MAX7427 Maxim Integrated Products, MAX7427 Datasheet
MAX7427
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MAX7427 Summary of contents
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... General Description The MAX7426/MAX7427 5th-order, lowpass, elliptic, switched-capacitor filters (SCFs) operate from a single +5V (MAX7426) or +3V (MAX7427) supply. The devices draw only 0.8mA of supply current and allow corner fre- quencies from 1Hz to 12kHz, making them ideal for low-power post-DAC filtering and anti-aliasing applica- tions. They can be put into a low-power mode, reducing supply current to 0.2µ ...
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Lowpass, Elliptic, Switched-Capacitor Filters ABSOLUTE MAXIMUM RATINGS V to GND ..............................................................-0.3V to +6V DD IN, OUT, COM, OS, CLK, SHDN ................-0. OUT Short-Circuit Duration.......................................................1s Continuous Power Dissipation (T = +70°C) A 8-Pin µMAX (derate 4.1mW/°C above +70°C) ...
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... Supply Voltage V Supply Current Shutdown Current I SHDN Power-Supply Rejection Ratio PSRR SHUTDOWN SHDN Input High V SHDN Input Low V SHDN Input Leakage Current ELECTRICAL CHARACTERISTICS—MAX7427 (V = +3V, filter output measured at OUT pin, 10kΩ DD GND 100kHz CLK A MIN MAX PARAMETER SYMBOL FILTER CHARACTERISTICS ...
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... DD Shutdown Current I SHDN Power-Supply Rejection Ratio PSRR SHUTDOWN SHDN Input High V SDH SHDN Input Low V SDL SHDN Input Leakage Current ELLIPTIC FILTER CHARACTERISTICS (r = 1.25 +5V for MAX7426 +3V for MAX7427, filter output measured at OUT, 10kΩ 100kHz, T COM OS DD CLK PARAMETER f = 0.38f 0.68f ...
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... MAX7426 +3V for MAX7427 wise noted.) FREQUENCY RESPONSE 1kHz 1.25 -10 -20 -30 -40 -50 -60 - INPUT FREQUENCY (kHz) SUPPLY CURRENT vs. SUPPLY VOLTAGE 0.82 0.80 0.78 0.76 0.74 0.72 0.70 2.5 3.0 3.5 4.0 4.5 SUPPLY VOLTAGE (V) _______________________________________________________________________________________ 5th-Order, Lowpass, Elliptic, Switched-Capacitor Filters ...
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... Lowpass, Elliptic, Switched-Capacitor Filters (V = +5V for MAX7426 +3V for MAX7427 wise noted.) MAX7426 TOTAL HARMONIC DISTORTION PLUS NOISE vs. INPUT SIGNAL AMPLITUDE 0 SEE TABLE 1. -10 -20 -30 -40 -50 -60 -70 B - AMPLITUDE (Vp-p) Table 1. THD + Noise Test Conditions LABEL _______________________________________________________________________________________ Typical Operating Characteristics (continued) ...
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... MAX7426 +3V for MAX7427 wise noted.) INTERNAL OSCILLATOR PERIOD vs. SMALL CAPACITANCE (IN pF) 200 V DD 150 100 500 1000 1500 2000 CAPACITANCE (pF) INTERNAL OSCILLATOR FREQUENCY vs. SUPPLY VOLTAGE 17.5 17.4 17.3 17 1000pF OSC 17.1 2.0 2.5 3.0 3.5 4.0 SUPPLY VOLTAGE (V) DC OFFSET VOLTAGE vs ...
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... IN Filter Input 3 GND Ground 4 V Positive Supply Input, +5V for MAX7426 or +3V for MAX7427 DD 5 OUT Filter Output Offset Adjust Input. To adjust output offset, bias OS with a resistive voltage-divider between an external 6 OS supply and ground. Connect OS to COM if no offset adjustment is needed. ...
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... Figure 3. Offset Adjustment Circuit Estimate the input impedance of the filter by using the following formula: where f CLK Internal Clock The MAX7426/MAX7427 have a shutdown mode that is activated by driving SHDN low. In shutdown mode, the 3 × 10 filter supply current reduces to 0.2µA, and the output of (pF) the filter becomes high impedance ...
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... MAX7427 100 10 ______________________________________________________________________________________ For either single-supply or dual-supply operation, drive CLK and SHDN from GND (V- in dual-supply operation Use the MAX7427 for ±2.5, and use the DD MAX7426 for ±1.5V. For ±5V dual-supply applications, refer to the MAX291/MAX292/MAX295/MAX296 and * MAX293/MAX294/MAX297 data sheets. OUTPUT The optimal input signal range is determined by observ- ...
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Information ______________________________________________________________________________________ 5th-Order, Lowpass, Elliptic, Switched-Capacitor Filters 11 ...
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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. 12 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2000 Maxim Integrated Products ...