MAX8720ETX+ Maxim Integrated Products, MAX8720ETX+ Datasheet
MAX8720ETX+
Specifications of MAX8720ETX+
Related parts for MAX8720ETX+
MAX8720ETX+ Summary of contents
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... QFN package. CPU Core Supply Converters GPU Core Supply Converters Notebook and Subnotebook Computers Quick-PWM is a trademark of Maxim Integrated Products, Inc. Pin Configurations appear at end of data sheet. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’ ...
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Dynamically Adjustable 6-Bit VID Step-Down Controller ABSOLUTE MAXIMUM RATINGS V to AGND............................................................-0. PGND............................................................-0.3V to +6V DD AGND to PGND .....................................................-0.3V to +0. PGND............................................................-0.3V to +30V SHDN to AGND ......................................................-0.3V to +16V D0–D5, PGOOD, ...
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ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 15V, SHDN = SKIP = V values are +25°C.) A PARAMETER SYMBOL Minimum Off-Time (Note 2) t OFF(MIN) BIAS AND REFERENCE Quiescent Supply Current ( Quiescent ...
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Dynamically Adjustable 6-Bit VID Step-Down Controller ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 15V, SHDN = SKIP = V values are +25°C.) A PARAMETER SYMBOL Current-Limit Threshold (Fixed) V Current-Limit Threshold V (Adjustable) Current-Limit Threshold ...
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ELECTRICAL CHARACTERISTICS (Circuit of Figure 1, V+ =15V, SHDN = SKIP = V Typical values are +25°C.) (Note 4) A PARAMETER SYMBOL PWM CONTROLLER Input Voltage Range DC Output Voltage Accuracy FB Input Resistance TIME Frequency Accuracy ...
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Dynamically Adjustable 6-Bit VID Step-Down Controller ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 1, V+ =15V, SHDN = SKIP = V Typical values are +25°C.) (Note 4) A PARAMETER SYMBOL Output Overvoltage Trip Threshold Output Undervoltage-Protection Trip Threshold ...
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Circuit of Figure 12V EFFICIENCY vs. LOAD CURRENT (V = 1.25V) OUT 100 12V 20V IN 60 SKIP = GND SKIP = ...
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Dynamically Adjustable 6-Bit VID Step-Down Controller (MAX8720 Circuit of Figure 12V STARTUP WAVEFORMS (NO LOAD) 1.25V -5A 500µs/div LOAD OUT 500mV/div C ...
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Circuit of Figure 12V DYNAMIC OUTPUT VOLTAGE TRANSITION (PWM MODE) 1.65V 1.25V 12V 0 0 10A 0 -10A 50µs/div SKIP = 0.2A CC OUT 200mV/div C ...
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Dynamically Adjustable 6-Bit VID Step-Down Controller PIN NAME 36 THIN 28 QSOP QFN SHDN TIME FBS S0 ...
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PIN NAME 36 THIN 28 QSOP QFN 13 11 GNDS 14 12 PGOOD 15 — GND 16 16 SUS SKIP ...
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Dynamically Adjustable 6-Bit VID Step-Down Controller (6) 100kΩ VID0 VID1 VID2 VID3 VID4 VID5 +5V BIAS R8 100kΩ PGOOD PWM ON Figure 1. MAX8720 Standard Application Circuit Detailed Description The MAX8720 is a constant-on-time, quick-PWM con- troller ...
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Table 1. Component Selection for Standard Applications COMPONENT Input Voltage 24V IN Output Voltage V = 1.25V OUT (2) 10µF, 25V TDK C3225X7R1E106M C Input Capacitor IN AVX 12103D106M Taiyo Yuden TMK325BJ106MM (3) 470µF, 2.5V, 9mΩ ...
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Dynamically Adjustable 6-Bit VID Step-Down Controller V BATT 2V TO 28V V+ TON ON-TIME FROM D/A COMPUTE TON TON TRIG Q ONE-SHOT SHDN REF 70kΩ GNDS FB FBS REF +15% REF -15% PGOOD ...
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With reversed inductor current, the inductor’s EMF causes high earlier than normal, extending the on-time by a period equal to the DH-rising dead ...
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Dynamically Adjustable 6-Bit VID Step-Down Controller threshold between pulse-skipping PFM and nonskip- ping PWM operation to coincide with the boundary between continuous and discontinuous inductor-cur- rent operation. The load-current level at which PFM/PWM crossover occurs, I LOAD(SKIP) half the peak-to-peak ...
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OUT = ∆ ON-TIME TIME Figure 3. Pulse-Skipping/Discontinuous Crossover Point C RSS > C ISS Lot-to-lot variation of the threshold voltage can cause ...
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Dynamically Adjustable 6-Bit VID Step-Down Controller MODE FORCED-PWM MODE SHDN PGOOD V CPU Figure 6. Soft-Startup and Soft-Shutdown Soft-Startup and Soft-Shutdown ( SHDN ) When SHDN goes low, the MAX8720 enters low-power shutdown mode. PGOOD goes low ...
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Table 4. Output Voltage vs. DAC Codes ...
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Dynamically Adjustable 6-Bit VID Step-Down Controller Table 5. Suspend-Mode DAC Codes OUT GND GND 0.650 OPEN GND REF 0.625 OPEN GND OPEN 0.600 OPEN GND V 0.575 OPEN CC REF GND 0.550 V CC REF REF ...
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HIGH VID VOLTAGE V OUT LOW VID VOLTAGE SKIP SUS PGOOD HIGH IMPEDANCE D0-D5 HIGH VID MODE PWM MODE FORCED-PWM Figure 8. VID Transition in Forced-PWM Mode ( HIGH VID VOLTAGE V OUT LOW VID VOLTAGE SKIP SUS PGOOD LOW ...
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Dynamically Adjustable 6-Bit VID Step-Down Controller D0–D5 VOLTAGE V OUT S0, S1 VOLTAGE SKIP SUS PGOOD HIGH IMPEDANCE TARGET D0–D5 MODE PWM MODE FORCED-PWM Figure 10. Suspend Transition in Forced-PWM Mode ( SKIP = High) D0–D5 VOLTAGE V OUT S0, ...
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Suspend Transition (Pulse-Skipping If the MAX8720 is configured for pulse-skipping opera- tion (SKIP = GND) when SUS goes high, the MAX8720 immediately enters forced-PWM mode, ramping the output voltage down to the S0, S1 programmed voltage at the slew rate ...
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Dynamically Adjustable 6-Bit VID Step-Down Controller value also determines the load-current value at which PFM/PWM switchover occurs. Inductor Selection The switching frequency and inductor operating point determine the inductor value as follows: − OUT IN OUT ...
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Ignoring the sag due to finite capacitance: ≤ ESR STEP LOAD(MAX) The actual capacitance value required relates to the physical size needed to achieve low ESR, as well as to the ...
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Dynamically Adjustable 6-Bit VID Step-Down Controller significantly higher, consider increasing the size of N Conversely, if the losses at V IN(MAX) higher, consider reducing the size of N not vary over a wide range, maximum efficiency is achieved by selecting ...
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N is the number of high-side MOSFETs used for one regulator, and Q is the gate charge specified GATE in the MOSFET’s data sheet. For example, assume the IRF7821 n-channel MOSFET is used on the high side. According to ...
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Dynamically Adjustable 6-Bit VID Step-Down Controller QSOP LAYOUT EXAMPLE REF V DD ANALOG GROUND CONNECT AGND AND PGND TO THE CONTROLLER AT ONE POINT ONLY AS SHOWN Figure 12. PC Board Layout Example PC Board Layout Guidelines ...
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Layout Procedure 1) Place the power components first, with ground ter- minals adjacent (NL source, C anode). If possible, make all these connections on the top layer with wide, copper-filled areas. 2) Mount the controller IC adjacent to the low-side ...
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Dynamically Adjustable 6-Bit VID Step-Down Controller (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages.) 30 ______________________________________________________________________________________ Package Information PACKAGE OUTLINE, QSOP .150", .025" LEAD PITCH ...
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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 ____________________ 31 © 2005 Maxim Integrated Products ...