MAX8643AETG+ Maxim Integrated Products, MAX8643AETG+ Datasheet
MAX8643AETG+
Specifications of MAX8643AETG+
Related parts for MAX8643AETG+
MAX8643AETG+ Summary of contents
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... Base-Station Power Supplies Telecom and Networking Power Supplies RAID Control Power Supplies Pin Configuration appears at end of data sheet. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim's website at www.maxim-ic.com. 3A, 2MHz Step-Down Regulator with Integrated Switches o Internal 37mΩ ...
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Step-Down Regulator with Integrated Switches ABSOLUTE MAXIMUM RATINGS IN PWRGD to GND ......................................-0.3V to +4.5V DD COMP, FB, REFIN, OUT, CTL_, EN, SS, FREQ to GND...................-0. Current (Note 1) .....................................................-4A to +4A BST ...
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ELECTRICAL CHARACTERISTICS (continued 3.3V 0.5V -40°C to +85°C. Typical values are PARAMETER Open-Loop Voltage Gain 1kΩ from COMP to GND Error-Amplifier Unity-Gain Parallel 10kΩ, 40pF from ...
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Step-Down Regulator with Integrated Switches ELECTRICAL CHARACTERISTICS (continued 3.3V 0.5V -40°C to +85°C. Typical values are PARAMETER ENABLE EN Input Logic-Low, Falling EN Input ...
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3.3V EFFICIENCY vs. OUTPUT CURRENT 100 1.8V OUT 1.5V OUT 1.2V 70 OUT ...
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Step-Down Regulator with Integrated Switches (Typical values are 3.3V INPUT CURRENT vs. INPUT VOLTAGE 2.2 ...
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PIN NAME Leave pin unconnected to prevent discharging of output capacitor during soft-start. Connect to GND 1 PREBIAS otherwise. (See the Soft-Starting into a Prebiased Output section.) Supply Voltage and Bypass Input. Connect capacitor from V ...
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Step-Down Regulator with Integrated Switches SHUTDOWN EN CONTROL BIAS GENERATOR VOLTAGE REFERENCE SS SOFT-START REFIN OUT 8kΩ FB CTL1 VID VOLTAGE- CONTROL CTL2 CIRCUITRY COMP COMP LOW DETECTOR 8 _______________________________________________________________________________________ V DD UVLO CIRCUITRY CURRENT-LIMIT COMPARATOR CONTROL LOGIC ...
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INPUT 2. 22µF 0.1µF R1 10Ω 1µF R2 10kΩ C6 0.01µF C8 6800pF Figure 1. 1MHz, All-Ceramic Capacitor Design with V Detailed Description The MAX8643A high-efficiency, voltage-mode switch- ing regulator is capable of ...
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Step-Down Regulator with Integrated Switches The internal, high-side MOSFET has a typical 5.5A peak current-limit threshold. When current flowing out of LX exceeds this limit, the high-side MOSFET turns off and the synchronous rectifier turns on. The synchro- ...
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The logic states of CTL1 and CTL2 should be pro- grammed only before power-up. Once the part is enabled, CTL1 and CTL2 should not be changed. If the output voltage needs to be reprogrammed, cycle power or EN and reprogram ...
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Step-Down Regulator with Integrated Switches Input-Capacitor Selection The input capacitor reduces the current peaks drawn from the input power supply and reduces switching noise in the IC. The total input capacitance must be equal to or greater than ...
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COMPENSATION TRANSFER FUNCTION DOUBLE POLE GAIN (dB) POWER-STAGE TRANSFER FUNCTION FIRST AND SECOND ZEROS Figure 4. Type III Compensation Illustration π ...
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Step-Down Regulator with Integrated Switches where C is the output capacitor age the soft-start time set by the soft-start capacitor and I is the peak-to-peak inductor ripple current SS P-P (as ...
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Chip Information PROCESS: BiCMOS ______________________________________________________________________________________ 3A, 2MHz Step-Down Regulator with Integrated Switches For the latest package outline information and land patterns www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package ...
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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. 16 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2009 Maxim Integrated Products ...