max253cuat Maxim Integrated Products, Inc., max253cuat Datasheet
max253cuat
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max253cuat Summary of contents
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Rev 0; 1/94 _______________General Description The MAX253 is a monolithic oscillator/power-driver, specifically designed to provide isolated power for an isolated RS-485 or RS-232 data interface. drives a center-tapped transformer primary from 3.3V DC power supply. The ...
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Transformer Driver for Isolated RS-485 Interface ABSOLUTE MAXIMUM RATINGS Supply Voltage (V ) ...............................................-0.3V to +7V CC Control Input Voltages (SD, FS) .................-0. Output Switch Voltage (D1, D2) .............................................12V Peak Output Switch Current (D1, D2) ......................................1A Average Output ...
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Operating Characteristics (Circuit of Figure ±10 +25°C, unless otherwise noted OUTPUT RESISTANCE vs. TEMPERATURE (FS = LOW) 10.5 MEASURED AT TP1 10.0 9 4.5V IN 9.0 8.5 8.0 V ...
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Transformer Driver for Isolated RS-485 Interface ____________________________Typical Operating Characteristics (continued) (Circuit of Figure ±10 +25°C, unless otherwise noted EFFICIENCY vs. LOAD CURRENT (FS = HIGH) 100 5. ...
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Description PIN NAME FUNCTION 1 D1 Open drain of N-channel transfomer drive 1. Ground. Connect both GND1 and GND2 2 GND1 to ground. Frequency switch switch frequency = 350kHz 0V, ...
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Transformer Driver for Isolated RS-485 Interface 0.1µ MAX253 ON / OFF GND1 GND2 74HC04 390 DI * 74HC04 390 DE 3.3k * 74HC04 RO * ...
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V IN 3.3V C1 0.1µ N.C. 4 MAX253 ON / OFF GND1 GND2 2 7 1N5817 C5 0.1µF * 74HC04 390 DI * 74HC04 390 DE 3.3k * 74HC04 ...
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Transformer Driver for Isolated RS-485 Interface 0.1µ N.C. MAX253 OFF SD GND1 GND2 2 *74HC04 390 T1 IN 74HC04 390 T2 IN 74HC04 390 T3 IN 74HC04 390 T4 IN ...
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Information Figures 3–5 are typical isolated RS-485/RS-232 data-inter- face circuits. These circuits withstand 1800V and are intended for industrial communications and control applications where very high voltage transients, differential ground potentials, or high noise may be encountered. Table 2 ...
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Transformer Driver for Isolated RS-485 Interface 0.1µ OFF 3 FS FREQUENCY SWITCH GND1 *SEE TABLE 2 Figure Isolated 5V Application Circuit V IN 3.3V C1 0.1µ ...
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MAX253 GND1 GND2 0.1V to 0.5V 6 MAX480 2 4 49.9k *SEE TABLE 2 Figure 8. Typical 4mA to 20mA Application Circuit Output-Ripple Filtering A ...
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Transformer Driver for Isolated RS-485 Interface V IN INPUT MAX253 8 D2 GND1 GND2 2 7 *SEE TABLE 2 Figure 9a. Half-Wave Rectifier—Bipolar V IN INPUT MAX253 8 D2 GND1 ...
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ISO 5V ISO -12V 10µF MAX176 0.1µ ANALOG AIN CONVST INPUT 3 6 VREF CLOCK 4 5 0.1µF GND DATA 10µF 0.1µF 10µF SIGNAL GROUND *SEE TABLE 2 Figure 10. ...
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Transformer Driver for Isolated RS-485 Interface sensor, an extra several hundred milliwatts could easily be supplied by the circuit, as shown. A +12V supply could be generated by adding two more diodes to the ends of the secondary, and a ...
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In addition, include in the calculations an allowance for worst-case losses in the rectifiers. Since the turns ratio determined in this manner will ordinarily produce a much higher voltage at the secondary under conditions of high input voltage and/or ...
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Transformer Driver for Isolated RS-485 Interface ___________________Chip Topography D1 D2 GND1 FS SD 0.058" (1.4732mm) TRANSISTOR COUNT: 31; SUBSTRATE CONNECTED ________________________________________________________Package Information Maxim cannot assume responsibility for use of ...