lmf90 National Semiconductor Corporation, lmf90 Datasheet
lmf90
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lmf90 Summary of contents
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... LMF90 4th-Order Elliptic Notch Filter General Description The LMF90 is a fourth-order elliptic notch (band-reject) filter based on switched-capacitor techniques No external com- ponents are needed to define the response function The depth of the notch is set using a two-level logic input and the width is programmed using a three-level logic input Two ...
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... the number given in the Absolute Maximum Ratings whichever is lower For this JMAX when board mounted for the LMF90CCN and CIN 134 C W for the LMF90CCWM and the current at that pin should be limited The 20 mA ...
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Typical Performance Characteristics Notch Depth vs Clock Frequency Power Supply Current vs Power Supply Voltage Offset Voltage vs Supply Voltage Passband Width vs Supply Voltage Notch Depth vs Notch Depth Supply Voltage vs Temperature Power Supply Current Offset Voltage vs ...
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Typical Performance Characteristics Stopband Width vs Supply Voltage Clock-to-Center-Frequency Ratio Deviation vs Supply Voltage Positive Output Voltage Swing vs Load Resistance (Continued) Clock-to-Center-Frequency Stopband Width Ratio Deviation vs Temperature vs Clock Frequency Clock-to-Center-Frequency Ratio Deviation Output Swing vs Temperature vs ...
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... Definition of Terms A the maximum amount of gain variation within the fil- max ter’s passband (See Figure 1 ) For the LMF90 A the CLK pin is nominally equal the minimum attenuation within the notch’s stopband min ...
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... Passband Gain the notch filter’s gain for signal frequen- cies near The passband gain of a notch filter is CLK also called ‘‘H ’’ For the LMF90 the passband gain is ON nominally 0 dB Passband Ripple the variation in gain within the filter’s passband ...
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... LMF90 to notch the third harmonic Table I illustrates 18 different combinations of filter band- width depth and clock-to-center-frequency ratio obtained by choosing the appropriate W D and R programming volt- ages TABLE I Operation of LMF90 Programming Pins Values given are for nominal levels of attenuation ...
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... ALIASING Another important characteristic of sampled-data systems is their effect on signals at frequencies greater than one-half the sampling frequency (The LMF90’s sampling frequency is the same as the filter’s clock frequency This is the fre- quency at the CLK pin signal with a frequency greater than one-half the sampling frequency is applied to the input of a sampled-data system it will be ‘ ...
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... At frequencies well below the center frequency the input impedance appears to be resistive 2 5 POWER SUPPLY AND CLOCK OPTIONS The LMF90 is designed to operate from either single or dual power supply voltages from 5V to 15V In either case the supply pins should be well-bypassed to minimize any feed- through of power supply noise into the filter’ ...
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Applications Information DUAL-SUPPLY CLOCK OPTIONS FIGURE 6 Dual supply external CMOS-level clock Internal frequency divider disabled FIGURE 7 Dual supply TTL-level clock Internal frequency divider disabled (Continued 10354 – 10354 – 11 ...
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Applications Information DUAL-SUPPLY CLOCK OPTIONS FIGURE 8 Dual Supply external CMOS-level clock Internal frequency divider enabled Output of logic divider available on pin 6 FIGURE 9 Dual supply internal crystal clock oscillator Internal frequency divider enabled Output of ...
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Applications Information SINGLE-SUPPLY CLOCK OPTIONS a FIGURE 10 Single 5V supply external TTL-level clock Internal frequency divider disabled FIGURE 11 Single Internal frequency divider enabled Output of logic divider available on pin 6 (Continued supply external ...
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Applications Information SINGLE-SUPPLY CLOCK OPTIONS a FIGURE 12 Single 10V supply external TTL-level clock Internal frequency divider disabled a FIGURE 13 Single 10V supply external CMOS-level clock Internal frequency divider disabled (Continued 10354 – 16 ...
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Applications Information SINGLE-SUPPLY CLOCK OPTIONS FIGURE 14 Single Internal frequency divider enabled Output of logic divider available on pin FIGURE 15 Single 5V or 10V supply internal crystal clock oscillator Internal frequency divider enabled Output ...
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Typical Application 20 ...
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... Physical Dimensions inches (millimeters) 14 Lead Ceramic Dual-In-Line Package (J) Order Number LMF90CIJ LMF90CMJ LMF90CMJ 883 or LMF90CCJ 14 Lead Molded Package Small Outline 0 300 Wide Order Number LMF90CCWM or LMF90CIWM NS Package Number J14A NS Package Number M14B 21 ...
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... Physical Dimensions inches (millimeters) (Continued) 14 Lead Molded Dual-In-Line Package (N) Order Number LMF90CCN or LMF90CIN LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF NATIONAL SEMICONDUCTOR CORPORATION As used herein ...