MAX261BEWG Maxim Integrated Products, MAX261BEWG Datasheet

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... CLK CLK OSC CLKOUT B A CRYSTAL FOURTH-ORDER BANDPASS FILTER ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. Microprocessor Programmable Universal Active Filters o Filter Design Software Available o Microprocessor Interface o 64-Step Center Frequency Control ...

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Microprocessor Programmable Universal Active Filters ABSOLUTE MAXIMUM RATINGS + - Total Supply Voltage ( .............................................15V Input Voltage, any pin ..........................(V Input Current, any pin ......................................................±50mA Power Dissipation Plastic DIP (derate 8.33mW/°C above 70°C) ...............660mW CERDIP (derate 12.5mW/°C ...

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ELECTRICAL CHARACTERISTICS (continued +5V -5V, CLK = CLK = ±5V 350kHz for the MAX260 and 1.5MHz for the MAX261/MAX262 MAX260/MAX261 and 139.80 for MAX262, Filter Mode 1, T PARAMETER T A ...

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Microprocessor Programmable Universal Active Filters ELECTRICAL CHARACTERISTICS (for V± = ±2.5V ±5 +2.37V -2.37V, CLK = CLK A MAX260/MAX261 and 139.80 for MAX262, Filter Mode 1, T PARAMETER f Center Frequency Range 0 Maximum ...

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PIN NAME MAX261/ MAX260 MAX262 + Positive supply voltage - Negative supply voltage Analog Ground. Connect to the system ground for dual supply operation or mid-supply for single sup GND ply operation. ...

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Microprocessor Programmable Universal Active Filters (T = +25°C, unless otherwise noted ERROR vs. CLOCK FREQUENCY MAX260 30 ±5V MODE 4 25° ¡ CLK 0 MODES 2 & ...

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SCN = SWITCH-CAPACITOR NETWORK IN SCN MODE SELECT M0 M1 Figure 1. Filter Block Diagram (One Second-Order Section) Each MAX260/MAX261/MAX262 contains two second- order switched-capacitor active filters. Figure 1 shows the filter's state variable topology, employed with ...

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Microprocessor Programmable Universal Active Filters 100 AB$ = "FILTER A" : GOSUB 150 : REM GET DATA FOR SECTION A 110 ADD = 0 : GOSUB 220 : REM WRITE DATA TO THE PRINTER PORT 120 AB$ = "FILTER B" ...

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Step 2—Generate Programming Starting with the f and Q values obtained in Step 1, use 0 the program “MPP” to generate the digital coefficients that program each second-order section's f program displays values for “N” (“ for f ...

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Microprocessor Programmable Universal Active Filters Table 1. Typical Clock and Center Frequency Limits PART Q MODE f CLK 1 1 1Hz–400kHz 1 2 1Hz–425kHz 1 3 1Hz–500kHz 1 4 1Hz–400kHz 8 1 1Hz–500kHz 8 2 1Hz–700kHz MAX260 8 3 1Hz–700kHz ...

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Table Program Selection Table CLK 0 f CLK /f 0 RATIO MAX260/MAX261 MODES 1,3,4 MODE 2 100.53 71.09 102.10 72.20 103.67 73.31 105.24 74.42 106.81 75.53 108.38 76.64 109.96 77.75 111.53 78.86 113.10 79.97 114.67 81.08 116.24 ...

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Microprocessor Programmable Universal Active Filters Table Program Selection Table (continued) CLK 0 f CLK /f 0 RATIO MAX260/MAX261 MODES 1,3,4 MODE 2 172.79 122.18 174.36 123.29 175.93 124.40 177.50 125.51 179.07 126.62 180.64 127.73 182.21 128.84 183.78 ...

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Table 3. Q Program Selection Table PROGRAMMED Q PROGRAM CODE MODES MODE 1,3,4 2 0.500* 0.707 0.504 0.713 0.508 0.718 0.512 0.724 0.516 ...

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Microprocessor Programmable Universal Active Filters Table 3. Q Program Selection Table (continued) PROGRAMMED Q PROGRAM CODE MODES MODE 1,3,4 2 0.800 1. 0.810 1. 0.821 1.16 50 ...

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FILTER A OSC CLK A OUT 11 19(18)* CRYSTAL *OSC OUT IS PIN 18 ON MAX261/MAX262 FILTER A OSC CLK A OUT 19(18 FILTER A OSC CLK A OUT 11 N.C. EXTERNAL CLOCK IN (ANY DUTY CYCLE) ...

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Microprocessor Programmable Universal Active Filters OCTAL D FLIP-FLOP 74HC374 ...

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MODE 2 N SCN - IN - Σ SCN + + - SCN SCN Figure 8. Filter Mode 2: Second-Order Bandpass, Lowpass, and Notch MODE 3 HP SCN - IN - Σ SCN + + - SCN SCN SCN = ...

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Microprocessor Programmable Universal Active Filters MODE 4 SCN - IN - SCN Σ SCN SCN = SWITCHED-CAPACITOR NETWORK Figure 11. Filter Mode 4: Second-Order Bandpass, Lowpass, and Allpass Description of Filter Functions BANDPASS (Figure 12) For all ...

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LOWPASS OUTPUT OLP 0.707 H OLP f P f(LOG SCALE)     + −      − ...

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Microprocessor Programmable Universal Active Filters can also perform this last step. The desired f are stated, and the appropriate digital coefficients are supplied. Cascading Filters In some designs, such as very narrow band filters, sev- eral second-order sections with identical ...

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CMOS WR LOGIC A0–A3 LEVELS D0, D1 MAX260 MAX261 MAX262 Figure 16. Power Supply and Input Connections for Single Supply Operation mode 1 the maximum signal is 0 times the input signal, the input should not exceed ±(2/Q)V, or ±1V ...

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Microprocessor Programmable Universal Active Filters errors are predictable, the graphs can be used to cor- rect the selected f and Q so that the actual realized 0 parameters are on target. These predicted errors are not unique to MAX260 series ...

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When the outputs are used, the offset can be removed with capacitor coupling. Design Examples Fourth-Order Chebyshev Bandpass Filter Figure 22 shows both halves of a MAX260 ...

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Microprocessor Programmable Universal Active Filters 40 GAIN 15 -10 PHASE -35 -60 200 500 FREQUENCY (Hz MAX260 CLK CLK WR, AX ...

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PHASE -50 -70 100 200 500 1K 2K FREQUENCY (Hz MAX260 CLK CLK WR, AX PROGRAM CLK CLK MODE MODE f ...

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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 26 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2002 Maxim Integrated Products ...