LTC1064 Low Noise, Fast, Quad Universal Filter Building Block
FEATURES
■ ■ ■ ■ ■ ■ ■ ■ ■ ■
DESCRIPTIO
Four Filters in a 0.3 Inch Wide Package Maximum Center Frequency: 140kHz Customized Version with Internal Resistors Available One Half the Noise of the LTC1059/LTC1060/ LTC1061 Devices Maximum Clock Frequency: 7MHz Clock-to-Center Frequency Ratio of 50:1 and 100:1 Simultaneously Available Power Supplies: ±2.375V to ±8V Low Offsets Low Harmonic Distortion Available in 24-Pin DIP and SO Wide Packages
The LTC®1064 consists of four high speed, low noise switched-capacitor filter building blocks. Each filter building block, together with an external clock and three to five resistors can provide various 2nd order functions like lowpass, highpass, bandpass and notch. The center frequency of each 2nd order function can be tuned with an external clock, or a clock and resistor ratio. For Q ≤ 5, the center frequency range is from 0.1Hz to 100kHz. For Q ≤ 3, the center frequency range can be extended to 140kHz. Up to 8th order filters can be realized by cascading all four 2nd order sections. Any classical filter realization (such as Butterworth, Cauer, Bessel and Chebyshev) can be formed. A customized monolithic version of the LTC1064 including internal thin film resistors can be obtained for high volume applications. Consult LTC Marketing for details.
, LTC and LT are registered trademarks of Linear Technology Corporation. LTCMOS is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners.
APPLICATIO S
■ ■ ■ ■
Anti-Aliasing Filters Wide Frequency Range Tracking Filters Spectral Analysis Loop Filters
TYPICAL APPLICATIO
Clock-Tunable 8th Order Cauer Lowpass Filter with fCUTOFF up to 100kHz
13k 66.5k 22.1k VIN 10k 18.25k 10.7k 1 2 3 4 5 6 8V 7 0.1µF 10k 49.9K 11.5K (FROM RH2, RL2) 8 9 10 11 12 24 23 22 21 20 –8V 10k 12.1k 17.4k RL2 26.7k RH2 102k PIN 12
INV B HPB/NB BPB LPB SB AGND V+ SA LPA BPA HPA/NA INV A LTC1064
INV C HPC/NC BPC LPC SC V
–15 –30
GAIN (dB)
–45 –60 –75 –90
– 19
CLK
18 17 16 15 14 13
5MHz 8V 41.2k 12.7k 14k 121k 10k
0.1µF
50/100 LPD BPD HPD INV D
VOUT
–105 –120 –135 1k 10k 100k INPUT FREQUENCY (Hz) 1M
1064 TA02
FOR fCLK = 5MHz, ADD C1 = 10pF BETWEEN PINS 4, 1 C2 = 10pF BETWEEN PINS 21, 24 C3 = 27pF BETWEEN PINS 9, 12
WIDEBAND NOISE ≅ 140µVRMS
1064 TA01
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Gain vs Frequency
0 fCLK = 5MHz RIPPLE = ±0.1dB fCLK = 1MHz RIPPLE = ±0.05dB
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LTC1064
ABSOLUTE
AXI U RATI GS (Note 1)
Storage Temperature Range ................ – 65°C to 150°C Lead Temperature (Soldering, 10 sec)................. 300°C
Total Supply Voltage (V + to V –) ............................. 16V Power Dissipation ............................................. 500mW Operating Temperature Range LTC1064AC/LTC1064C .................... – 40°C to 85°C LTC1064AM LTC1064M (OBSOLETE) ............... – 55°C to 125°C
PACKAGE/ORDER I FOR ATIO
TOP VIEW INV B HPB/NB BPB LPB SB AGND V+ SA LPA 1 2 3 4 5 6 7 8 9 24 INV C 23 HPC/NC 22 BPC 21 LPC 20 SC 19 V – 18 CLK 17 50/100 16 LPD 15 BPD 14 HPD 13 INV D
ORDER PART NUMBER LTC1064ACN LTC1064CN
BPA 10 HPA/NA 11 INV A 12
N PACKAGE 24-LEAD PLASTIC DIP TJMAX = 110°C, θJA = 65°C/W
J PACKAGE 24-LEAD CERAMIC DIP TJMAX = 150°C, θJA = 100°C/W
LTC1064ACJ LTC1064CJ LTC1064AMJ LTC1064MJ
OBSOLETE PACKAGE
Consider the 24-Lead N Package as an Alternate Source
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 parts specified with wider operating temperature ranges.
(Internal Op Amps) The ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C.
PARAMETER Operating Supply Voltage Range Voltage Swings Output Short-Circuit Current (Source/Sink) DC Open-Loop Gain GBW Product Slew Rate CONDITIONS VS = ± 5V, RL = 5k
●
ELECTRICAL CHARACTERISTICS
VS = ± 5V VS = ± 5V, RL = 5k VS = ± 5V VS = ± 5V
2
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TOP VIEW INV B HPB/NB BPB LPB SB AGND V+ SA LPA 1 2 3 4 5 6 7 8 9 24 INV C 23 HPC/NC 22 BPC 21 LPC 20 SC 19 V – 18 CLK 17 50/100 16 LPD 15 BPD 14 HPD 13 INV D
ORDER PART NUMBER LTC1064CSW
BPA 10 HPA/NA 11 INV A 12
SW PACKAGE 24-LEAD PLASTIC SO WIDE TJMAX = 100°C, θJA = 85°C/ W
MIN ± 2.375 ± 3.2 ± 3.1
TYP ± 3.6 3 80 7 10
MAX ±8
UNITS V V V mA dB MHz V/µs
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LTC1064
(Complete Filter) The ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at VS = ± 5V, TA = 25°C, TTL clock input level, unless otherwise specified.
PARAMETER Center Frequency Range, fO Input Frequency Range Clock-to-Center Frequency Ratio, fCLK /fO CONDITIONS VS = ± 8V, Q ≤ 3 LTC1064 LTC1064A (Note 2) fCLK = 1MHz, fO = 20kHz, Pin 17 High Sides A, B, C: Mode 1, R1 = R3 = 5k, R2 = 5k, Q = 10, Sides D: Mode 3, R1 = R3 = 50k R2 = R4 = 5k Same as Above, Pin 17 Low, fCLK = 1MHz fO = 10kHz Sides A, B, C Side D fCLK = 1MHz fCLK = 4MHz, fO = 80kHz, Pin 17 High Sides A, B, C: Mode 1, VS = ±7.5V R1 = R3 = 50k, R2 = 5k, Q = 5 Side D: Mode 3, R1 = R3 = 50k R2 = R4 = 5k, fCLK = 4MHz Same as Above, Pin 17 Low fCLK = 4MHz, fO = 40kHz Sides A, B, C: Mode 1, Q = 10 Side D: Mode 3, fCLK = 1MHz Mode 1, 50:1, fCLK < 2MHz Mode 1, 100:1, fCLK < 2MHz Mode 3, fCLK < 2MHz fCLK = 1MHz, 50:1 or 100:1 fCLK = 1MHz, 50:1 or 100:1 fCLK = 1MHz, 50:1 or 100:1 fCLK < 1MHz Mode 1, Q < 5, VS ≥ ± 5V MIN TYP 0.1 to 140 0 to 1 50 ± 0.3 MAX UNITS kHz MHz % % % % 100 ± 0.8 100 ± 0.9 0.4
●
ELECTRICAL CHARACTERISTICS
● ●
50 ± 0.8 50 ± 0.9
LTC1064 LTC1064A (Note 2)
100 ± 0.3
● ●
% % % % %
Clock-to-Center Frequency Ratio, Side-to-Side Matching Clock-to-Center Frequency Ratio, fCLK/fO (Note 3)
LTC1064 LTC1064A (Note 2) LTC1064 LTC1064A (Note 2)
1 50 ± 0.6 50 ± 1.3
LTC1064 LTC1064 A (Note 2) Q Accuracy fO Temperature Coefficient Q Temperature Coefficient DC Offset Voltage VOS1 (Table 1) VOS2 (Table 1) VOS3 (Table 1)
100 ± 0.6
● ●
● ● ●
Clock Feedthrough Maximum Clock Frequency Power Supply Current
9
●
±2 ±3 ±1 ±5 ±5 2 3 3 0.2 7 12
100 ± 1.3 6 8
15 45 45
23 26
% % % % ppm/°C ppm/°C ppm/°C mV mV mV mVRMS MHz mA mA
Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired.
Note 2: Contact LTC Marketing. Note 3: Not tested, guaranteed by design.
Table 1. Output DC Offsets, One 2nd Order Section
MODE 1 1b 2 3 VOSN PINS 2, 11, 14, 23 VOS1 [(1/Q) + 1 + ⏐ HOLP⏐ ] – VOS3 /Q ⏐ ⏐ VOS1 [(1/Q) + 1 + (R2/R1)] – VOS3 /Q VOS1 [(1 + (R2/R1) + (R2/R3) + (R2/R4) – VOS3 (R2/R3)] × [ R4/(R2 + R4)] + VOS2[R2/(R2 + R4)] VOS2 VOSBP PINS 3, 10, 15, 22 VOS3 VOS3 VOS3 VOS3 VOSLP PINS 4, 9, 16, 21 VOSN – VOS2 ~(VOSN – VOS2)[1 + (R5/R6)] VOSN – VOS2 VOS1[1 + (R4/R1) + (R4/R2) + (R4/R3)] – VOS2(R4/R2) – VOS3(R4/R3)
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LTC1064
BLOCK DIAGRA
INV A (12) AGND (6)
INV B (1)
INV C (24)
INV D (13)
TYPICAL PERFORMANCE CHARACTERISTICS
Mode 1, (fCLK /fO) = 50:1
20 TA = 25°C Q=5 Q = 10
Q ERROR (%)
Q ERROR (%)
Q ERROR (%)
15 10 5 0 –5 TA = 25°C Q = 5 OR 10 VS = ± 2.5V
VS = ± 5V VS = ± 7.5V
CENTER FREQUENCY ERROR (%)
CENTER FREQUENCY ERROR (%)
1.5 1.0 0.5 0 VS = ± 2.5V
VS = ±5V
1.5 0.5 0
VS = ±5V
CENTER FREQUENCY ERROR (%)
0 10 20 30 40 50 60 70 80 90 100110 120 CENTER FREQUENCY (kHz)
1064 G01
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UW
W
HPA/NA (11) BPA (10) LPA (9) V + (7)
– +
HPB/NB (2)
+
Σ
–
+∫
BPB (3)
+∫
LPB (4)
50/100 (17) CLK (18) V – (19)
– +
HPC/NC (23)
SA (8)
+
Σ
–
SB (5)
+∫
BPC (22)
+∫
LPC (21) BY TYING PIN 17 TO V +, ALL SECTIONS OPERATE WITH (fCLK/fO) = 50:1 BY TYING PIN 17 TO V –, ALL SECTIONS OPERATE WITH (fCLK/fO) = 100:1 LPD (16) BY TYING PIN 17 TO AGND, SECTIONS B, C OPERATE WITH (fCLK/fO) = 50:1 AND SECTIONS A, D OPERATE AT 100:1
– +
HPD (14)
+
Σ
–
SC (20)
+∫
BPD (15)
+∫
– +
+∫ +∫
1064 BD
Mode 1, (fCLK /fO) = 100:1
20 15 10 5 0 –5
VS = ± 7.5V
Mode 2, (fCLK /fO) = 25:1
20 15 10 5 0 –5 1.5 1.0 0.5 0 0 10 20 30 40 50 60 70 80 90 100110 120 CENTER FREQUENCY (kHz)
1064 G03
TA = 25°C Q=5 Q = 10 VS = ± 5V VS = ± 7.5V
TA = 25°C Q = 10 PIN 17 AT V + (R2/R4) = 3 VS = ± 2.5V CC = 15pF VS = ±5V CC = 15pF
VS = ± 2.5V
TA = 25°C Q = 5 OR 10
1.0 VS = ± 2.5V
VS = ± 7.5V
VS = ± 2.5V
VS = ±5V
0 10 20 30 40 50 60 70 80 90 100110 120 CENTER FREQUENCY (kHz)
1064 G02
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LTC1064 TYPICAL PERFORMANCE CHARACTERISTICS
Mode 2, (fCLK /fO) = 25:1
20 TA = 25°C VS = ± 7.5V PIN 17 AT V + (R2/R4) = 3 Q=5 CC = 22pF Q=2 CC = 39pF
Q ERROR (%)
Q ERROR (%)
15 10 5 0 –5
Q ERROR (%)
CENTER FREQUENCY ERROR (%)
1.0 0.5 0
Q=5
Q=2
1.0 0.5 0
CENTER FREQUENCY ERROR (%)
1.5
CENTER FREQUENCY ERROR (%)
0 20 40 60 80 100 120140160180 200 CENTER FREQUENCY (kHz)
1064 G04
Mode 3, (fCLK /fO) = 50:1
20 Q ERROR (%) 15 10 5 0 –5 CENTER FREQUENCY ERROR (%) 1.5 1.0 0.5 0 0 10 20 30 40 50 60 70 80 90 100 110 120 CENTER FREQUENCY (kHz)
1064 G07
Q ERROR (%)
15 10 5 0 –5
VS = ± 5V VS = ± 7.5V VS = ± 5V VS = ± 7.5V
WIDEBAND NOISE (µV/RMS)
TA = 25°C CC = 15pF R2 = R4 VS = ± 7.5V Q=2 Q=1
VS = ± 7.5V VS = ± 2.5V VS = ±5V
CENTER FREQUENCY ERROR (%)
Power Supply Current vs Supply Voltage
48 44
POWER SUPPLY CURRENT (mA)
40 36 32 28 24 20 16 12 8 4 0 0 2 4 6 8 10 12 14 16 18 20 22 24 POWER SUPPLY VOLTAGE (V + – V –)
1064 G10
1064 G11
UW
Mode 2, (fCLK /fO) = 50:1
20 15 10 5 0 –5 1.5 VS = ±5V VS = ± 2.5V VS = ± 7.5V VS = ± 2.5V VS = ± 5V VS = ± 7.5V TA = 25°C PIN 17 AT V – (R2/R4) = 3 Q=5 Q = 10
Mode 3, (fCLK /fO) = 50:1
TA = 25°C CC = 5pF R2 = R4 Q=5 Q = 10 VS = ± 7.5V
20 15 10 5 0 –5 1.5 1.0 0.5 0
VS = ± 5V VS = ± 2.5V
VS = ± 2.5V
VS = ±5V
VS = ± 7.5V
0 10 20 30 40 50 60 70 80 90 100110 120 CENTER FREQUENCY (kHz)
1064 G05
0 10 20 30 40 50 60 70 80 90 100110 120 CENTER FREQUENCY (kHz)
1064 G06
Mode 3, (fCLK /fO) = 100:1
240
Wideband Noise vs Q
TA = 25°C CC = 5pF R2 = R4 Q = 10
220 200 180 160 140 120 100 80 60 40 20 0 0 2 4 6 8 10 12 14 16 18 20 22 24 Q
1064 G09
20
VS = ± 2.5V
ANY OUTPUT R3 = R1 ONE SECOND ORDER SECTION MODE 1 OR 3 100:1 OR 50:1
± 7.5V ± 5V ±2.5V
VS = ± 2.5V 1.5 1.0 0.5 0
0 10 20 30 40 50 60 70 80 90 100110 120 CENTER FREQUENCY (kHz)
1064 G08
Harmonic Distortion, 8th Order LP Butterworth, fC = 20kHz, THD = 0.015% for 3VRMS Input
–55°C 25°C 125°C
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LTC1064
PIN FUNCTIONS
V +, V – (Pins 7, 19): Power Supplies. They should be bypassed with a 0.1µF ceramic capacitor. Low noise, nonswitching power supplies are recommended. The device operates with a single 5V supply and with dual supplies. The absolute maximum operating power supply voltage is ± 8V. CLK (Pin 18): Clock. For ± 5V supplies the logic threshold level is 1.4V. For ± 8V and 0V to 5V supplies the logic threshold levels are 2.2V and 3V respectively. The logic threshold levels vary ± 100mV over the full military temperature range. The recommended duty cycle of the input clock is 50%, although for clock frequencies below 500kHz, the clock “on” time can be as low as 200ns. The maximum clock frequency for ± 5V supplies is 4MHz. For ± 7V supplies and above, the maximum clock frequency is 7MHz. AGND (Pin 6): Analog Ground. When the LTC1064 operates with dual supplies, Pin 6 should be tied to system ground. When the LTC1064 operates with a single positive supply, the analog ground pin should be tied to 1/2 supply and it should be bypassed with a 1µF solid tantalum in parallel with a 0.1µF ceramic capacitor, Figure 1. The positive input of all the internal op amps, as well as the common reference of all the internal switches, are internally tied to the analog ground pin. Because of this, a very “clean” ground is recommended. 50/100 (Pin 17): By tying Pin 17 to V +, all filter sections operate with a clock-to-center frequency ratio internally set at 50:1. When Pin 17 is at mid-supplies, sections B and C operate with (fCLK /fO) = 50:1 and sections A and D operate at 100:1. When Pin 17 is shorted to the negative supply pin, all filter sections operate with (fCLK /fO) = 100:1.
NOTE: PINS 5, 8, 20, IF NOT USED, SHOULD BE CONNECTED TO PIN 6
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1 2 V+ 3 4 5k V+/2 1µF 5 6 7 5k 0.1µF 8 9 10 ANALOG GROUND PLANE 11 12 AGND V+ V– CLK 50/100 LTC1064
24 23 22 21 20 19 18 17 16 15 14 13 TO DIGITAL GROUND CLOCK INPUT V + = 15V, TRIP VOLTAGE = 7V V + = 10V, TRIP VOLTAGE = 6.4V V + = 5V, TRIP VOLTAGE = 3V
+
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Figure 1. Single Supply Operation
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LTC1064
APPLICATIONS INFORMATION
ANALOG CONSIDERATIONS Grounding and Bypassing The LTC1064 should be used with separated analog and digital ground planes and single point grounding techniques. Pin 6 (AGND) should be tied directly to the analog ground plane. Pin 7 (V +) should be bypassed to the ground plane with a 0.1µF ceramic capacitor with leads as short as possible. Pin 19 (V –) should be bypassed with a 0.1µF ceramic capacitor. For single supply applications, V – can be tied to the analog ground plane. For good noise performance, V + and V – must be free of noise and ripple. All analog inputs should be referenced directly to the single point ground. The clock inputs should be shielded from and/or routed away from the analog circuitry and a separate digital ground plane used. Figure 2 shows an example of an ideal ground plane design for a 2-sided board. Of course this much ground plane will not always be possible, but users should strive to get as close to this as possible. Protoboards are not recommended. Buffering the Filter Output When driving coaxial cables and 1× scope probes, the filter output should be buffered. This is important especially when high Qs are used to design a specific filter. Inadequate buffering may cause errors in noise, distortion, Q and gain measurements. When 10 × probes are used, buffering is usually not required. An inverting buffer is recommended especially when THD tests are performed. As shown in Figure 3, the buffer should be adequately bypassed to minimize clock feedthrough.
1 2 3 4 5 6 7.5V 7 8 0.1µF CERAMIC 9 10 ANALOG GROUND PLANE 11 12
PIN 1 IDENT
LTC1064
Figure 2. Example Ground Plane Breadboard Technique for LTC1064
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24 23 22 21 20 19 18 17 16 15 14 13 –7.5V 5k
VIN FOR BEST HIGH FREQUENCY RESPONSE PLACE RESISTORS PARALLEL TO DOUBLESIDED COPPER CLAD BOARD AND LAY FLAT (4 RESISTORS SHOWN HERE TYPICAL)
0.1µF CERAMIC
CLOCK DIGITAL GROUND PLANE (SINGLE POINT GROUND)
NOTE: CONNECT ANALOG AND DIGITAL GROUND PLANES AT A SINGLE POINT AT THE BOARD EDGE
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LTC1064
APPLICATIONS INFORMATION
Offset Nulling Lowpass filters may have too much DC offset for some users. A servo circuit may be used to actively null the offsets of the LTC1064 or any LTC switched-capacitor filter. The circuit shown in Figure 4 will null offsets to better than 300µV. This circuit takes seconds to settle because of the integrator pole frequency.
SEPARATE V + POWER SUPPLY TRACE FOR BUFFER R12 R11 VIN R21 R31 R22 R32 10k V TRACE FOR FILTER LTC1064 POSITIVE SUPPLY 0.1µF 7 19 0.1µF
+
Figure 3. Buffering the Output of a 4th Order Bandpass Realization
ODES OF OPERATIO
PRIMARY MODES Mode 1 In Mode 1, the ratio of the external clock frequency to the center frequency of each 2nd order section is internally fixed at 50:1 or 100:1. Figure 5 illustrates Mode 1 providing 2nd order notch, lowpass and bandpass outputs. Mode 1 can be used to make high order Butterworth lowpass filters; it can also be used to make low Q notches and for cascading 2nd order bandpass functions tuned at the same center frequency with unity gain. Mode 1 is faster than Mode 3. Note that Mode 1 can only be implemented with three of the four LTC1064 sections because Section D has no externally available summing node. Section D, however, can be internally connected in Mode 1 upon special request.
R3 R2 N R1 VIN S BP LP
8
+
NEGATIVE SUPPLY
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Noise All the noise performance mentioned excludes the clock feedthrough. Noise measurements will degrade if the already described grounding bypassing and buffering techniques are not practiced. The graph Wideband Noise vs Q in the Typical Performance Characteristics section is a very good representation of the noise performance of this device.
0.1µF 10k
+
1µF
FROM FILTER OUTPUT
–
4 LT ®318 LT1007 LT1056 7
R1 1M
VOUT
+
TO FILTER FIRST SUMMING NODE
R3 100k
+
LT1012 C1 0.1µF
–
R2 1M
0.1µF
1µF
C1 = C2 = LOW LEAKAGE FILM (I.E., POLYPROPYLENE) R1 = R2 = METAL FILM 1%
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C2 0.1µF
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Figure 4. Servo Amplifier
W
– +
+
Σ
–
∫
∫
1/4 LTC1064 AGND
fO =
R2 R3 R2 R3 fCLK ;f =f ;H =– ; HOBP = – ;H =– ;Q= R1 R1 ON1 R1 R2 100(50) n O OLP
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Figure 5. Mode 1: 2nd Order Filter Providing Notch, Bandpass and Lowpass
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LTC1064
ODES OF OPERATIO
Mode 3 Mode 3 is the second of the primary modes. In Mode 3, the ratio of the external clock frequency to the center frequency of each 2nd order section can be adjusted above or below 50:1 or 100:1. Side D of the LTC1064 can only be connected in Mode 3. Figure 6 illustrates Mode 3, the classical state variable configuration, providing highpass, bandpass and lowpass 2nd order filter functions. Mode 3 is slower than Mode 1. Mode 3 can be used to make high order all-pole bandpass, lowpass, highpass and notch filters.
When the internal clock-to-center frequency ratio is set at 50:1, the design equations for Q and bandpass gain are different from the 100:1 case. This was done to provide speed without penalizing the noise performance.
CC R4 R3 R2 HP R1 VIN S BP LP
– +
+
Σ
–
1/4 LTC1064
AGND
MODE 3 (100:1):
f fO = CLK 100 HOBP = – f fO = CLK 50
√ R2 ; Q = R3 √ R2 ; H R4 R2 R4
R3 R4 ;H =– R1 OLP R1
OHP = –
MODE 3 (50:1):
√
R2 1.005 R4 R2 ;Q= ; R2 R2 R4 – R3 16R4 R3 R4 R1 ; HOLP = – R3 R1 1– 16R4
√
HOHP = –
R2 ;H =– R1 OBP
NOTE: THE 50:1 EQUATIONS FOR MODE 3 ARE DIFFERENT FROM THE EQUATIONS FOR MODE 3 OPERATIONS OF THE LTC1059, LTC1060 AND LTC1061. START WITH fO, CALCULATE R2/R4, SET R4; FROM THE Q VALUE, CALCULATE R3: R3 = 1.005 Q R2
√
; THEN CALCULATE R1 TO SET R2 + R2 THE DESIRED GAIN. R4 16R4
Figure 6. Mode 3: 2nd Order Filter Providing Highpass, Bandpass and Lowpass
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SECONDARY MODES Mode 1b Mode 1b is derived from Mode 1. In Mode 1b, Figure 7, two additional resistors R5 and R6 are added to alternate the amount of voltage fed back from the lowpass output into the input of the SA (or SB or SC) switched-capacitor summer. This allows the filter’s clock-to-center frequency ratio to be adjusted beyond 50:1 or 100:1. Mode 1b maintains the speed advantages of Mode 1.
R6 R3 R2 N R1 VIN S BP LP R5
W
– +
+
Σ
–
∫
∫
1064 F07
1/4 LTC1064 AGND
fO =
fCLK 100(50)
√R5R6R6 ; f = f +
n
O; Q =
R3 R2
√R5R6R6 ; +
R2 R1 ; R6 R5 + R6
1064 F07 Eq
∫
∫
1064 F06
f HON1(f→ 0) = HON2 f→ CLK – = 2
R3 ; R5⏐ R6 ≤ 5k ⏐ R1
(
)
R2 ; HOLP = – R1
HOBP = –
R2 ; R1
Figure 7. Mode 1b: 2nd Order Filter Providing Notch, Bandpass and Lowpass
Mode 2 Mode 2 is a combination of Mode 1 and Mode 3, as shown in Figure 8. With Mode 2, the clock-to-center frequency ratio fCLK /fO is always less than 50:1 or 100:1. The advantage of Mode 2 is that it provides less sensitivity to resistor tolerances than does Mode 3. As in Mode 1, Mode 2 has a notch output which depends on the clock frequency and the notch frequency is therefore less than the center frequency fO.
1064 F06 Eq
When the internal clock-to-center frequency ratio is set at 50:1, the design equations for Q and bandpass gain are different from the 100:1 case.
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9
LTC1064
ODES OF OPERATIO
R4 R3 R2 N R1 S
VIN
– +
+
Σ
–
1/4 LTC1064 AGND
Figure 8. Mode 2: 2nd Order Filter Providing Notch, Bandpass and Lowpass
Mode 3a This is an extension of Mode 3 where the highpass and lowpass outputs are summed through two external resistors RH and RL to create a notch. This is shown in Figure 9. Mode 3a is more versatile than Mode 2 because the notch frequency can be higher or lower than the center frequency of the 2nd order section. The external op amp of Figure 9 is not always required. When cascading the sections of the LTC1064, the highpass and lowpass
CC R4 R3 R2 HP R1 VIN S MODE 3a (50:1): BP LP RL RG
– +
AGND
+
Σ
–
∫
RH
1/4 LTC1064
Figure 9. Mode 3a: 2nd Order Filter Providing Highpass, Bandpass, Lowpass and Notch
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MODE 2 (100:1): f fO = CLK 100
W
√
f R3 R2 1+ ; f = CLK ; Q = 50 R2 R4 n
√ √
R2 1+ ; HOLP = – R4
BP
LP
HOBP = –
R3 ; H (f→ 0) = – R1 ON1
R2 f R1 ; HON2 f→ CLK – = 2 R2 1+ R4
(
)
R2 R1 ; R2 1+ R4
R2 R1
∫
∫
1064 F08
MODE 2 (50:1):
f fO = CLK 50
√
R2 R2 1.005 1 + R2 fCLK R1 R4 ; H 1+ ;f = ;Q= ; OLP = – R4 n 50 R2 R2 R2 1+ – R3 16R4 R4
R2 R3 f R1 R1 HOBP = – ; HON1(f→ 0) = – ;H = f→ CLK = 2 R3 R2 ON2 1– 1+ 16R4 R4 NOTE: THE 50:1 EQUATIONS FOR MODE 2 ARE DIFFERENT FROM THE EQUATIONS FOR MODE 2 OPERATION OF THE LTC1059, LTC1060 AND LTC1061. START WITH fO, CALCULATE R2/R4, SET R4; FROM THE Q VALUE, CALCULATE R3: R3 = 1.005 Q R2
(
)
–
R2 R1
√
; THEN CALCULATE R1 TO SET THE DESIRED GAIN. R2 R2 + R4 16R4
1064 F08Eq
1+
outputs can be summed directly into the inverting input of the next section. The topology of Mode 3a is useful for elliptic highpass and notch filters with clock-to-cutoff frequency ratios higher than 100:1. This is often required to extend the allowed input signal frequency range and to avoid premature aliasing.
When the internal clock-to-center frequency ratio is set at 50:1, the design equations for Q and bandpass gain are different from the 100:1 case.
MODE 3a (100:1): f fO = CLK 100 HOLP = –
√ R2 ; f = 100 √ R ; H R4
n
fCLK
RH
L
OHP = –
R R4 R4 f ; H (f→ 0) = G ;H f→ CLK = RL R1 ON2 R1 ON1 2
HON(f = fO) = Q f fO = CLK 50
(
R RG R3 H – GH ;Q= RL OLP RH OHP R2
n CLK
√1 + R2 ; f = f50 R4
( )( ) ( ) ( √
R2 R3 ; HOBP = – ; R1 R1
) ( )( )
RG R2 ; RH R1 – R2 ; R1
√ R2 R4
f RH ; HOHP f→ CLK = 2 RL
)
∫
HOBP = –
–
NOTCH
R3 R2 1.005 R4 R1 R4 ; HOLP(f = 0) = – ;Q = R3 R1 R2 R2 1– – 16R4 R3 16R4
√
+
EXTERNAL OP AMP OR INPUT OP AMP OF THE LTC1064, SIDE A, B, C, D
NOTE: THE 50:1 EQUATIONS FOR MODE 3A ARE DIFFERENT FROM THE EQUATIONS FOR MODE 3A OPERATION OF THE LTC1059, LTC1060 AND LTC1061. START WITH fO, CALCULATE R2/R4, SET R4; FROM THE Q VALUE, CALCULATE R3: R2 R3 = ; THEN CALCULATE R1 TO 1.005 Q R2 √ R2 + 16R4 R4 SET THE DESIRED GAIN.
1064 F09Eq
1064 F09
LTC1064
TYPICAL APPLICATIO S
Wideband Bandpass: Ratio of High to Low Corner Frequency Equal to 2
R14 1 R23 R33 R43 2 3 4 5 C1 5V TO 8V 0.1µF R41 R31 R21 R11 VIN R13 RESISTOR VALUES: R11 = 16k R21 = 16k R31 = 7.32k R41 = 10k R12 = 10k R22 = 10k R32 = 22.6k R42 = 13.3k R13 = 23.2k R23 = 13.3k R33 = 21.5k R43 = 10k R14 = 6.8k R24 = 20k R34 = 15.4k R44 = 32.4k NOTE: FOR fCLK ≥ 3MHz, USE C1 = C2 = 22pF 6 7 8 9 10 11 12 INV B HPB/NB BPB LPB SB AGND V+ SA LPA BPA HPA/NA INV A LTC1064 INV C HPC/NC BPC LPC SC V– CLK 24 23 22 21 20 19 18 17 16 15 14 13 R42 R32 R22 R12 C2 fCLK ≤ 7MHz 0.1µF R24 R34 R44 VOUT –5V TO –8V
GAIN (dB)
Quad Bandpass Filter with Center Frequency Equal to fO, 2fO, 3fO and 4fO
10.5k R12 VIN1 R22 R32 1 2 3 4 5 6 5V TO 8V 0.1µF R31 R21 R11 VIN3 7 8 9 10 11 12 INV B HPB/NB BPB LPB SB AGND V+ SA LPA BPA HPA/NA INV A LTC1064 INV C HPC/NC BPC LPC SC 24 23 22 21 20
GAIN (dB)
50/100 LPD BPD HPD INV D
RESISTOR VALUES: R11 = 249k R21 = 10k R12 = 249k R22 = 10k R13 = 499k R23 = 10k R14 = 453k R24 = 10k
R31 = 249k R32 = 249k R33 = 174k R34 = 249k
U
Amplitude Response
15 0 –15 –30 –45 fCLK = 2MHz –60 –75 VS = ± 8V –105 10k –90 fCLK = 7MHz
50/100 LPD BPD HPD INV D
100k INPUT FREQUENCY (Hz)
1M
1064 TA04
1064 TA03
R13 R23 R33 R43 VIN2
5 0 –5 –10
Amplitude Response
fCLK = 2MHz
19 V– CLK 18 17 16 15 14 13 17.4k 20k 20k R44 R34 R24 fCLK
–5V TO –8V 0.1µF
–15 –20 –25 –30 –35 –40
R14 VIN4 20k
0
10
20
30
40
50
1064 TA06
INPUT FREQUENCY (kHz)
–
LT1056 VOUT
+
R43 = 17.8k R44 = 40.2k
1064 TA05
1064fb
11
LTC1064
TYPICAL APPLICATIO S
8th Order Bandpass Filter with 2 Stopband Notches
RL2 RH2 RH3 R12 R22 R32 R42 1 2 3 4 5 6 5V TO 8V 0.1µF R41 R31 R21 R11 VIN 7 8 9 10 11 12 INV B HPB/NB BPB LPB SB AGND V+ SA LPA BPA HPA/NA INV A LTC1064 INV C HPC/NC BPC LPC SC V– CLK 24 23 22 21 20 19 18 17 16 15 14 13 VOUT RESISTOR VALUES: R11 = 46.95k R21 = 10k R12 = 93.93k R22 = 10k R23 = 16.3k R24 = 13.19k R31 = 38.25k R32 = 81.5k R33 = 70.3k R34 = 39.42k R41 = 11.81k R42 = 14.72k R43 = 10k R44 = 10.5k R44
–60 10
GAIN (dB)
NOTE 1: THE V +, V – PINS SHOULD BE BYPASSED WITH A 0.1µF TO 0.22µF CERAMIC CAPACITOR, RIGHT AT THE PINS. NOTE 2: THE RATIOS OF ALL (R2/R4) RESISTORS SHOULD BE MATCHED TO BETTER THAN 0.25%. THE REMAINING RESISTORS SHOULD BE BETTER THAN 0.5% ACCURATE.
C-Message Filter
R13 1 R22 R32 R42 2 3 4 5 6 5V 7 R12 0.1µF R41 R31 R21 R11 VIN RESISTOR VALUES: R11 = 88.7k R21 = 10k R12 = 10k R22 = 44.8k R13 = 15.8k R23 = 48.9k R14 = 15.8k R24 = 44.8k 8 9 10 11 12 INV B HPB/NB BPB LPB SB AGND V+ SA LPA BPA HPA/NA INV A LTC1064 INV C HPC/NC BPC LPC SC 24 23 22 21 20 R23 R33 R43
10 0 –10 VS = ± 5V
19 V– CLK 18 17 16 15 14 13 R44 R34 R24
GAIN (dB)
R31 = 35.7k R32 = 33.2k R33 = 63.5k R34 = 16.5k
12
U
Amplitude Response
0 –10 VS = ± 5V fCLK = 1.28MHz PIN 17 AT V +
R23 R33 R43 RL3
–20 –30 –40 –50
–5V TO –8V 1.28MHz 0.1µF TO V + R34 R24
50/100 LPD BPD HPD INV D
–70 1 10 20 40 5 INPUT FREQUENCY (kHz) 100
1064 TA08
RL2 = 27.46k RL3 = 17.9k
RH2 = 6.9k RH3 = 69.7k
1064 TA07
Amplitude Response
R14
0.1µF –5V 3.5795MHz fCLK = 16
–20 –30 –40 –50 –60 –70 0 1 3 2 4 INPUT FREQUENCY (kHz) 5
1064 TA10
50/100 LPD BPD HPD INV D
VOUT R41 = 88.7k R42 = 24.9k R43 = 25.5k R44 = 24.9k
1064 TA09
1064fb
LTC1064
TYPICAL APPLICATIO S
8th Order Chebyshev Lowpass Filter with a Passband Ripple of 0.1dB and Cutoff Frequency up to 100kHz
R13 1 R22 R32 R12 R42 2 3 4 5 6 5V TO 8V 7 0.1µF R41 R31 R21 R11 VIN 8 9 10 11 12 INV B HPB/NB BPB LPB SB AGND V+ SA LPA BPA HPA/NA INV A LTC1064 INV C HPC/NC BPC LPC SC V 24 23 22 21 20 R23 R33 R43 R14 –5V TO –8V fCLK = 5MHz 5V TO 8V R44 R34 R24 0.1µF
– 19
GAIN (dB)
RESISTOR VALUES: R11 = 100.86k R21 = 16.75k R12 = 25.72k R22 = 20.93k R13 = 16.61k R23 = 10.18k R14 = 13.84k R24 = 11.52k
R31 = 23.6k R32 = 45.2k R33 = 68.15k R34 = 17.72k
FOR fCLK > 3MHz, ADD C2 = 10pF ACROSS R42 C3 = 10pF ACROSS R43 C4 = 10pF ACROSS R44 WIDEBAND NOISE = 170µVRMS
U
Amplitude Response
15 0 – 15 –30 –45 –60 –75 –90 VS = ± 8V fCLK = 5MHz PASSBAND RIPPLE = 0.1dB 100k INPUT FREQUENCY (Hz) 1M
1064 TA12
CLK
18 17 16 15 14 13
50/100 LPD BPD HPD INV D
–105 10k
VOUT
R41 = 99.73k R42 = 25.52k R43 = 99.83k R44 = 25.42k
1064 TA11
1064fb
13
LTC1064
TYPICAL APPLICATIO S
8th Order Clock-Sweepable Lowpass Elliptic Antialiasing Filter
RH1 RL1 RH2 RL2 1 R22 R32 R42 2 3 4 5 6 7.5V 0.1µF R43 R33 R23 7 8 9 10 11 12 INV B HPB/NB BPB LPB SB AGND V+ SA LPA BPA HPA/NA INV A LTC1064 INV C HPC/NC BPC LPC SC V– CLK 24 23 22 21 20 19 18 17 16 15 14 13 RL3 RH3 RESISTOR VALUES: R11 = 19.1k R21 = 10k R22 = 10k R23 = 11.3k R24 = 15.4k R31 = 13.7k R32 = 23.7k R33 = 84.5k R34 = 15.2k R41 = 15.4k R42 = 10.2k R43 = 10k R44 = 42.7k RL1 = 14k RL2 = 26.7k RL3 = 10k RH1 = 30.9k RH2 = 76.8k RH3 = 60.2k
1064 TA13
VOUT/VIN (dB)
50/100 LPD BPD HPD INV D
NOTE: FOR tCUTOFF >15kHz, ADD A 5pF CAPACITOR ACROSS R41 AND R43
14
U
Amplitude Response
R11 R21 R31 R41 VIN
0 –15 –30 –45 –60 –75 –90 –105 0 10 20 30 40 50 60 70 FREQUENCY (kHz)
VOUT
–7.5V fCLK ≤ 2MHz –7.5V R44 R34 R24 0.1µF
8TH ORDER CLOCK-SWEEPABLE LOWPASS ELLIPTIC ANTIALIASING FILTER MAINTAINS, FOR 0.1Hz ≤ fCUTOFF ≤ 20kHz, A ± 0.1dB MAX PASSBAND ERROR AND 72dB MIN STOPBAND ATTENUATION AT 1.5 × fCUTOFF TOTAL WIDEBAND NOISE = 150µVRMS, THD = 70dB (0.03%) FOR VIN = 3VRMS, fCLK /fCUTOFF = 100:1. THIS FILTER AVAILABLE AS LTC1064-1 WITH INTERNAL THIN FILM 1064 TA14 RESISTORS
1064fb
LTC1064
TYPICAL APPLICATIO S
Dual 4th Order Bessel Filter with 140kHz Cutoff Frequency
R13 R12 VIN1 R22 R32 R42 1 2 3 4 5 6 8V 0.1µF 7 8 9 R41 R31 R11 VIN2 R21 10 11 12 INV B HPB/NB BPB LPB SB AGND V+ SA LPA BPA HPA/NA INV A LTC1064 INV C HPC/NC BPC LPC SC V 24 23 22 21 20 R23 R33 R43
GAIN (dB) 15 0 – 15
18 7MHz CLOCK 17 50/100 8V 16 LPD R44 15 BPD R34 14 HPD R24 13 INV D R14 CLK
RESISTOR VALUES: R11 = 14.3k R21 = 13k R12 = 15.4k R22 = 15.4k R13 = 3.92k R23 = 20k R14 = 3.92k R24 = 20k
R31 = 7.5k R32 = 7.5k R33 = 27.4k R34 = 6.8k
WIDEBAND NOISE = 64µVRMS
8th Order Linear Phase (Bessel) Filter with
R11 VIN1 R21 R31 R41
1 2 3 4 5 6
INV B HPB/NB BPB LPB SB AGND V+ SA LPA BPA HPA/NA INV A LTC1064
HPC/NC BPC LPC SC V– CLK
19 18 17 16 15 14 13 R44 R34 R24 R14 fCLK ≤ 7MHz TO V +
5V TO 8V 0.1µF
7 8 9 R43 R33 10 11 12
–5V TO –8V 0.1µF VOUT
GAIN (dB)
FROM PIN 20
R13
R23
RESISTOR VALUES: R11 = 34.8k R21 = 34.8k R12 = 10.5k R22 = 45.3k R13 = 12.7k R23 = 34.8k R14 = 20k R24 = 34.8k
R31 = 14.3k R32 = 22.1k R33 = 24.3k R34 = 13.3k
WIDEBAND NOISE = 70µVRMS
U
Amplitude Response
VOUT1 –8V 0.1µF VOUT2
–30 –45 –60 –75 –90 VS = ± 8V fCLK = 7MHz 100k INPUT FREQUENCY (Hz) 1M
1064 TA16
– 19
–105 10k
R41 = 10k R42 = 10k R43 = 40k R44 = 10k
1064 TA15
fCLK 65 = f –3dB 1
R12
INV C
24 23 22 21 20 R22 R32 R42 TO R13
Amplitude Response
15 0 – 15 –30 –45 –60 –75 –90 –105 10k VS = ± 8V fCLK = 4.5MHz fCLK = 50% DUTY CYCLE f–3dB = 70kHz 100k INPUT FREQUENCY (Hz) 1M
1064 TA18
50/100 LPD BPD HPD INV D
R41 = 40.2k R42 = 39.2k R43 = 20k R44 = 20k
1064 TA17
1064fb
15
LTC1064
TYPICAL APPLICATIO S
Dual 5th Order Chebyshev Lowpass Filter with 50kHz and 100kHz Cutoff Frequencies
R14 R13a VIN2 R13b C2 1000pF R23 R33 R43 1 2 3 4 5 2pF 6 7 0.1µF 22pF 8 9 R41 R31 R11a VIN1 R11b C1 1000pF RESISTOR VALUES: R11a = 4.32k R21 = 11.8k R11b = 27.4k R22 = 20k R12 = 10.5k R23 = 11.8k R13a = 3k R24 = 20k R13b = 29.4k R14 = 10.5k R31 = 29.4k R32 = 21.5k R33 = 29.4k R34 = 21.6k R21 10 11 12 INV B HPB/NB BPB LPB SB AGND V+ SA LPA BPA HPA/NA INV A LTC1064 INV C HPC/NC BPC LPC SC V– CLK 24 23 22 21 20 19 18 17 16 15 14 13 R12 5MHz T2L R42 R32 R22 39pF 0.1µF VOUT1 fC = 50kHz R24 R34 4pF R44 VOUT2 fC = 100kHz –8V
GAIN (dB)
8V
16
U
Amplitude Response
15 PASSBAND RIPPLE = 0.2dB 0 – 15 –30 –45 –60 –75 –90 –105 10k 50k 100k INPUT FREQUENCY (Hz) 1M
1064 TA20
50/100 LPD BPD HPD INV D
R41 = 10k R42 = 31.6k R43 = 10k R44 = 31.6k
1064 TA19
1064fb
LTC1064
PACKAGE DESCRIPTIO
.025 .220 – .310 (5.588 – 7.874) (0.635) RAD TYP 1 .300 BSC (7.62 BSC) .015 – .060 (0.381 – 1.524) 11
.008 – .018 (0.203 – 0.457)
0° – 15°
NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP/PLATE OR TIN PLATE LEADS
U
J Package 24-Lead CERDIP (Narrow .300 Inch, Hermetic)
(Reference LTC DWG # 05-08-1110)
1.290 (32.77) MAX 24 23 22 21 20 19 18 17 16 15 14 13 2 .005 (0.127) MIN 3 4 5 6 7 8 9 10 12 .200 (5.080) MAX .125 (3.175) MIN .045 – .065 (1.143 – 1.651) .014 – .026 (0.360 – 0.660) .100 (2.54) BSC
J24 0801
OBSOLETE PACKAGE
1064fb
17
LTC1064
PACKAGE DESCRIPTIO
.255 ± .015* (6.477 ± 0.381)
.300 – .325 (7.620 – 8.255)
.020 (0.508) MIN .008 – .015 (0.203 – 0.381)
(
+.035 .325 –.015 +0.889 8.255 –0.381
)
.120 (3.048) MIN
INCHES MILLIMETERS *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .010 INCH (0.254mm)
NOTE: 1. DIMENSIONS ARE
18
U
N Package 24-Lead PDIP (Narrow .300 Inch)
(Reference LTC DWG # 05-08-1510)
1.265* (32.131) MAX 24 23 22 21 20 19 18 17 16 15 14 13 1 .130 ± .005 (3.302 ± 0.127) 2 3 4 5 6 7 8 9 10 11 12 .045 – .065 (1.143 – 1.651) .065 (1.651) TYP
N24 1103
.100 (2.54) BSC
.018 ± .003 (0.457 ± 0.076)
1064fb
LTC1064
PACKAGE DESCRIPTIO
.030 ±.005 TYP N
.050 BSC .045 ±.005 .598 – .614 (15.190 – 15.600) NOTE 4 20 19 18 17 16
.420 MIN
1
2
3
RECOMMENDED SOLDER PAD LAYOUT .291 – .299 (7.391 – 7.595) NOTE 4 .010 – .029 × 45° (0.254 – 0.737)
0° – 8° TYP
.005 (0.127) RAD MIN
.009 – .013 (0.229 – 0.330) NOTE: 1. DIMENSIONS IN
NOTE 3 .016 – .050 (0.406 – 1.270)
INCHES (MILLIMETERS) 2. DRAWING NOT TO SCALE 3. PIN 1 IDENT, NOTCH ON TOP AND CAVITIES ON THE BOTTOM OF PACKAGES ARE THE MANUFACTURING OPTIONS. THE PART MAY BE SUPPLIED WITH OR WITHOUT ANY OF THE OPTIONS 4. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm)
Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
U
SW Package 24-Lead Plastic Small Outline (Wide .300 Inch)
(Reference LTC DWG # 05-08-1620)
24 23 22 21 15 14 13 N .325 ±.005 NOTE 3 .394 – .419 (10.007 – 10.643) N/2 N/2 1 .093 – .104 (2.362 – 2.642) 2 3 4 5 6 7 8 9 10 11 12 .037 – .045 (0.940 – 1.143) .050 (1.270) BSC .004 – .012 (0.102 – 0.305) .014 – .019 (0.356 – 0.482) TYP
S24 (WIDE) 0502
1064fb
19
LTC1064
TYPICAL APPLICATIO S
Clock-Tunable, 30kHz to 90kHz 8th Order Notch Filter Providing Notch Depth in Excess of 60dB
R13 C2 1 R22 R32 R42 2 3 4 5 C1 8V 0.1µF R12 R31 R21 R11 VIN1 6 7 8 9 10 11 12 24 23 22 21 20 19 18 17 16 15 14 13 R44 R34 R24 RL4 0.1% RH4 0.1% RESISTOR VALUES: R11 = 50k R21 = 5k R12 = 15.4k R22 = 10k R13 = 10k R23 = 10k R14 = 9.09k R24 = 10k R31 = 50k R32 = 88.7k R33 = 100k R34 = 63.4k RG = 68.1k RL4 = 10k (0.1%) RH4 = 10k (0.1%) C1 = C2 = C3 = 15pF THE NOTCH DEPTH FROM 5kHz TO 30kHz IS 50dB WIDEBAND NOISE = 300µVRMS RG C3 –8V fCLK ≤ 5MHz 0.1µF R23 R33 R14 INV B HPB/NB BPB LPB SB AGND V+ SA LPA BPA HPA/NA INV A LTC1064 INV C HPC/NC BPC LPC SC V– CLK
GAIN (dB)
R42 = 48.7k R44 = 12.4k
RELATED PARTS
PART NUMBER LTC1061 LTC1068 Series LTC1164 LTC1264 DESCRIPTION Triple Universal Filter Building Block Quad Universal Building Blocks Low Power, Quad Universal Filter Building Block High Speed, Quad Universal Building Block COMMENT Three Filter Building Blocks in a 20-Pin Package fCLK:fO = 25:1, 50:1, 100:1 and 200:1 Low Noise, Low Power Pin-for-Pin LTC1064 Compatible Up to 250kHz Center Frequency
20
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ● FAX: (408) 434-0507
●
U
Amplitude Response
10 0 –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 –110 10 VS = ± 8V fCLK = 4MHz 20 30 40 50 60 INPUT FREQUENCY (kHz) 70 BW
50/100 LPD BPD HPD INV D
1064 TA22
–
LT1056 VOUT
+
1064 TA21
1064fb LT/LT 0905 REV B • PRINTED IN USA
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© LINEAR TECHNOLOGY CORPORATION 1989