequency Range, f
C
HS Mode
(Note 2)
Cutoff Frequency Range, f
C
LP Mode
(Note 2)
Cutoff Frequency Accuracy, HS Mode
f
C
= 25.6kHz
Cutoff Frequency Accuracy, HS Mode
f
C
= 256kHz
Cutoff Frequency Accuracy, LP Mode
f
C
= 25.6kHz
Cutoff Frequency Temperature Coefficient
2.5
4.3
4.4
0.8
1
1
2.5
4.3
4.4
0.256
0.256
0.256
0.256
0.256
0.256
–2.0
–2.0
–2.0
–5
–5
–5
–3
–3
–3
±1.5
±1.5
±1.5
±1.5
±1.5
±1.5
±1.5
±1.5
±1.5
±1
256
256
256
25.6
25.6
25.6
3.5
3.5
3.5
2.5
2.5
2.5
3
3
3
V
V
V
V
V
V
kHz
kHz
kHz
kHz
kHz
kHz
%
%
%
%
%
%
%
%
%
ppm/°C
156323fa
3
LTC1563-2/LTC1563-3
ELECTRICAL CHARACTERISTICS
The
●
denotes specifications which apply over the full operating temperature range, otherwise specifications are TA = 25°C.
V
S
= Single 4.75V, EN pin to logic “low,” Gain = 1, R
FIL
= R11 = R21 = R31 = R12 = R22 = R32, specifications apply to both the high
speed (HS) and low power (LP) modes unless otherwise noted.
PARAMETER
Passband Gain, HS Mode, f
C
= 25.6kHz
V
S
= 4.75V, R
FIL
= 100k
Stopband Gain, HS Mode, f
C
= 25.6kHz
V
S
= 4.75V, R
FIL
= 100k
Passband Gain, HS Mode, f
C
= 256kHz
V
S
= 4.75V, R
FIL
= 10k
Stopband Gain, HS Mode, f
C
= 256kHz
V
S
= 4.75V, R
FIL
= 10k
Passband Gain, LP Mode, f
C
= 25.6kHz
V
S
= 4.75V, R
FIL
= 100k
Stopband Gain, LP Mode, f
C
= 25.6kHz
V
S
= 4.75V, R
FIL
= 100k
LTC1563-3 Transfer Function Characteristics
Cutoff Frequency Range, f
C
HS Mode
(Note 2)
Cutoff Frequency Range, f
C
LP Mode
(Note 2)
Cutoff Frequency Accuracy, HS Mode
f
C
= 25.6kHz
Cutoff Frequency Accuracy, HS Mode
f
C
= 256kHz
Cutoff Frequency Accuracy, LP Mode
f
C
= 25.6kHz
Cutoff Frequency Temperature Coefficient
Passband Gain, HS Mode, f
C
= 25.6kHz
V
S
= 4.75V, R
FIL
= 100k
Stopband Gain, HS Mode, f
C
= 25.6kHz
V
S
= 4.75V, R
FIL
= 100k
Passband Gain, HS Mode, f
C
= 256kHz
V
S
= 4.75V, R
FIL
= 10k
Stopband Gain, HS Mode, f
C
= 256kHz
V
S
= 4.75V, R
FIL
= 10k
Passband Gain, LP Mode, f
C
= 25.6kHz
V
S
= 4.75V, R
FIL
= 100k
Stopband Gain, LP Mode, f
C
= 25.6kHz
V
S
= 4.75V, R
FIL
= 100k
V
S
= 3V
V
S
= 4.75V
V
S
=
±5V
V
S
= 2.7V
V
S
= 4.75V
V
S
=
±5V
V
S
= 3V, R
FIL
= 100k
V
S
= 4.75V, R
FIL
= 100k
V
S
=
±5V,
R
FIL
= 100k
V
S
= 3V, R
FIL
= 10k
V
S
= 4.75V, R
FIL
= 10k
V
S
=
±5V,
R
FIL
= 10k
V
S
= 2.7V, R
FIL
= 100k
V
S
= 4.75V, R
FIL
= 100k
V
S
=
±5V,
R
FIL
= 100k
(Note 3)
Test Frequency = 2.56kHz (0.1 • f
C
)
Test Frequency = 12.8kHz (0.5 • f
C
)
Test Frequency = 51.2kHz (2 • f
C
)
Test Frequency = 102.4kHz (4 • f
C
)
Test Frequency = 25.6kHz (0.1 • f
C
)
Test Frequency = 128kHz (0.5 • f
C
)
Test Frequency = 400kHz (1.56 • f
C
)
Test Frequency = 500kHz (1.95 • f
C
)
Test Frequency = 2.56kHz (0.1 • f
C
)
Test Frequency = 12.8kHz (0.5 • f
C
)
Test Frequency = 51.2kHz (2 • f
C
)
Test Frequency = 102.4kHz (4 • f
C
)
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
CONDITIONS
Test Frequency = 2.56kHz (0.1 • f
C
)
Test Frequency = 12.8kHz (0.5 • f
C
)
Test Frequency = 51.2kHz (2 • f
C
)
Test Frequency = 102.4kHz (4 • f
C
)
Test Frequency = 25.6kHz (0.1 • f
C
)
Test Frequency = 128kHz (0.5 • f
C
)
Test Frequency = 400kHz (1.56 • f
C
)
Test Frequency = 500kHz (1.95 • f
C
)
Test Frequency = 2.56kHz (0.1 • f
C
)
Test Frequency = 12.8kHz (0.5 • f
C
)
Test Frequency = 51.2kHz (2 • f
C
)
Test Frequency = 102.4kHz (4 • f
C
)
●
●
●
●
●
●
●
●
●
●
●
●
MIN
– 0.2
– 0.3
TYP
0
0
– 24
– 48
MAX
0.2
0.3
– 21.5
– 46
0.2
0.5
–13.5
– 21.5
0.25
0.6
– 22
– 46.5
256
256
256
25.6
25.6
25.6
UNITS
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
kHz
kHz
kHz
kHz
kHz
kHz
%
%
%
%
%
%
%
%
%
ppm/°C
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
– 0.2
– 0.5
0
0
– 15.7
– 23.3
– 0.25
– 0.6
0
– 0.02
– 24
– 48
0.256
0.256
0.256
0.256
0.256
0.256
–3
–3
–3
–3
–3
–3
–4
–4
–4
– 0.2
–1.0
±2
±2
±2
±2
±2
±2
±3
±3
±3
±1
– 0.03
– 0.72
–13.6
– 34.7
– 0.2
–1.1
– 0.03
– 0.72
– 8.3
– 13
– 0.2
–1.0
– 0.03
– 0.72
– 13.6
– 34.7
5.5
5.5
5.5
6
6
6
7
7
7
0.2
– 0.25
–10
– 31
0.2
– 0.5
–6
–10.5
0.2
– 0.25
–11
– 32
Note 1:
Absolute Maximum Ratings are those value beyond which the life
of a device may be impaired.
Note 2:
The minimum cutoff frequency of the LTC1563 is arbitrarily listed
as 256Hz. The limit is arrived at by setting the maximum resistor value
limit at 10MΩ. The LTC1563 can be used with even larger valued resistors.
When using very large values of resistance careful layout and thorough
assembly practices are required. There may also be greater DC offset at
high temperatures when using such large valued resistors.
Note 3:
The cutoff frequency temperature drift at low frequencies is as
listed. At higher cutoff frequencies (approaching 25.6kHz in low power
mode and approaching 256kHz in high speed mode) the internal
amplifier’s bandwidth can effect the cutoff frequency. At these limits the
cutoff frequency temperature drift is
±15ppm/°C.
156323fa
4
LTC1563-2/LTC1563-3
TYPICAL PERFOR A CE CHARACTERISTICS
Output Voltage Swing High vs
Load Resistance
3.4
V
S
= SINGLE 3.3V
3.2
5.0
5.5
V
S
= SINGLE 5V
5.0
OUTPUT VOLTAGE (V)
OUTPUT VOLTAGE (V)
3.0
2.8
HS MODE
2.6
LP MODE
2.4
2.2
2.0
100
1k
10k
100k
LOAD RESISTANCE—LOAD TO GROUND (Ω)
1563 G01
4.5
HS MODE
4.0
LP MODE
3.5
3.0
2.5
100
1k
10k
100k
LOAD RESISTANCE—LOAD TO GROUND (Ω)
1563 G02
OUTPUT VOLTAGE (V)
Output Voltage Swing Low vs
Load Resistance
0.025
V
S
= SINGLE 3.3V
0.020
OUTPUT VOLTAGE (V)
HS MODE
OUTPUT VOLTAGE (V)
OUTPUT VOLTAGE (V)
0.015
LP MODE
0.010
0.005
0
1k
10k
100k
100
LOAD RESISTANCE—LOAD TO GROUND (Ω)
1563 G04
THD + Noise vs Input Voltage
–40
3.3V SUPPLY
–50
–50
–40
(THD + NOISE)/SIGNAL (dB)
(THD + NOISE)/SIGNAL (dB)
5V SUPPLY
–60
±5V
SUPPLY
–70
–80
–90
f
C
= 25.6kHz
LOW POWER MODE
f
IN
= 5kHz
0.1
1
INPUT VOLTAGE (V
P-P
)
10
1563 G07
5V SUPPLY
–60
±5V
SUPPLY
–70
–80
–90
f
C
= 25.6kHz
HIGH SPEED MODE
f
IN
= 5kHz
0.1
1
INPUT VOLTAGE (V
P-P
)
10
1563 G08
(THD + NOISE)/SIGNAL (dB)
–100
U W
Output Voltage Swing High vs
Load Resistance
5.5
Output Voltage Swing High vs
Load Resistance
V
S
=
±5V
4.5
HS MODE
4.0
LP MODE
3.5
3.0
2.5
100
1k
10k
100k
LOAD RESISTANCE—LOAD TO GROUND (Ω)
1563 G03
Output Voltage Swing Low vs
Load Resistance
0.025
V
S
= SINGLE 5V
0.020
–4.5
–4.6
–4.7
LP MODE
HS MODE
–4.3
Output Voltage Swing Low vs
Load Resistance
V
S
=
±
5V
–4.4
0.015
0.010
HS MODE
–4.8
–4.9
LP MODE
0.005
0
1k
10k
100k
100
LOAD RESISTANCE—LOAD TO GROUND (Ω)
1563 G05
–5.0
100
1k
10k
100k
LOAD RESISTANCE—LOAD TO GROUND (Ω)
1563 G06
THD + Noise vs Input Voltage
–40
3.3V SUPPLY
–50
THD + Noise vs Input Voltage
3.3V SUPPLY
5V SUPPLY
–60
±5V
SUPPLY
–70
–80
–90
–100
f
C
= 256kHz
HIGH SPEED MODE
f
IN
= 50kHz
0.1
1
INPUT VOLTAGE (V
P-P
)
10
1563 G09
–100
156323fa
5