MAX1854EEG Maxim Integrated Products, MAX1854EEG Datasheet
MAX1854EEG
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... Converters CORE Ordering Information PART TEMP. RANGE MAX1716EEG -40°C to +85°C MAX1854EEG -40°C to +85°C -40°C to +85°C MAX1855EEG Quick-PWM is a trademark of Maxim Integrated Products. SpeedStep is a trademark of Intel Corp. ________________________________________________________________ Maxim Integrated Products For free samples and the latest literature, visit www.maxim-ic.com or phone 1-800-998-8800. ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning ABSOLUTE MAXIMUM RATINGS V+ to GND ..............................................................-0.3V to +30V GND .....................................................-0. PGND to GND.....................................................................±0.3V SHDN, VGATE to GND .............................................-0.3V to +6V ILIM, FB, ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure +15V values are +25°C.) A PARAMETER SYMBOL BIAS AND REFERENCE Quiescent Supply Current (V ) ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure +15V values are +25°C.) A PARAMETER SYMBOL VGATE Lower Trip Threshold VGATE Upper Trip Threshold ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning ELECTRICAL CHARACTERISTICS (Circuit of Figure +15V PARAMETER SYMBOL PWM CONTROLLER Input Voltage Range DC Output Voltage Accuracy (Notes Input Bias Current ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure +15V PARAMETER SYMBOL Current-Limit Threshold V (Positive, Default) Current-Limit Threshold V (Positive, Adjustable) V Undervoltage Lockout CC ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning (Circuit from Figure 1, components from Table 2, T SKIP MODE (SKIP = GND) A1 4.5V BATT B1 BATT C1 15V BATT D1: V ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning (Circuit from Figure 1, components from Table 2, T EFFICIENCY vs. LOAD CURRENT (1.0V AT 400kHz) 100 ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning (Circuit from Figure 1, components from Table 2, T CURRENT-LIMIT ERROR vs. V ILIM 0.5 1.0 1.5 2.0 2.5 V (V) ILIM NO-LOAD ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning (Circuit from Figure 1, components from Table 2, T LOAD-TRANSIENT RESPONSE (V = 15V, SKIP MODE) BATT 1.60V 1.55V 1.50V 20A 10A 0 40µs/div 1.6V, 50mV/div ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning (Circuit from Figure 1, components from Table 2, T SHORT-CIRCUIT WAVEFORM 20A 10A 20µs/div 1.6V, 1V/div OUT ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning PIN NAME 1 DH High-Side Gate Driver Output. DH swings from LX to BST. Battery Voltage Sense Connection. Connect V+ to input power source used only for PWM 2 ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning PIN NAME Pulse-Skipping or Low-Noise Mode Control Input. Connect to V Connect to GND to enable pulse-skipping operation. Low-noise forced-PWM mode causes inductor SKIP 21 current recirculation at light loads and ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning Table 2. Component Suppliers MANUFACTURER MOSFETs Fairchild Semiconductor International Rectifier Siliconix CAPACITORS Kemet Panasonic Sanyo Taiyo Yuden TDK INDUCTORS Coilcraft Coiltronics Sumida Sumitomo _______________Detailed Description The MAX1716/MAX1854/MAX1855 buck controllers are targeted ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning +5V INPUT BIAS SUPPLY C5 1µF R4 100kΩ POWER-GOOD INDICATOR ON OFF R5 C1 200kΩ R6 0.22µF 100kΩ C2 47pF MAX1716 DAC CODE SHOWN Figure 1. Standard High-Power ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning 28V V+ TON FROM ON-TIME COMPUTE OUT TON TON Q TRIG 1-SHOT SKIP SHDN REF 7R CC 200k gm VPS REF REF +10% -10% VGATE * NO OVERVOLTAGE ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning ∆ BATT OUT = ∆ ON-TIME TIME Figure 3. Pulse-Skipping/Discontinuous Crossover Point switching frequency. The on-time guaranteed in the Electrical Characteristics table is influenced by switch- ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning Table 4. Operating Mode Truth Table SHDN SKIP 0 X High 1 GND Switching 1 V Switching CC 1 Below GND Switching X = Don’t care low-side switch on-time. The resulting ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning +5V 5Ω TYP BST DH LX MAX1716 MAX1854 MAX1855 Figure 5. Reducing the Switching-Node Rise Time V . The logic threshold for switchover to the 120mV CC default value is approximately ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning Table 5. Output Voltage vs. DAC Codes ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning clamped with a Schottky diode to GND to reduce the negative excursion. To ensure correct startup, V+ should be present before the converter attempts to bring the output ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning mal frequency is largely a function of maximum input voltage, due to MOSFET switching losses that are pro- 2 portional to frequency and V+ . The optimum frequency is also a ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning When using low-capacity filter capacitors, such as ceramic or polymer types, capacitor size is usually determined by the capacity needed to prevent V and V from causing problems during load tran- ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning MOSFET Power Dissipation Worst-case conduction losses occur at the duty factor extremes. For the high-side MOSFET (Q1), the worst- case power dissipation due to resistance occurs at the minimum input voltage: ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning DL CS MAX1716 MAX1854 MAX1855 VPS PGND a) SCALED VOLTAGE POSITION SIGNAL Figure 6. Voltage-Positioning Configurations the complete expression for the voltage-positioned out- put depends only upon the value of the ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning VOLTAGE POSITIONING THE OUTPUT MAX1716-Figure 07 1.6V 1.6V A. CONVENTIONAL CONVERTER (50mV/div) B. VOLTAGE POSITIONED OUTPUT (50mV/div) Figure 7. Voltage Positioning the Output ________________Applications Issues Voltage Positioning and Effective Efficiency Powering ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning LOAD OUT 3) Calculate the output current that would exist for each R data point in a nonpositioned LOAD application ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning MAX1716 Q2 DL MAX1854 MAX1855 CS VPS R SENSE PGND R4/R5) OUT FB Figure 9. Adjusting V with a Resistor-Divider OUT adjusted ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning ALL ANALOG GROUNDS CONNECT TO LOCAL PLANE ONLY MAX1717 REF V DD GND CONNECT LOCAL ANALOG GROUND PLANE DIRECTLY TO GND FROM THE SIDE OPPOSITE THE V CAPACITOR ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning +5V INPUT BIAS SUPPLY C5 1µF R4 100kΩ POWER-GOOD INDICATOR ON OFF R5 C1 300kΩ R6 0.22µF 100kΩ C2 47pF MAX1716 DAC CODE SHOWN Figure 11. Low-Current Application ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning +5V INPUT BIAS SUPPLY C5 1µF R4 100kΩ POWER-GOOD INDICATOR ON OFF R5 C1 300kΩ R6 0.22µF 100kΩ C2 47pF MAX1716 DAC CODE SHOWN Figure 12. Low-Voltage Application ...
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High-Speed, Adjustable, Synchronous Step-Down Controllers with Integrated Voltage Positioning +5V INPUT BIAS SUPPLY C5 1µF R4 100kΩ POWER-GOOD INDICATOR ON OFF R5 C1 200kΩ R6 0.22µF 100kΩ C2 47pF MAX1716 DAC CODE SHOWN Figure 13. All-Ceramic-Capacitor Application ...
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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. 33 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2000 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products ...