LTC1064-7CSW

LTC1064-7 Linear Phase, 8th Order Lowpass Filter FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ DESCRIPTIO Steeper Roll-Off Than 8th Order Bessel Filters fCUTOFF up to 100kHz Phase Equalized Filter in 14-Pin Package Phase and Group Delay Response Fully Tested Transient Response Exhibits 5% Overshoot and No Ringing Wide Dynamic Range 72dB THD or Better Throughout a 50kHz Passband No External Components Needed Available in 14-Pin DIP and 16-Pin SO Wide Packages The LTC®1064-7 is a clock-tunable monolithic 8th order lowpass filter with linear passband phase and flat group delay. The amplitude response approximates a maximally flat passband while it exhibits steeper roll-off than an equivalent 8th order Bessel filter. For instance, at twice the cutoff frequency the filter attains 34dB attenuation (vs 12dB for Bessel), while at three times the cutoff frequency, the filter attains 68dB attenuation (vs 30dB for Bessel). The cutoff frequency of the LTC1064-7 is tuned via an external TTL or CMOS clock. The LTC1064-7 features wide dynamic range. With single 5V supply, the S/N + THD is 76dB. Optimum 92dB S/N is obtained with ±7.5V supplies. The clock-to-cutoff frequency ratio of the LTC1064-7 can be set to 50:1 (Pin 10 to V +) or 100:1 (Pin 10 to V –). When the filter operates at clock-to-cutoff frequency ratio of 50:1, the input is double-sampled to lower the risk of aliasing. The LTC1064-7 is pin-compatible with the LTC1064-X series, LTC1164-7 and LTC1264-7. , LTC and LT are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. APPLICATIO S ■ ■ ■ Data Communication Filters Time Delay Networks Phase-Matched Filters TYPICAL APPLICATIO 1 VIN 2 3 7.5V 4 5 6 7 LTC1064-7 14 13 12 11 10 9 8 80kHz Linear Phase Lowpass Filter –7.5V 7.5V VOUT 1064-7 TA01 NOTE: THE POWER SUPPLIES SHOULD BE BYPASSED BY A 0.1µF CAPACITOR CLOSE TO THE PACKAGE AND ANY PRINTED CIRCUIT BOARD ASSEMBLY SHOULD MAINTAIN A DISTANCE OF AT LEAST 0.2 INCHES BETWEEN ANY OUTPUT OR INPUT PIN AND THE fCLK LINE. 1V/DIV CLK = 4MHz VS = ± 7.5V fCLK = 4MHz RATIO = 50:1 U Eye Diagram 1µs/DIV 1064-7 TA02 U U 10647fb 1 LTC1064-7 ABSOLUTE AXI U RATI GS Total Supply Voltage (V + to V –) .......................... 16.5V Power Dissipation ............................................. 400mW Burn-In Voltage ................................................... 16.5V Voltage at Any Input ..... (V – – 0.3V) ≤ VIN ≤ (V + + 0.3V) Storage Temperature Range ................ – 65°C to 150°C PACKAGE/ORDER I FOR ATIO TOP VIEW NC VIN GND V+ GND LP (A) INV (A) 1 2 3 4 5 6 7 14 RIN (A) 13 NC 12 V – 11 fCLK 10 50/100 9 8 VOUT NC ORDER PART NUMBER LTC1064-7CN N PACKAGE 14-LEAD PLASTIC DIP TJMAX = 110°C, θJA = 65°C/W (N) J PACKAGE 14-LEAD CERAMIC DIP TJMAX = 150°C, θJA = 65°C/W (J) OBSOLETE PACKAGE Consider the N Package as an Alternate Source LTC1064-7CJ LTC1064-7MJ 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. The ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C.VS = ± 7.5V, RL = 10k, TA = 25°C, fCUTOFF = 10kHz or 20kHz, fCLK = 1MHz, TTL or CMOS level (maximum clock rise and fall time ≤ 1µs) and all gain measurements are referenced to passband gain, unless otherwise specified. The filter cutoff frequency is abbreviated as fCUTOFF or fC. PARAMETER Passband Gain Gain at 0.5 fCUTOFF Gain at 0.75 fCUTOFF Gain at fCUTOFF Gain at 2 fCUTOFF Gain with fCLK = 20kHz Gain with fCLK = 400kHz, VS = ± 2.375V Phase Factor (F ) Phase = 180° – F (f/fC) (Note 2) CONDITIONS 0.1Hz ≤ f ≤ 0.25 fCUTOFF fTEST = 5kHz, (fCLK /fC) = 50:1 fTEST = 10kHz, (fCLK /fC) = 50:1 fTEST = 5kHz, (fCLK /f C) = 100:1 fTEST = 15kHz, (fCLK /fC) = 50:1 fTEST = 20kHz, (fCLK /fC) = 50:1 fTEST = 10kHz, (fCLK /fC) = 100:1 fTEST = 40kHz, (fCLK /fC) = 50:1 fTEST = 20kHz, (fCLK /fC) = 100:1 fTEST = 200Hz, (fCLK /fC) = 100:1 fTEST = 4kHz, (fCLK /fC) = 50:1 fTEST = 8kHz, (fCLK /fC) = 50:1 0.1Hz ≤ f ≤ fCUTOFF (fCLK /fC) = 50:1 (fCLK /fC) = 100:1 (fCLK /fC) = 50:1 (fCLK /fC) = 100:1 MIN ● ● ● ● ● ● ● ● ELECTRICAL CHARACTERISTICS 2 U U W WW U W (Note 1) Operating Temperature Range LTC1064-7C ....................................... – 40°C to 85°C LTC1064-7M OBSOLETE .............. – 55°C to 125°C Lead Temperature (Soldering, 10 sec)................. 300°C TOP VIEW NC 1 VIN 2 GND 3 V+ 4 16 RIN (A) 15 NC 14 V – 13 NC 12 fCLK 11 50/100 10 NC 9 VOUT ORDER PART NUMBER LTC1064-7CSW GND 5 NC 6 LP (A) 7 INV (A) 8 SW PACKAGE 16-LEAD PLASTIC SO (WIDE) TJMAX = 110°C, θJA = 85°C/W TYP 0.10 – 0.35 – 0.35 –1.0 – 3.4 – 4.5 – 34.0 – 34.5 – 4.3 – 0.3 – 3.3 430 ± 2.0 421 ± 2.5 430 421 MAX 0.65 0.15 1.25 – 0.35 – 2.50 – 3.75 – 31.75 – 31.75 – 3.5 0.25 – 2.00 UNITS dB dB dB dB dB dB dB dB dB dB dB Deg Deg Deg Deg 10647fb – 0.60 – 0.90 – 1.30 – 2.0 – 4.50 – 5.75 – 36.5 – 37.0 – 6.5 – 0.9 – 4.5 ● ● 422 414 437 429 LTC1064-7 ELECTRICAL CHARACTERISTICS PARAMETER Phase Nonlinearity (Notes 2, 4) The ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VS = ± 7.5V, RL = 10k, fCUTOFF = 10kHz or 20kHz, fCLK = 1MHz, TTL or CMOS level (maximum clock rise and fall time ≤ 1µs) and all gain measurements are referenced to passband gain, unless otherwise specified. The filter cutoff frequency is abbreviated as fCUTOFF or fC. CONDITIONS (fCLK /fC) = 50:1 (fCLK /fC) = 100:1 (fCLK /fC) = 50:1 (fCLK /fC) = 100:1 (fCLK /fC) = 50:1, f ≤ fCUTOFF (fCLK /fC) = 100:1, f ≤ fCUTOFF (fCLK /fC) = 50:1, f ≤ fCUTOFF (fCLK /fC) = 100:1, f ≤ fCUTOFF (fCLK /fC) = 50:1, f ≤ fCUTOFF (fCLK /fC) = 100:1, f ≤ fCUTOFF (fCLK /fC) = 50:1, f ≤ fCUTOFF (fCLK /fC) = 100:1, f ≤ fCUTOFF (fCLK /fC) = 50:1 (fCLK /fC) = 100:1 VS = 5V (AGND = 2V) VS = ± 5V VS = ± 7.5V 50:1 VS = ± 2.5V VS = ± 5V VS = ± 7.5V VS = ± 2.375V VS = ± 5V VS = ± 7.5V 50:1, VS = ± 5V 100:1, VS = ± 5V 50:1, VS = ± 5V 100:1, VS = ± 5V VS = ± 2.375V, TA = 25°C VS = ± 5V, TA = 25°C VS = ± 7.5V, TA = 25°C Power Supply Range MIN TYP ±1.0 ±1.0 MAX UNITS % % % % µs µs µs µs % % % % kHz kHz MHz MHz MHz µVRMS µVRMS µVRMS µVRMS kΩ V V V mV mV µV/°C µV/°C mA mA mA mA mA mA V ● ● ± 2.0 ± 2.0 Group Delay (td) td = (F /360)(1/ fC) (Note 3) Group Delay Deviation (Notes 3, 4) ● ● 58.6 115.0 59.7 ± 0.5 117.0 ± 1.0 59.7 117.0 ±1.0 ±1.0 60.7 119.0 ● ● ± 2.0 ± 2.0 Input Frequency Range (Table 9) Maximum fCLK Clock Feedthrough (f ≥ fCLK) Wideband Noise (1Hz ≤ f ≤ fCLK) Input Impedance Output DC Voltage Swing (Note 5) Output DC Offset Output DC Offset TempCo Power Supply Current ● ● 25 ± 1.0 ± 2.1 ± 3.0 80kHz) 2.7VRMS (fIN > 80kHz) 1.4VRMS (fIN > 500kHz) 1.6VRMS (fIN > 80kHz) 0.7VRMS (fIN > 400kHz) 0.5VRMS (fIN > 250kHz) 2V/DIV Table 9. Maximum VIN vs VS and Clock Table 10. Transient Response of LTC Lowpass Filters DELAY RISE SETTLING TIME* TIME** TIME*** LOWPASS FILTER (SEC) (SEC) (SEC) LTC1064-3 Bessel 0.50/fC 0.34/fC 0.80/fC LTC1164-5 Bessel 0.43/fC 0.34/fC 0.85/fC LTC1164-6 Bessel 0.43/fC 0.34/fC 1.15/fC LTC1264-7 Linear Phase 1.15/fC 0.36/fC 2.05/fC LTC1164-7 Linear Phase 1.20/fC 0.39/fC 2.2/fC LTC1064-7 Linear Phase 1.20/fC 0.39/fC 2.2/fC LTC1164-5 Butterworth 0.80/fC 0.48/fC 2.4/fC LTC1164-6 Elliptic 0.85/fC 0.54/fC 4.3/fC LTC1064-4 Elliptic 0.90/fC 0.54/fC 4.5/fC LTC1064-1 Elliptic 0.85/fC 0.54/fC 6.5/fC * To 50% ± 5%, ** 10% to 90% ± 5%, *** To 1% ± 0.5% OVERSHOOT (%) 0.5 0 1 5 5 5 11 18 20 20 ts INPUT 90% OUTPUT Table 11. Aliasing (fCLK = 100kHz) INPUT FREQUENCY (VIN = 1VRMS, fIN = fCLK ± fOUT) (kHz) 50:1, fCUTOFF = 2kHz 190 (or 210) 195 (or 205) 196 (or 204) 197 (or 203) 198 (or 202) 199.5 (or 200.5) 100:1, fCUTOFF = 1kHz 97 (or 103) 97.5 (or 102.5) 98 (or 102) 98.5 (or 101.5) 99 (or 101) 99.5 (or 100.5) OUTPUT LEVEL (Relative to Input, 0dB = 1VRMS) (dB) –76.1 – 51.9 – 36.3 – 18.4 – 3.0 – 0.2 –74.2 – 53.2 – 36.9 – 19.6 – 5.2 – 0.7 OUTPUT FREQUENCY (Aliased Frequency fOUT = ABS [fCLK ± fIN]) (kHz) 10.0 5.0 4.0 3.0 2.0 0.5 3.0 2.5 2.0 1.5 1.0 0.5 12 U Transient Response 50µs/DIV VS = ± 7.5V, fIN = 2kHz ± 3V fCLK = 1MHz, RATIO = 50:1 1064-7 F05 W U UO Figure 5. 50% td 10% tr RISE TIME (tr) = 0.39 ± 5% fCUTOFF 2.2 SETTLING TIME (ts) = ± 5% f (TO 1% of OUTPUT) CUTOFF 1.2 DELAY TIME (td) = GROUP DELAY ≈ fCUTOFF (TO 50% OF OUTPUT) 1064-7 F06 Figure 6. Aliasing Aliasing is an inherent phenomenon of sampled data systems and it occurs when input frequencies close to the sampling frequency are applied. For the LTC1064-7 case at 100:1, an input signal whose frequency is in the range of fCLK ± 3%, will be aliased back into the filter’s passband. If, for instance, an LTC1064-7 operating with a 100kHz clock and 1kHz cutoff frequency receives a 98kHz, 10mV input signal, a 2kHz, 143µVRMS alias signal will appear at its output. When the LTC1064-7 operates with a clock-tocutoff frequency of 50:1, aliasing occurs at twice the clock frequency. Table 11 shows details. 10647fb LTC1064-7 PACKAGE DESCRIPTIO .300 BSC (7.62 BSC) .008 – .018 (0.203 – 0.457) NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP/PLATE OR TIN PLATE LEADS U J Package 14-Lead CERDIP (Narrow .300 Inch, Hermetic) (Reference LTC DWG # 05-08-1110) .785 (19.939) MAX 14 13 12 11 10 9 8 .005 (0.127) MIN .025 (0.635) RAD TYP .220 – .310 (5.588 – 7.874) 1 2 3 4 5 6 7 .200 (5.080) MAX .015 – .060 (0.381 – 1.524) 0° – 15° .045 – .065 (1.143 – 1.651) .014 – .026 (0.360 – 0.660) .100 (2.54) BSC .125 (3.175) MIN J14 0801 OBSOLETE PACKAGE 10647fb 13 LTC1064-7 PACKAGE DESCRIPTIO .300 – .325 (7.620 – 8.255) .008 – .015 (0.203 – 0.381) +.035 .325 –.015 .005 (0.127) .100 MIN (2.54) BSC ( +0.889 8.255 –0.381 ) 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 14 U N Package 14-Lead PDIP (Narrow .300 Inch) (Reference LTC DWG # 05-08-1510) .770* (19.558) MAX 14 13 12 11 10 9 8 .255 ± .015* (6.477 ± 0.381) 1 .130 ± .005 (3.302 ± 0.127) .020 (0.508) MIN 2 3 4 5 6 7 .045 – .065 (1.143 – 1.651) .065 (1.651) TYP .120 (3.048) MIN .018 ± .003 (0.457 ± 0.076) N14 1103 10647fb LTC1064-7 PACKAGE DESCRIPTIO .030 ±.005 TYP N .420 MIN 1 2 3 RECOMMENDED SOLDER PAD LAYOUT 1 .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 3 .016 – .050 (0.406 – 1.270) NOTE: 1. DIMENSIONS IN 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 16-Lead Plastic Small Outline (Wide .300 Inch) (Reference LTC DWG # 05-08-1620) .050 BSC .045 ±.005 .398 – .413 (10.109 – 10.490) NOTE 4 16 15 14 13 12 11 10 9 N .325 ±.005 NOTE 3 .394 – .419 (10.007 – 10.643) N/2 N/2 2 3 4 5 6 7 8 .093 – .104 (2.362 – 2.642) .037 – .045 (0.940 – 1.143) .050 (1.270) BSC .004 – .012 (0.102 – 0.305) .014 – .019 (0.356 – 0.482) TYP S16 (WIDE) 0502 10647fb 15 LTC1064-7 TYPICAL APPLICATIO U Eye Diagram –7.5V 7.5V VOUT 1064-7 TA01 80kHz Linear Phase Lowpass Filter 1 VIN 2 3 7.5V 4 5 6 7 LTC1064-7 14 13 12 11 10 9 8 NOTE: THE POWER SUPPLIES SHOULD BE BYPASSED BY A 0.1µF CAPACITOR CLOSE TO THE PACKAGE AND ANY PRINTED CIRCUIT BOARD ASSEMBLY SHOULD MAINTAIN A DISTANCE OF AT LEAST 0.2 INCHES BETWEEN ANY OUTPUT OR INPUT PIN AND THE fCLK LINE. 1V/DIV CLK = 4MHz VS = ± 7.5V fCLK = 4MHz RATIO = 50:1 1µs/DIV 1064-7 TA02 RELATED PARTS PART NUMBER LTC1064 LTC1064-1/2/3/4 LTC1164 LTC1164-5/6/7 LTC1264 LTC1264-7 LT6600-2.5 LT6600-10 DESCRIPTION Universal Filter Building Block 8th Order Low Pass Filters, FO Max = 100kHz Universal Filter Building Block 8th Order Low Pass Filters, FO Max = 20kHz Universal Filter Building Block 8th Order Low Pass Filter, FO Max = 200kHz Low Noise Differential Amp and 10MHz Lowpass Low Noise Differential Amp and 20MHz Lowpass COMMENTS Allows for Bandpass (Up to 50kHz) Using External Resistors Elliptic, Butterworth, Bessel, Cauer Allows for Bandpass (Up to 20kHz) Using External Resistors Butterworth, Bessel or Elliptic Allows for Bandpass (Up to 100kHz) Using External Resistors Flat Group Delay, High Speed Lowpass Filter 55µVRMS Noise 100kHz to 10MHz 3V Supply 86µVRMS Noise 100kHz to 20MHz 3V Supply 10647fb 16 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● LT/LT 0905 REV B • PRINTED IN USA www.linear.com © LINEAR TECHNOLOGY CORPORATION 1992