MAX8550AETI+ Maxim Integrated Products, MAX8550AETI+ Datasheet
MAX8550AETI+
Specifications of MAX8550AETI+
Related parts for MAX8550AETI+
MAX8550AETI+ Summary of contents
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... Power-Good Window Comparator REFIN PART MAX8550AETI TOP VIEW OVP/UVP Applications Typical Operating Circuit appears at end of data sheet. Quick-PWM is a trademark of Maxim Integrated Products, Inc. Features / 2 REFIN Ordering Information TEMP RANGE PIN-PACKAGE 28 TQFN 5mm × 5mm -40°C to +85°C Pin Configuration ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards ABSOLUTE MAXIMUM RATINGS V to GND .............................................................-0.3V to +30V VTTI to GND .........................................-0.3V to +6V DD, DD SHDN, REFIN to GND ..............................................-0.3V to +6V SS, POK1, ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards ELECTRICAL CHARACTERISTICS (continued) = STBY = +15V SHDN GND, PGND1 = PGND2 = LX = GND, TON = ...
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... Input Bias Current (FB) Four-Level Input Logic Levels (TON, OVP/UVP) Logic Input Current (TON, OVP/UVP) OUT Input Resistance OUT Discharge-Mode On-Resistance DL Turn-On Level During Discharge Mode (Measured at OUT) Dual Mode is a trademark of Maxim Integrated Products, Inc. 4 _______________________________________________________________________________________ = BST ILIM OUT REFIN ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards ELECTRICAL CHARACTERISTICS (continued) = STBY = +15V SHDN GND, PGND1 = PGND2 = LX = GND, TON = ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards = 2.5V, TON = GND, SKIP = 12V, V VIN OUT EFFICIENCY vs. LOAD CURRENT (TON = GND) 100 f = 600kHz ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards = 2.5V, TON = GND, SKIP = 12V, V VIN OUT LOAD TRANSIENT (BUCK) MAX8550A toc10 I = 1.5A 15mA VTT VTTR V OUT 100mV/div ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards = 2.5V, TON = GND, SKIP = 12V, V VIN OUT STANDBY RESPONSE, VTT AT NO LOAD 5V/div 500mV/div 500mV/div 500mV/div 2ms/div SHORT CIRCUIT AND RECOVERY OF ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards PIN NAME On-Time Selection-Control Input. This four-level logic input sets the nominal DH on-time. Connect to GND, REF, AV TON = AV (200kHz TON TON = OPEN (300kHz) ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards PIN NAME 11 PGND2 Power Ground for VTT and VTTR. Connect PGND2 externally to the underside of the exposed pad. 12 VTT Termination Power-Supply Output. Connect VTT to VTTS to ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards TON OVP/UVP BUCK ON/OFF SHDN BIAS ON/OFF SHUTDOWN TP0 DECODER STBY VTT ON/OFF VTTR ON/OFF INTREF + 10% POK1 N FB REFIN / 2 - 10% POK2 N REFIN / ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards Detailed Description The MAX8550A combines a synchronous-buck PWM con- troller, an LDO linear regulator, and a 10mA reference out- put buffer. The buck controller drives two external n-channel MOSFETs to ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards The on-time one-shot has good accuracy at the operat- ing points specified in the Electrical Characteristics table (approximately ±12.5% at 600kHz and 450kHz, and ±10% at 200kHz and 300kHz). On-times ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards tance remains fixed) and less output voltage ripple. Penalties for using higher inductor values include larger physical size and degraded load-transient response, especially at low input-voltage levels. DC output accuracy ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards TO PWM CONTROLLER (SEE FIGURE 1) Figure 3. Adjustable Current-Limit Threshold I LOAD(MAX) I LIM(VAL TIME Figure 4. Valley Current-Limit Threshold (UVLO) circuitry inhibits switching. The controller inhibits ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards Power-OK (POK1) POK1 is an open-drain output for a window comparator that continuously monitors V . POK1 is actively held OUT low when SHDN is low and during the buck ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards Overvoltage Protection (OVP) When the output voltage rises above 116% of the nomi- nal regulation voltage and OVP is enabled (OVP/UVP = AV or open), the OVP circuit sets the ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards • Maximum Load Current. There are two values to con- sider. The peak load current (I PEAK instantaneous component stresses and filtering requirements and thus drives output capacitor selec- tion, ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards LX MAX8550A DL Q2 PGND1 GND OUT FB Figure 6. Setting V OUT with a Resistive Voltage-Divider Find a low-loss inductor with the lowest possible DC resistance that fits in ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards Stability Requirements For Quick-PWM controllers, stability is determined by the value of the ESR zero relative to the switching fre- quency. The boundary of instability is given by the fol- ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards capacitor. Nevertheless, a ceramic capacitor of at least 10µF must be used and must be added and placed as close as possible to the VTTI pin. This value must be ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards where 5V. In addition to the losses above allow about 20% more for additional losses because of MOSFET output capacitances and low-side MOSFET body-diode ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards used for setting the adjustable current limit as shown in Figure 7. The following is a procedure for calculating the value of R4, R5, and R6: 1) Calculate the voltage, ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards VTTI C2 10μF VTT VTT 1.25V / ±1.5A C4 VTTS 60μF PGND2 VTTR VTTR 1.25V / 10mA C6 1μF OVP/UVP R2 R3 100kΩ 100kΩ POK1 POK POK2 SKIP TON GND ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards The overshoot during a full-load to no-load transient due to stored inductor energy can be calculated as: Δ I LOAD MAX ( = V SOAR × × OUT ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards AV DD MAX8550A FB Figure 9. Voltage-Positioned Output thick copper PC boards (2oz vs. 1oz) can enhance full-load efficiency more. Correctly routing PC board traces is a ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards VTTI C2 VTT VTT 0.9V - 1.25V / 1.5A C4 VTTS PGND2 VTTR VTTR 0.9V - 1.25V / 10mA C6 OVP/UVP R2 R3 POK1 POK POK2 SKIP TON GND C9 ...
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Integrated DDR Power-Supply Solution for Desktops, Notebooks, and Graphic Cards (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) 28 ______________________________________________________________________________________ Package Information ...
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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 ____________________ 29 © 2004 Maxim Integrated Products ...