MAX1945SEUI Maxim Integrated Products, MAX1945SEUI Datasheet
MAX1945SEUI
Specifications of MAX1945SEUI
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MAX1945SEUI Summary of contents
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... Adjustable Output from 0.8V to 85% of Input ♦ Voltage Margining: ±4% (MAX1945R) or ±9% (MAX1945S) ♦ Synchronize to External Clock ♦ SYNCOUT Provides 180-Degree Out-of-Phase Clock Output ♦ All-Ceramic or Electrolytic Capacitor Designs PART MAX1945REUI MAX1945SEUI Applications *EP = Exposed pad. INPUT 2.6V TO 5.5V MARGINING SYNCHRONIZATION CLOCK Features ...
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Accurate, 6A Internal Switch Step-Down Regulators ABSOLUTE MAXIMUM RATINGS CTL1, CTL2, IN, SYNC GND ...............-0. SYNCOUT, COMP, FB, FBSEL, REF to GND ............................................-0. Current (Note 1) .....................................................-9A ...
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Accurate, 6A Internal Switch ELECTRICAL CHARACTERISTICS (continued 3.3V, SYNC = GND, FBSEL = High- CTL1 CTL2 DD otherwise noted. Typical values are at +25°C.) PARAMETER ...
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Accurate, 6A Internal Switch Step-Down Regulators ELECTRICAL CHARACTERISTICS (continued 3.3V, SYNC = GND, FBSEL = High- CTL1 CTL2 DD otherwise noted. Typical values are at ...
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Accurate, 6A Internal Switch ELECTRICAL CHARACTERISTICS (continued 3.3V, SYNC = GND, FBSEL = High- CTL1 CTL2 DD otherwise noted. Typical values are at +25°C.) PARAMETER ...
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Accurate, 6A Internal Switch Step-Down Regulators ELECTRICAL CHARACTERISTICS (continued 3.3V, SYNC = GND, FBSEL = High- CTL1 CTL2 DD otherwise noted.) (Note 2) PARAMETER SYMBOL ...
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Accurate, 6A Internal Switch ELECTRICAL CHARACTERISTICS (continued 3.3V, SYNC = GND, FBSEL = High- CTL1 CTL2 DD otherwise noted.) (Note 2) PARAMETER SYMBOL LX Minimum ...
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Accurate, 6A Internal Switch Step-Down Regulators ( 5V 1.8V 6A OUT OUT EFFICIENCY vs. OUTPUT CURRENT 100 ...
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Accurate, 6A Internal Switch ( 5V 1.8V 6A OUT OUT PGND-MEASURED TEMPERATURE vs. OUTPUT CURRENT 140 120 AMBIENT TEMP: +85°C 100 AMBIENT TEMP: 80 +25° ...
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Accurate, 6A Internal Switch Step-Down Regulators ( 5V 1.8V 6A OUT OUT VOLTAGE MARGINING (9%) MAX1945 toc18 V CTL1 2V/div V OUT 200mV/div 400µs/div PIN NAME Bootstrap Voltage. ...
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Accurate, 6A Internal Switch PIN NAME 19, 21, 23, Power Ground. Connect all PGND together close to the device. Star connect GND to PGND (see the PC PGND 25 Board Layout Considerations section). Output Margining Control Inputs. When ...
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Accurate, 6A Internal Switch Step-Down Regulators The MAX1945R/MAX1945S employs digital soft-start to reduce supply in-rush current during startup conditions. When the device exits undervoltage lockout (UVLO), shutdown mode, or restarts following a thermal-overload event, the digital soft-start circuitry ...
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Accurate, 6A Internal Switch Use a low-loss inductor with the lowest possible DC resistance that fits in the allotted dimensions. Ferrite core types are often the best choice for performance. With any core material the core must be ...
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Accurate, 6A Internal Switch Step-Down Regulators Compensation Design The double pole formed by the inductor and the output capacitor of most voltage-mode controllers introduces a large phase shift, which requires an elaborate com- pensation network to stabilize the ...
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Accurate, 6A Internal Switch Set the error-amplifier compensation zero formed by R and C equal to the load-impedance pole frequency maximum load. Calculate C PLOAD ✕ OUT OUT The ...
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Accurate, 6A Internal Switch Step-Down Regulators Table 3. Compensation Values for Output Voltages (1MHz) VOUT (V) 0.8 R (1%) 100kΩ (10%) 330pF C mum zero-crossing frequency should be less than one- third of the load-impedance zero ...
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Accurate, 6A Internal Switch fz = [1/(2π ✕ [1/(2 ESR OUT ESR 0.005)] = 339kHz. For a 0.68µH output inductor, choose the closed-loop unity-gain crossover frequency (f Determine the switching regulator DC gain: G ...
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Accurate, 6A Internal Switch Step-Down Regulators IN BST SYNCOUT AC DETECT SYNC CTL1 CONTROL CTL2 V CC REFERENCE GND COMP FB FB FBSEL Pin Configuration TOP VIEW BST ...
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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. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 19 © 2004 Maxim Integrated Products ...