MAX1761EEE Maxim Integrated Products, MAX1761EEE Datasheet
MAX1761EEE
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MAX1761EEE Summary of contents
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... Complementary Synchronous Buck o No Current-Sense Resistor o 4.65V at 25mA Linear Regulator Output o 4µA V+ Shutdown Supply Current o 5µA VL Shutdown Supply Current o 950µA Quiescent Supply Current o Tiny 16-Pin QSOP Package PART MAX1761EEE TOP VIEW FB1 OUT1 REF ON2 ON1 OUT2 FB2 ...
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Small, Dual, High-Efficiency Buck Controller for Notebooks ABSOLUTE MAXIMUM RATINGS V+ to GND ..............................................................-0.3V to +22V VL to GND ................................................................-0. .............................................................................+0.3V OUT_, ON2 to GND ..................................................-0.3V to +6V ON1, DH_ to GND ........................................-0.3V to (V+ ...
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ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 15V 4.7µ otherwise noted.) (Note 1) PARAMETER SYMBOL FAULT PROTECTION Output Undervoltage Threshold V FB,UVFB (Foldback) Output Undervoltage Blanking V FB,UVLO(t) Time Current-Limit Threshold Thermal Shutdown Threshold ...
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Small, Dual, High-Efficiency Buck Controller for Notebooks ELECTRICAL CHARACTERISTICS (Circuit of Figure 15V 4.7µ unless otherwise noted.) (Note 1) PARAMETER SYMBOL PWM CONTROLLERS V+ Input Voltage Range VL DC Output Voltage Accuracy V ...
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ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 15V 4.7µ unless otherwise noted.) (Note 1) PARAMETER SYMBOL GATE DRIVERS DH_ Gate Driver On-Resistance (Pullup) DH_ Gate Driver On-Resistance (Pulldown) DL_ Gate Driver On-Resistance (Pullup) DL_ ...
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Small, Dual, High-Efficiency Buck Controller for Notebooks (T = +25°C, unless otherwise noted.) A EFFICIENCY vs. LOAD CURRENT (V = 2.5V, SKIP MODE) OUT 100 + + +12V ...
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A SUPPLY CURRENT vs. INPUT VOLTAGE (SKIP MODE) 0.7 0.6 0.5 0.4 0.3 0.2 ON1 = VL, ON2 = VL 0.1 NO LOAD 0 4.5 6.5 8.5 10.5 12.5 14.5 16.5 18.5 20.5 INPUT ...
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Small, Dual, High-Efficiency Buck Controller for Notebooks PIN NAME Feed b ack Inp ut for the 2. onnect FB1 for a fi xed 2.5V outp ut. C onnect a r esi sti ve ...
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V OUT1 2.5V 220µF Figure 1. Typical Application Circuit Typical Application Circuit The typical application circuit in Figure 1 generates two low-voltage rails for general-purpose use in notebook and subnotebook computers (I/O supply, fixed CPU core supply, DRAM supply). This ...
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Small, Dual, High-Efficiency Buck Controller for Notebooks Table 1. Component Selection for Standard Applications COMPONENT 2.5V AT 2.0A Input Range 5V to 18V Frequency 350kHz Complementary P- and N-Channel Fairchild FDS8958A MOSFETs 7µH Inductor Sumida CDRH104- 7R0NC 10µF, 25V Input ...
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OUT1 C IN1 Q1 L1 OUT1 C OUT1 D1 Q2 ON1 Figure 2. Functional Diagram On-Time One-Shot The heart of the PWM core is the one-shot that sets the high-side switch on-time for both controllers. This fast, ...
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Small, Dual, High-Efficiency Buck Controller for Notebooks V IN ON-TIME OUT COMPUTE TON TON TRIG Q 1-SHOT REF MAX1761 SHDN ON/OFF TIMER SHDN CONTROL Figure 3. PWM Controller (One Side Only) The maximum on-time and minimum off-time, t one-shots restrict ...
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Automatic Pulse-Skipping Switchover In normal operation, the MAX1761’s PWM control algo- rithm automatically skips pulses at light loads. Comparators at each CS_ input in the MAX1761 trun- cate the low-side switch’s on-time at the point where the inductor current drops ...
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Small, Dual, High-Efficiency Buck Controller for Notebooks 0 TIME Figure 5. “Valley” Current-Limit Threshold Point V+ DH MAX1761 DL CS OUT FB Figure 6. Using a Low-Side Current-Sense Resistor MOSFET Gate Drivers The DH and DL outputs are optimized for ...
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Table 4. Operating Mode Control Summary MODE ON1 Shutdown ON1 < 0.5V ON1 Enabled 2.0V < ON1 < V+ Forced PWM 2.0V < ON1 < V+ Normal Operation 2.0V < ON1 < V+ Thermal Fault Protection The MAX1761 features a ...
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Small, Dual, High-Efficiency Buck Controller for Notebooks × × × 350 kHz Find a low-loss inductor having ...
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ESR × × 2π R ESR For a typical 350kHz application, the ESR zero frequen- cy must be well below 100kHz, preferably below 50kHz. Tantalum and OS-CON capacitors have typical ESR zero frequencies of 15kHz. Sanyo ...
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Small, Dual, High-Efficiency Buck Controller for Notebooks • A dual N-channel and a dual P-channel MOSFET (Figure 8) • Two single N-channels and a dual P-channel (Figure 9) • Two single N-channels and two single P-channels (Figure 10) There are ...
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DH1 DH2 Figure 8. Dual N- and P-Channel MOSFET Design LX1 P-CHANNEL DH1 P-CHANNEL DH2 LX2 Figure 9. Two Single N-Channel MOSFETs ...
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Small, Dual, High-Efficiency Buck Controller for Notebooks tolerances and internal propagation delays introduce an error to the t K-factor. Also, keep in mind that ON transient response performance of buck regulators operated close to dropout is poor, and bulk output ...
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OUT1 TO ERROR TO ERROR FIXED AMP1 AMP2 2.5V FB1 0.1V MAX1761 Figure 11. Feedback MUX V+ DH 1/2 CS MAX1761 DL GND OUT FB Figure 12. Setting V with a Resistive Voltage-Divider OUT • When trade-offs in trace lengths ...
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Small, Dual, High-Efficiency Buck Controller for Notebooks USE AGND PLANE TO: USE PGND PLANE TO: - BYPASS V AND REF - BYPASS TERMINATE EXTERNAL FB - CONNECT PGND TO THE TOPSIDE DIVIDER (IF USED) STAR GROUND - ...
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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 ____________________ 23 © 2000 Maxim Integrated Products ...