MAX1858AEEG+ Maxim Integrated Products, MAX1858AEEG+ Datasheet
MAX1858AEEG+
Specifications of MAX1858AEEG+
Related parts for MAX1858AEEG+
MAX1858AEEG+ Summary of contents
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... DSP, ASIC, and FPGA Power Supplies Set-Top Boxes Broadband Routers Servers Desknote Computers ________________________________________________________________ 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. ♦ 4.5V to 23V Input Supply Range ♦ 18V Output Voltage Range (Up to 10A) ♦ ...
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Dual 180° Out-of-Phase Buck Controllers with Sequencing/Prebias Startup and POR ABSOLUTE MAXIMUM RATINGS V+ to GND ..............................................................-0.3V to +25V PGND to GND .......................................................-0.3V to +0. GND ..................-0.3V to the lower of +6V and (V+ + 0.3V) L BST1, ...
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Dual 180° Out-of-Phase Buck Controllers with Sequencing/Prebias Startup and POR ELECTRICAL CHARACTERISTICS (continued) (V+ = 12V ILIM_ = V , SYNC = GND compensation components for COMP_ are from Figure 1, T PARAMETER Switching frequency must ...
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Dual 180° Out-of-Phase Buck Controllers with Sequencing/Prebias Startup and POR (Circuit of Figure 12V +25°C, unless otherwise noted EFFICIENCY vs. LOAD 100 90 OUT2 80 OUT1 ...
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Dual 180° Out-of-Phase Buck Controllers with Sequencing/Prebias Startup and POR (Circuit of Figure 12V +25°C, unless otherwise noted START AND STOP WAVEFORM (MAX1875A/MAX1876A ONLY) MAX1858A/75A/76A toc09 10V OUT1 1V/div I ...
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Dual 180° Out-of-Phase Buck Controllers with Sequencing/Prebias Startup and POR PIN NAME Compensation Pin for Regulator 2 (REG2). Compensate REG2’s control loop by connecting a series resistor 1 COMP2 (R ) and capacitor (C COMP2 shown in Figure 1. Feedback ...
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Dual 180° Out-of-Phase Buck Controllers with Sequencing/Prebias Startup and POR PIN NAME 14 DH1 High-Side Gate-Driver Output for Regulator 1 (REG1). DH1 swings from LX1 to BST1. DH1 is low during UVLO. External Inductor Connection for Regulator 1 (REG1). Connect ...
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Dual 180° Out-of-Phase Buck Controllers with Sequencing/Prebias Startup and POR 23V R V+ 4.7Ω 0.22µF C IN1 2 × 10µF N OUTPUT1 H1 1.8V OUT 1.1µH C OUT1 4 × 220µF ...
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Dual 180° Out-of-Phase Buck Controllers with Sequencing/Prebias Startup and POR REF GND COMP1 FB1 SOFT-START DAC (SEQUENCING— MAX1858A ONLY) 1V P-P OSC SYNC OSCILLATOR CK0 RST (MAX1858A/ MAX1876A ONLY) RESET EN UVLO V REF AND SHUTDOWN V L COMP2 FB2 ...
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Dual 180° Out-of-Phase Buck Controllers with Sequencing/Prebias Startup and POR UVLO VOUT_ SS_ DH_ DL_ MAX1875A/MAX1876A POWER-ON-OFF SEQUENCING DEFINITIONS SYMBOL UVLO Undervoltage lockout trip level is provided in the Electrical Characteristics table. VL Internal ...
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Dual 180° Out-of-Phase Buck Controllers with Sequencing/Prebias Startup and POR UVLO VOUT1 SS1 VOUT2 SS2 DH1 DL1 DH2 DL2 MAX1858A POWER-ON-OFF SEQUENCING DEFINITIONS SYMBOL DEFINITION Undervoltage threshold value is provided in the UVLO Electrical Characteristics ...
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Dual 180° Out-of-Phase Buck Controllers with Sequencing/Prebias Startup and POR High-Side Gate-Drive Supply (BST_) Gate-drive voltages for the high-side N-channel switch- es are generated by the flying-capacitor boost circuits (Figure 5). A boost capacitor (connected from BST_ to LX_) provides ...
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Dual 180° Out-of-Phase Buck Controllers with Sequencing/Prebias Startup and POR The adjustable current limit accommodates MOSFETs with a wide range of on-resistance characteristics (see the Design Procedure section). The current-limit thresh- old is adjusted with an external resistor at ILIM_ ...
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Dual 180° Out-of-Phase Buck Controllers with Sequencing/Prebias Startup and POR • SYNC Driven by External Oscillator: The controller generates the clock signal by dividing down the SYNC input signal, so that the switching frequency equals half the synchronization frequency (f ...
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Dual 180° Out-of-Phase Buck Controllers with Sequencing/Prebias Startup and POR Setting the Output Voltage For 1V or greater output voltages, set the MAX1858A/ MAX1875A/MAX1876A output voltage by connecting a voltage-divider from the output to FB_ to GND (Figure 8). Select ...
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Dual 180° Out-of-Phase Buck Controllers with Sequencing/Prebias Startup and POR inductor’s saturation rating must exceed the peak- inductor current at the maximum defined load current (I ): LOAD(MAX) LIR ⎛ ⎞ ⎜ ⎟ PEAK LOAD MAX ...
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Dual 180° Out-of-Phase Buck Controllers with Sequencing/Prebias Startup and POR The output voltage ripple as a consequence of the ESR and output capacitance is RIPPLE ESR ( ) P P ESR - ...
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Dual 180° Out-of-Phase Buck Controllers with Sequencing/Prebias Startup and POR At some higher frequency, the output capacitor’s impedance becomes insignificant compared to its ESR, and the LC system becomes more like an LR system, turning a double pole into a ...
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Dual 180° Out-of-Phase Buck Controllers with Sequencing/Prebias Startup and POR MOSFET Selection The MAX1858A/MAX1875A/MAX1876As’ step-down controller drives two external logic-level N-channel MOSFETs as the circuit switch elements. The key selection parameters are: • On-resistance (R ) DS(ON) • Maximum drain-to-source ...
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Dual 180° Out-of-Phase Buck Controllers with Sequencing/Prebias Startup and POR Applications Information Dropout Performance When working with low input voltages, the output-volt- age adjustable range for continuous-conduction opera- tion is restricted by the minimum off-time (t For best dropout performance, ...
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Dual 180° Out-of-Phase Buck Controllers with Sequencing/Prebias Startup and POR • Use a star-ground connection on the power plane to minimize the crosstalk between OUT1 and OUT2. • Keep the high-current paths short, especially at the ground terminals. This practice ...
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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. 22 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2003 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products ...