max5951etjt Maxim Integrated Products, Inc., max5951etjt Datasheet
max5951etjt
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max5951etjt Summary of contents
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Rev 0; 5/06 12V/5V Input Buck PWM Controller General Description The MAX5951 is a 12V pulse-width modulated (PWM), step-down, DC-DC controller. The device operates over the input-voltage range 16V or 5V ±10%, and provides an adjustable ...
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Input Buck PWM Controller ABSOLUTE MAXIMUM RATINGS IN to AGND.............................................................-0.3V to +24V BST to AGND..........................................................-0.3V to +30V BST to LX..................................................................-0.3V to +6V CS- to AGND ...............................................-0. REG, DREG, PUVLO, DCENI, SYNCIN, THRESH, SENSE to AGND....................................................-0.3V to +6V ...
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Input Buck PWM Controller ELECTRICAL CHARACTERISTICS (continued 12V 5V REG DREG -40°C to +85°C, unless otherwise noted. Typical values are at T PARAMETER SYMBOL PWM PGOOD OUTPUT SENSE Threshold ...
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Input Buck PWM Controller ELECTRICAL CHARACTERISTICS (continued 12V 5V REG DREG -40°C to +85°C, unless otherwise noted. Typical values are at T PARAMETER SYMBOL PWM COMPARATOR Comparator Offset Voltage ...
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Input Buck PWM Controller ELECTRICAL CHARACTERISTICS (continued 12V 5V REG DREG -40°C to +85°C, unless otherwise noted. Typical values are at T PARAMETER SYMBOL PWM DL DRIVER Peak Source ...
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Input Buck PWM Controller (Typical Operating Circuits 12V 2.2µ +25°C.) REG A REG OUTPUT VOLTAGE vs. LOAD CURRENT 5.15 5.10 5.05 5.00 4.95 4.90 4. ...
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Input Buck PWM Controller (Typical Operating Circuits 12V 2.2µ +25°C.) REG A DL, DH DRIVER ON-RESISTANCE vs. TEMPERATURE 2. 0.9V FB 1.75 1.50 1.25 RESISTANCE SOURCING 1.00 RESISTANCE ...
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Input Buck PWM Controller (Typical Operating Circuits 12V 2.2µ +25°C.) REG A OVERLOAD RESPONSE (HICCUP MODE) 400µs/div SHORT-CIRCUIT RESPONSE (HICCUP MODE) 400µs/div BREAK-BEFORE-MAKE TIME 10ns/div 8 _______________________________________________________________________________________ Typical Operating Characteristics ...
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Input Buck PWM Controller (Typical Operating Circuits 12V 2.2µ +25°C.) REG A EFFICIENCY vs. LOAD CURRENT 100 PWM_IN V = 12V PWM_IN 50 ...
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Input Buck PWM Controller PIN NAME Supply Input Connection. Connect to an external voltage source from 8V to 16V. For 5V input application, connect IN = REG ±10% source. Connect an external divider ...
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Input Buck PWM Controller PIN NAME Positive Current-Sense Input. Connect CS+ to the synchronous MOSFET source (connected to 24 CS+ PGND). 25 CS- Negative Current-Sense Input. Connect CS- to the synchronous MOSFET drain (connected to LX). Power-Ground Connection. Connect ...
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Input Buck PWM Controller Internal Linear Regulator (REG) REG is the output terminal LDO, which is pow- ered from IN and provides power to the IC. Bypass REG to AGND with a 2.2µF ceramic capacitor. Place ...
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Input Buck PWM Controller TRACKING DCEN1 THRESH1 PGOOD1 DCENI2 THRESH2 PGOOD2 DCENI3 THRESH3 PGOOD3 STARTUP1 STARTUP2 STARTUP3 Figure 1. Tracking, STARTUP Sequencing, and PGOOD Sequencing Configurations ______________________________________________________________________________________ STARTUP SEQUENCING DCENI1 REG1 THRESH1 THRESH1 PGOOD1 PGOOD1 DCENI2 DCENI2 THRESH2 REG2 ...
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Input Buck PWM Controller The output of the internal error amplifier (COMP) is available for frequency compensation (see the Compensation Design Guidelines section). The invert- ing input is FB; the output is COMP. The error amplifier has an 80dB ...
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Input Buck PWM Controller Setting the Output Voltage Connect a resistive divider from OUT AGND to set the output voltage. First, calculate the resistor from OUT to FB using the guidelines in the Compensation Design Guidelines ...
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Input Buck PWM Controller The allowable deviation of the output voltage during load transients also affects the choice of capacitance, its ESR, and its equivalent series inductance (ESL). The output capacitor supplies the load current during a load step ...
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Input Buck PWM Controller Compensation Design Guidelines The MAX5951 uses a voltage-mode control scheme that regulates the output voltage by comparing the error amplifier output (COMP) with an internal ramp to produce the required duty cycle. The output lowpass ...
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Input Buck PWM Controller Compensation when f Figure 5 shows the error-amplifier feedback, as well as its gain response for circuits that use low-ESR output capacitors (ceramic). In this case ZESR f is set to 0.5 ...
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Input Buck PWM Controller PWM Controller Applications Information Power Dissipation The 32-pin TQFN thermally enhanced package can dis- sipate 2.7W. Calculate power dissipation in the MAX5951 as a product of the input voltage and the total REG output current ...
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Input Buck PWM Controller PWM_IN PUVLO LDO REG EN 0.8V THERMAL REF SHDN RES REF DIGITAL CLK SOFT-START FB COMP EN SYNCIN RAMP RT OSC SYNCOUT 20 ______________________________________________________________________________________ PWM CONTROLLER THRESH 1.220V VREGOK E/A CPWM IMAX REF 0.3V CLK ...
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Input Buck PWM Controller +12V REG PUVLO MAX5951 THRESH SYNCIN SYNCOUT RT DCENI AGND PGOOD REG PUVLO MAX5951 THRESH RT DCENI AGND PGOOD SYNCIN SYNCOUT R RT ______________________________________________________________________________________ Typical Operating Circuits TRACKING C ...
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Input Buck PWM Controller +12V PUVLO THRESH DCENI AGND PGOOD IN PUVLO THRESH DCENI AGND PGOOD 22 ______________________________________________________________________________________ Typical Operating Circuits (continued) STARTUP SEQUENCING BST DREG REG MAX5951 SYNCIN SYNCOUT RT ILIM STARTUP COMP R R ...
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Input Buck PWM Controller +12V REG PUVLO MAX5951 THRESH DCENI AGND PGOOD SYNCIN SYNCOUT REG MAX5951 THRESH PUVLO DCENI AGND PGOOD SYNCIN SYNCOUT ______________________________________________________________________________________ Typical Operating Circuits (continued) PGOOD ...
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Input Buck PWM Controller +12V REG PUVLO THRESH DCENI AGND PGOOD SYNCIN 24 ______________________________________________________________________________________ Typical Operating Circuits (continued) ALTERNATE CURRENT SENSE DREG BST DH CS- MAX5951 CS+ PGND SENSE SYNCOUT RT ILIM STARTUP COMP R RT ...
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... T2855 T2855-8 WHHC WHHD-1 WHHD-2 ----- T2855N-1 T3255-3 T3255-4 T3255-5 T3255N-1 3.00 T4055-1 Printed USA is a registered trademark of Maxim Integrated Products, Inc. Package Information PIN # 1 I.D. e/2 0.35x45° e (ND- DETAIL PACKAGE OUTLINE, 16, 20, 28, 32, 40L THIN QFN, 5x5x0 ...