MAX1715EEI Maxim Integrated Products, MAX1715EEI Datasheet
MAX1715EEI
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MAX1715EEI Summary of contents
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... Battery Input Range ♦ 200/300/420/540kHz Nominal Switching Frequency ♦ Over/Undervoltage Protection ♦ 1.7ms Digital Soft-Start ♦ Drives Large Synchronous-Rectifier FETs ♦ Power-Good Indicator PART MAX1715EEI MAX1715EEI+ + Denotes lead-free package. Applications 5V INPUT OUTPUT1 1.8V Features LIMIT Accuracy over Line and Load ...
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Ultra-High Efficiency, Dual Step-Down Controller for Notebook Computers ABSOLUTE MAXIMUM RATINGS V+ to AGND..............................................................-0.3 to +30V AGND ..................................................-0. PGND to AGND ...........................................±0. PGOOD, OUT_ to AGND..........................................-0.3V ...
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Ultra-High Efficiency, Dual Step-Down Controller for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 1, 4A components from Table 1, V noted.) (Note 1) PARAMETER Minimum Off-Time (Note 3) Quiescent Battery Current (V+) Quiescent Supply Current FB1 and FB2 forced ...
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Ultra-High Efficiency, Dual Step-Down Controller for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 1, 4A components from Table 1, V noted.) (Note 1) PARAMETER SKIP, to deactivate OVP circuitry Logic Input Current V CC Float level TON Threshold REF ...
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Ultra-High Efficiency, Dual Step-Down Controller for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 1, 4A components from Table 1, V noted.) (Note 1) PARAMETER Quiescent Battery Current (V+) Quiescent Supply Current FB1 and FB2 forced above the regulation point ...
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Ultra-High Efficiency, Dual Step-Down Controller for Notebook Computers _____________________________Typical Operating Characteristics (continued) (Circuit of Figure 1, components from Table 1, V EFFICIENCY vs. LOAD CURRENT (2.5V, 4A COMPONENTS, SKIP = 100 + ...
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Ultra-High Efficiency, Dual Step-Down Controller for Notebook Computers _____________________________Typical Operating Characteristics (continued) (Circuit of Figure 1, components from Table 1, V FREQUENCY vs. TEMPERATURE (2.5V, 4A COMPONENTS, SKIP = HIGH) 300 250 200 150 100 ...
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Ultra-High Efficiency, Dual Step-Down Controller for Notebook Computers PIN NAME Output Voltage Connection for the OUT1 PWM. Connect directly to the junction of the external inductor and 1 OUT1 output filter capacitors. OUT1 senses the output voltage to determine the ...
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Ultra-High Efficiency, Dual Step-Down Controller for Notebook Computers PIN NAME External Inductor Connection for OUT2. Connect to the switched side of the inductor. LX2 serves as the 16 LX2 lower supply voltage rail for the DH2 high-side gate driver and ...
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Ultra-High Efficiency, Dual Step-Down Controller for Notebook Computers Standard Application Circuit The standard application circuit (Figure 1) generates two low-voltage rails for general-purpose use in note- book computers (I/O supply, fixed CPU core supply, DRAM supply). This DC-DC converter steps ...
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Ultra-High Efficiency, Dual Step-Down Controller for Notebook Computers Table 1. Component Selection for Standard Applications COMPONENT 2. Input Range 7V to 20V Frequency 255kHz Fairchild Q1 High-Side MOSFET Semiconductor 1/2 FDS6982A Fairchild Q2 Low-Side MOSFET Semiconductor 1/2 FDS6982A ...
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Ultra-High Efficiency, Dual Step-Down Controller for Notebook Computers INPUT BST1 DH1 LX1 OUTPUT1 1. DL1 OUT1 FB1 SKIP TON ON1 ON2 P GOOD Figure 2. Functional Diagram current-limit ...
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Ultra-High Efficiency, Dual Step-Down Controller for Notebook Computers 28V TON ON-TIME COMPUTE TRIG 1-SHOT FROM ILIM COMPARATOR FROM ZERO-CROSSING COMPARATOR REF -6% TO PGOOD OR GATE Figure 3. PWM Controller (one side only) Table 3. Operating Mode ...
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Ultra-High Efficiency, Dual Step-Down Controller for Notebook Computers Table 4. Frequency Selection Guidelines NOMINAL TYPICAL FREQUENCY APPLICATION (kHz) Use for absolute best 200 4-cell Li+ notebook efficiency. Considered mainstream 300 4-cell Li+ notebook by current standards. Useful in 3-cell systems ...
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Ultra-High Efficiency, Dual Step-Down Controller for Notebook Computers Δ BATT OUT = Δ ON-TIME TIME Figure 4. Pulse-Skipping/Discontinuous Crossover Point operation, but this is a normal operating condition that results in high light-load efficiency. Trade-offs in ...
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Ultra-High Efficiency, Dual Step-Down Controller for Notebook Computers +5V 5Ω BST DH LX MAX1715 Figure 6. Reducing the Switching-Node Rise Time place the IC close to the low-side MOSFET with short, direct traces, making a Kelvin sense connection to the ...
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Ultra-High Efficiency, Dual Step-Down Controller for Notebook Computers Overvoltage protection can be defeated through the SKIP test mode (Table 3). Output Undervoltage Protection (UVP) The output undervoltage protection function is similar to foldback current limiting, but employs a timer rather ...
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Ultra-High Efficiency, Dual Step-Down Controller for Notebook Computers The inductor ripple current also impacts transient- response performance, especially at low V ferentials. Low inductor values allow the inductor current to slew faster, replenishing charge removed from the output filter capacitors ...
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Ultra-High Efficiency, Dual Step-Down Controller for Notebook Computers The amount of overshoot due to stored inductor energy can be calculated as PEAK ΔV ≈ 2CV OUT where I is the peak inductor current. PEAK Output Capacitor Stability Considerations ...
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Ultra-High Efficiency, Dual Step-Down Controller for Notebook Computers power dissipation (PD) due to resistance occurs at minimum battery voltage: ⎛ ⎞ V OUT = ⎜ ⎟ PD(Q1 resistance) I ⎜ ⎟ LOAD ( ) V ⎝ ⎠ IN MIN Generally, ...
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... The overshoot must be cal- culated to avoid tripping the OVP latch. The efficiency Dual Mode is a trademark of Maxim Integrated Products. ______________________________________________________________________________________ OUT1 V OUT ...
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Ultra-High Efficiency, Dual Step-Down Controller for Notebook Computers 1μF ON/OFF 0.22μ 100k Figure 10. 5V-Powered, 8A CPU Buck Regulator switching frequency and a much smaller inductor value. PC Board Layout Guidelines Careful PC board layout is critical to ...
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Ultra-High Efficiency, Dual Step-Down Controller for Notebook Computers made longer than the discharge path. For example, it’s better to allow some extra distance between the input capacitors and the high-side MOSFET than to allow distance between the inductor and the ...
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Ultra-High Efficiency, Dual Step-Down Controller for Notebook Computers Pin Configuration TOP VIEW OUT1 1 28 FB1 2 27 ILIM1 TON 5 24 MAX1715 SKIP 6 23 PGOOD 7 22 AGND 8 21 REF 9 20 ...
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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. 25 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2005 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products, Inc ...