MAX8550ETI+T Maxim Integrated Products, MAX8550ETI+T Datasheet
MAX8550ETI+T
Specifications of MAX8550ETI+T
Related parts for MAX8550ETI+T
MAX8550ETI+T Summary of contents
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... MAX8550ETI+ MAX8551ETI +Denotes lead-free package. TOP VIEW OVP/UVP (N.C. FOR MAX8551) 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 5mm × 5mm TQFN -40°C to +85°C 28 5mm × 5mm TQFN -40° ...
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Integrated DDR Power-Supply Solutions 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 SHDNA, SHDNB, REFIN to GND..............................-0.3V to +6V SS, POK1, ...
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Integrated DDR Power-Supply Solutions for Desktops, Notebooks, and Graphic Cards ELECTRICAL CHARACTERISTICS (continued +15V SHDNA = GND, PGND1 = PGND2 = LX = GND, TON = OPEN, V ...
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... Input Bias Current (FB) Four-Level Input Logic Levels (TON, OVP/UVP (Note 4)) Logic Input Current (TON, OVP/UVP (Note 4)) 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 _______________________________________________________________________________________ SHDNB = 5V BST ILIM OUT ...
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Integrated DDR Power-Supply Solutions for Desktops, Notebooks, and Graphic Cards ELECTRICAL CHARACTERISTICS (continued +15V SHDNA = GND, PGND1 = PGND2 = LX = GND, TON = OPEN, V ...
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Integrated DDR Power-Supply Solutions 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 Solutions for Desktops, Notebooks, and Graphic Cards = 2.5V, TON = GND, SKIP = 12V, V VIN OUT LOAD TRANSIENT (BUCK) MAX8550/51 toc10 I = 1.5A 15mA VTT VTTR V OUT 100mV/div ...
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Integrated DDR Power-Supply Solutions for Desktops, Notebooks, and Graphic Cards = 2.5V, TON = GND, SKIP = 12V, V VIN OUT OVERVOLTAGE AND TURN-OFF OF BUCK OUTPUT 20µs/div SHORT CIRCUIT AND RECOVERY OF ...
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Integrated DDR Power-Supply Solutions 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 = TON TON = OPEN (300kHz) TON ...
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Integrated DDR Power-Supply Solutions 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 Solutions for Desktops, Notebooks, and Graphic Cards TON OVP/UVP QUAD LEVEL DECODE (N.C. IN MAX8551) BUCK ON/OFF SHDNA BIAS ON/OFF SHUTDOWN SHDNB DECODER STBY 0.7 x INTREF VTT ON/OFF VTTR ON/OFF INTREF + 10% POK1 N FB ...
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Integrated DDR Power-Supply Solutions for Desktops, Notebooks, and Graphic Cards Detailed Description The MAX8550/MAX8551 combine a synchronous-buck PWM controller, an LDO linear regulator, and a 10mA ref- erence output buffer. The buck controller drives two exter- nal N-channel MOSFETs to ...
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Integrated DDR Power-Supply Solutions for Desktops, Notebooks, and Graphic Cards 2) The inductor ripple-current operating point remains relatively constant, resulting in an easy design methodology and predictable output voltage ripple. The on-time one-shot has good accuracy at the operat- ing ...
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Integrated DDR Power-Supply Solutions for Desktops, Notebooks, and Graphic Cards light-load efficiency are made by varying the inductor value. Generally, low inductor values produce a broad- er efficiency vs. load curve, while higher values result in higher full-load efficiency (assuming ...
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Integrated DDR Power-Supply Solutions 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 POR, UVLO, and Soft-Start Internal power-on reset ...
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Integrated DDR Power-Supply Solutions for Desktops, Notebooks, and Graphic Cards attained when SS reaches approximately 1.6V. This lowering of the current limit during startup limits the ini- tial inrush current peaks, particularly when driving capacitors. Choose the value of the ...
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Integrated DDR Power-Supply Solutions for Desktops, Notebooks, and Graphic Cards Current Limit (LDO for VTT and VTTR Buffer) The VTT output is a linear regulator that regulates the input (VTTI) to half the V voltage. The feedback REFIN point for ...
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Integrated DDR Power-Supply Solutions for Desktops, Notebooks, and Graphic Cards shut off, go high impedance, and restart after the die portion of the IC cools by 15°C. Both thermal faults are independent. For example, if the VTT output is over- ...
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Integrated DDR Power-Supply Solutions for Desktops, Notebooks, and Graphic Cards LX MAX8550 MAX8551 PGND1 GND OUT FB Figure 6. Setting V OUT with a Resistive Voltage-Divider divider from VTT to VTTS. The maximum value for VTT is V ...
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Integrated DDR Power-Supply Solutions for Desktops, Notebooks, and Graphic Cards The actual capacitance value required relates to the physical size needed to achieve low ESR, as well as to the chemistry of the capacitor technology. Thus, the capacitor is usually ...
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Integrated DDR Power-Supply Solutions for Desktops, Notebooks, and Graphic Cards VTTR Output Capacitor Selection (LDO) The VTTR buffer is a scaled-down version of the VTT regulator, with much smaller output transconductance. Its compensation cap can therefore be smaller, and its ...
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Integrated DDR Power-Supply Solutions for Desktops, Notebooks, and Graphic Cards × I × f HSSW IN LOAD SW where I is the average DH-driver output current GATE determined by GATE ON ( ...
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Integrated DDR Power-Supply Solutions for Desktops, Notebooks, and Graphic Cards a divider current of approximately 10µA to prevent signifi- cant inaccuracy in the valley current-limit tolerance. Foldback Current Limit Alternately, foldback current limit can be implemented if the UVP latch ...
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Integrated DDR Power-Supply Solutions 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 POK POK1 POK2 SKIP TON GND ...
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Integrated DDR Power-Supply Solutions for Desktops, Notebooks, and Graphic Cards The output sag is also a function of the maximum duty factor, which can be calculated from the on-time and minimum off-time: ⎡ OUT L × ∆ I ...
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Integrated DDR Power-Supply Solutions for Desktops, Notebooks, and Graphic Cards AV DD MAX8550/ MAX8551 FB Figure 9. Voltage-Positioned Output PC Board Layout Guidelines Careful PC board layout is critical to achieve low switching losses and clean, stable operation. The switching ...
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Integrated DDR Power-Supply Solutions for Desktops, Notebooks, and Graphic Cards VTTI C2 VTT VTT 0.9V - 1.25V / 1.5A VTTS C4 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 Solutions 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 ...