Datasheet

ManualsBrandsLINEAR TECHNOLOGY ManualsLinear ICsLTC1064CSW#PBF

LTC1064

1064fb

INV B

HPB/NB

BPB

LPB

AGND

LPA

BPA

HPA/NA

INV A

INV C

HPC/NC

BPC

LPC

–

CLK

50/100

LPD

BPD

HPD

INV D

LTC1064

10k

18.25k

10.7k

10k

12.1k

17.4k

102k

13k

66.5k

26.7k

41.2k

12.7k

14k

121k

10k

22.1k

(FROM

, R

)

5MHz

0.1µF

–8V

PIN 12

OUT

1064 TA01

10k

49.9K

11.5K

FOR f

CLK

= 5MHz, ADD C1 = 10pF BETWEEN PINS 4, 1

C2 = 10pF BETWEEN PINS 21, 24

C3 = 27pF BETWEEN PINS 9, 12

WIDEBAND NOISE ≅ 140µV

RMS

■

Anti-Aliasing Filters

■

Wide Frequency Range Tracking Filters

■

Spectral Analysis

■

Loop Filters

■

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 build-

ing 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 fre-

quency 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 includ-

ing internal thin film resistors can be obtained for high

volume applications. Consult LTC Marketing for details.

APPLICATIO S

TYPICAL APPLICATIO

DESCRIPTIO

FEATURES

Low Noise, Fast, Quad

Universal Filter Building Block

Gain vs Frequency

Clock-Tunable 8th Order Cauer Lowpass Filter with f

CUTOFF

up to 100kHz

INPUT FREQUENCY (Hz)

GAIN (dB)

10k 100k 1M

1064 TA02

–15

–30

–45

–60

–75

–90

–105

–120

–135

CLK

= 5MHz

RIPPLE = ±0.1dB

CLK

= 1MHz

RIPPLE = ±0.05dB

, 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.

Summary of content (20 pages)

PAGE 1
LTC1064 Low Noise, Fast, Quad Universal Filter Building Block U FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ DESCRIPTIO 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.
PAGE 2
LTC1064 U W W W ABSOLUTE AXI U RATI GS (Note 1) 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 Storage Temperature Range ................ – 65°C to 150°C Lead Temperature (Soldering, 10 sec).................
PAGE 3
LTC1064 ELECTRICAL CHARACTERISTICS (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.
PAGE 4
LTC1064 W BLOCK DIAGRA HPA/NA (11) BPA (10) LPA (9) V + (7) INV A (12) – AGND (6) + + – CLK (18) LPB (4) SA (8) + Σ +∫ V – (19) +∫ – HPC/NC (23) – + LPC (21) BPC (22) SB (5) + Σ +∫ 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 – HPD (14) INV D (13) 50/100 (17) +∫ BPB (3) + INV C (24) +∫ – HPB/NB (2) INV B (1) Σ LPD (16) BPD (15) SC (20) BY TYING PIN 17 TO AGND, SECTIONS B,
PAGE 5
LTC1064 U W TYPICAL PERFORMANCE CHARACTERISTICS Mode 2, (fCLK /fO) = 25:1 5 Q=5 CC = 22pF Q=2 CC = 39pF 0 10 VS = ±7.5V 5 0 –5 CENTER FREQUENCY ERROR (%) CENTER FREQUENCY ERROR (%) –5 15 TA = 25°C PIN 17 AT V – (R2/R4) = 3 Q=5 Q = 10 1.5 Q=2 Q=5 1.0 0.5 0 0 20 40 60 80 100 120140160180 200 CENTER FREQUENCY (kHz) 20 Q ERROR (%) 10 VS = ±2.5V VS = ±5V 20 TA = 25°C CC = 5pF R2 = R4 Q=5 Q = 10 VS = ±5V 15 VS = ±2.5V 10 5 VS = ±7.5V 0 –5 1.5 VS = ±5V 1.0 VS = ±2.5V 0.5 VS = ±7.
PAGE 6
LTC1064 U U U 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. AGND (Pin 6): Analog Ground. When the LTC1064 operates with dual supplies, Pin 6 should be tied to system ground.
PAGE 7
LTC1064 U W U U APPLICATIONS INFORMATION ANALOG CONSIDERATIONS 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. 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.
PAGE 8
LTC1064 U W U U APPLICATIONS INFORMATION Offset Nulling Noise 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. All the noise performance mentioned excludes the clock feedthrough.
PAGE 9
LTC1064 W U ODES OF OPERATIO Mode 3 SECONDARY MODES 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.
PAGE 10
LTC1064 W U ODES OF OPERATIO R4 MODE 2 (100:1): R3 R2 N R1 – VIN BP S + Σ – ∫ + LP ∫ f fO = CLK 100 √ HOBP = – R3 ; H (f→ 0) = – R1 ON1 f fO = CLK 50 MODE 2 (50:1): √ f R3 R2 1+ ; f = CLK ; Q = 50 R2 R4 n √ R2 1+ ; HOLP = – R4 ( ) R2 f R1 ; HON2 f→ CLK =– 2 R2 1+ R4 R2 R1 ; R2 1+ R4 R2 R1 √ R2 R2 1.
PAGE 11
LTC1064 U TYPICAL APPLICATIO S Wideband Bandpass: Ratio of High to Low Corner Frequency Equal to 2 R14 2 R33 3 R43 4 5 6 C1 7 5V TO 8V 0.1µF 8 R41 9 R31 10 R21 11 R11 12 VIN INV B INV C HPB/NB HPC/NC BPB BPC LPB LPC SB SC AGND V– LTC1064 V+ SA CLK 50/100 LPA LPD BPA BPD HPA/NA HPD INV A INV D Amplitude Response 24 23 R24 15 22 R34 0 21 R44 VOUT 20 19 18 fCLK = 7MHz –15 –5V TO –8V 0.
PAGE 12
LTC1064 U TYPICAL APPLICATIO S 8th Order Bandpass Filter with 2 Stopband Notches RL2 RH2 Amplitude Response RH3 1 R22 2 R32 3 R42 4 5 6 7 5V TO 8V 0.1µF R41 8 R31 10 R21 11 R11 9 12 VIN INV B INV C HPB/NB HPC/NC BPB BPC LPB LPC SB SC AGND V– V+ LTC1064 CLK 50/100 SA LPD LPA BPA BPD HPA/NA HPD INV D INV A 24 10 23 R23 22 R33 21 R43 –10 RL3 20 19 18 –5V TO –8V 1.28MHz 17 0.1µF TO V + 16 R44 15 R34 14 R24 VS = ±5V fCLK = 1.
PAGE 13
LTC1064 U TYPICAL APPLICATIO S 8th Order Chebyshev Lowpass Filter with a Passband Ripple of 0.1dB and Cutoff Frequency up to 100kHz R13 R22 R32 R12 R42 2 3 4 5 6 7 5V TO 8V 0.1µF 8 R41 R31 R21 R11 VIN 9 10 11 12 INV B INV C HPB/NB HPC/NC BPB BPC LPB LPC SB SC AGND V+ V LTC1064 SA 50/100 LPA LPD BPA BPD HPA/NA HPD INV A 23 R23 15 22 R33 0 21 R43 – 15 20 R14 – 19 CLK INV D Amplitude Response 24 18 17 –5V TO –8V GAIN (dB) 1 0.1µF fCLK = 5MHz R31 = 23.
PAGE 14
LTC1064 U TYPICAL APPLICATIO S 8th Order Clock-Sweepable Lowpass Elliptic Antialiasing Filter RH1 RL1 RH2 Amplitude Response RL2 2 R32 3 R42 4 5 6 7 7.5V 0.1µF 8 R43 9 R33 10 R23 11 12 INV B INV C HPB/NB HPC/NC BPB BPC LPB LPC SB SC V– AGND V+ LTC1064 SA LPA CLK 50/100 LPD BPA BPD HPA/NA HPD INV A INV D R11 24 23 R21 22 R31 21 R41 VIN –15 –30 20 19 18 17 –7.5V fCLK ≤ 2MHz 0.
PAGE 15
LTC1064 U TYPICAL APPLICATIO S Dual 4th Order Bessel Filter with 140kHz Cutoff Frequency R13 1 R22 R32 R42 2 3 4 5 6 7 8V 0.1µF 8 9 R41 R31 R11 R21 VIN2 10 11 12 INV B INV C HPB/NB HPC/NC BPB BPC LPB LPC SB SC AGND V LTC1064 V+ Amplitude Response 24 23 R23 22 R33 0 21 R43 – 15 20 VOUT1 – 19 –8V 0.1µF 18 7MHz CLOCK 17 50/100 8V 16 LPD R44 15 BPD R34 14 HPD R24 13 INV D R14 SA LPA BPA HPA/NA INV A RESISTOR VALUES: R11 = 14.3k R21 = 13k R12 = 15.4k R22 = 15.4k R13 = 3.
PAGE 16
LTC1064 U TYPICAL APPLICATIO S Dual 5th Order Chebyshev Lowpass Filter with 50kHz and 100kHz Cutoff Frequencies R14 R13b C2 1000pF 1 R23 2 R33 3 R43 4 5 2pF 6 7 8V 0.1µF 22pF 8 9 R11a VIN1 R11b R41 10 R31 11 R21 12 INV B INV C HPB/NB HPC/NC BPB BPC LPB LPC SB SC AGND V– V+ LTC1064 SA LPA BPA HPA/NA INV A CLK 50/100 LPD BPD HPD INV D 24 Amplitude Response 23 R24 22 R34 21 R44 15 PASSBAND RIPPLE = 0.2dB VOUT2 fC = 100kHz 20 19 18 17 0 4pF –8V 5MHz T2L 0.
PAGE 17
LTC1064 U PACKAGE DESCRIPTIO 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 1 2 3 4 5 6 7 8 9 10 11 12 .025 .220 – .310 (5.588 – 7.874) (0.635) RAD TYP .005 (0.127) MIN .300 BSC (7.62 BSC) .200 (5.080) MAX .015 – .060 (0.381 – 1.524) .008 – .018 (0.203 – 0.457) 0° – 15° NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP/PLATE OR TIN PLATE LEADS .125 (3.175) MIN .045 – .065 (1.143 – 1.
PAGE 18
LTC1064 U PACKAGE DESCRIPTIO 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 2 3 4 5 6 7 8 9 10 11 12 .255 ± .015* (6.477 ± 0.381) .300 – .325 (7.620 – 8.255) .130 ± .005 (3.302 ± 0.127) .045 – .065 (1.143 – 1.651) .020 (0.508) MIN .008 – .015 (0.203 – 0.381) ( +.035 .325 –.015 +0.889 8.255 –0.381 ) .120 (3.048) MIN .065 (1.651) TYP N24 1103 .100 (2.54) BSC .018 ± .003 (0.457 ± 0.
PAGE 19
LTC1064 U PACKAGE DESCRIPTIO SW Package 24-Lead Plastic Small Outline (Wide .300 Inch) (Reference LTC DWG # 05-08-1620) .050 BSC .045 ±.005 .030 ±.005 TYP N 24 23 22 21 .598 – .614 (15.190 – 15.600) NOTE 4 20 19 18 17 16 15 14 13 N .325 ±.005 .420 MIN .394 – .419 (10.007 – 10.643) NOTE 3 1 2 3 N/2 N/2 RECOMMENDED SOLDER PAD LAYOUT .005 (0.127) RAD MIN .009 – .013 (0.229 – 0.330) .291 – .299 (7.391 – 7.595) NOTE 4 .010 – .029 × 45° (0.254 – 0.737) 2 3 4 5 6 7 8 .093 – .
PAGE 20
LTC1064 U TYPICAL APPLICATIO S Clock-Tunable, 30kHz to 90kHz 8th Order Notch Filter Providing Notch Depth in Excess of 60dB R13 C2 R14 R22 2 R32 3 R42 4 5 6 C1 7 8V 0.1µF 8 R12 9 R31 10 R21 R11 11 12 VIN1 INV B INV C HPB/NB HPC/NC BPB BPC LPB LPC SB SC AGND V– LTC1064 V+ CLK 50/100 SA LPA LPD BPA BPD HPA/NA HPD INV A INV D Amplitude Response 24 23 R23 22 R33 R31 = 50k R32 = 88.7k R33 = 100k R34 = 63.4k R42 = 48.7k 0 21 –20 0.