MAX6399 MAXIM [Maxim Integrated Products], MAX6399 Datasheet
MAX6399
Related parts for MAX6399
MAX6399 Summary of contents
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... When the DC-DC monitored output voltage is below the user-adjustable overvoltage threshold, the GATE output of the MAX6399 goes high to enhance the n-channel MOSFET. The MAX6399 offers internal charge-pump circuitry that allows the GATE voltage to be 10V above the input voltage (V ...
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High-Voltage, Overvoltage/Undervoltage, Protection Switch Controller ABSOLUTE MAXIMUM RATINGS IN, GATE, OUT .......................................................-0.3V to +80V SHDN.............................................................-0.3V to (IN + 0.3V) OUT ........................................................................-0.3V to +80V GATE to OUT..........................................................-0.3V to +20V OUT_SET, SET, POK ..............................................-0.3V to +12V Maximum Current (All pins) ................................................50mA Stresses ...
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... POK Leakage Current Note 1: Specifications to -40°C are guaranteed by design and not production tested. Note 2: The MAX6399 powers up with the external FET in off mode (V device is powered up and all input conditions are valid. Note 3: For accurate overtemperature shutdown performance, place the device in close thermal contact with the external MOSFET. ...
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... MAX6399 toc12 V IN 5V/div V GATE 20V/div V OUT 10V/div POK PULLED V POK TO 3.3V 5V/div 100µs/div STARTUP WAVEFORM MAX6399 toc09 POK PULLED 3.3V 10V/div V GATE 10V/div V OUT 10V/div V POK 5V/div 2ms/div MAX6399 toc11 4V V DC_DC 100mV/div V GATE 10V/div V OUT 10V/div ...
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... The device allows system designers to size the external n-channel MOSFET to their load current and board size. GATE The MAX6399 drives the MOSFET’s gate high when the monitored DC-DC output voltage is below the program- OUT mable overvoltage threshold, programmed through SET. An internal charge-pump circuit provides a guar- ...
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... MOSFET if the device reaches overtemperature conditions. Shutdown Control The MAX6399 active-low SHDN input turns off the exter- nal MOSFET, disconnecting the load and reducing power consumption. After power is applied and SHDN is driven above its logic-high voltage, there is a 100µs delay before GATE begins to enhance ...
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... High-Voltage, Overvoltage/Undervoltage, Monitoring for DC-DC Input Undervoltage Conditions The MAX6399 can be used to monitor for an undervolt- age condition at the input of a DC-DC converter or another system voltage by connecting an external resis- tor-divider at OUT_SET (Figure 4). Use the following formula to calculate the undervoltage threshold (V Begin by selecting the total end-to-end resistance ...
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... The MAX6399 thermal-shutdown feature monitors the PC board temperature of the external MOSFET when the devices sit on the same thermal island. Good ther- mal contact between the MAX6399 and the external n-channel MOSFET is essential for the thermal-shut- down feature to effectively operate. Place the n-channel MOSFET as close as possible to OUT ...
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... Select external MOSFETs according to the application current level. The MOSFETs on-resistance (R should be chosen low enough to have minimum voltage drop at full load to limit the MOSFET power dissipation. _______________________________________________________________________________________ Protection Switch Controller Q1 LOAD V BATT MOSFET Selection TRANSISTOR COUNT: 590 ) DS(ON) PROCESS: BiCMOS IN LOAD MAX6399 GATE OUT GND (b) Chip Information 9 ...
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High-Voltage, Overvoltage/Undervoltage, Protection Switch 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.) PIN 1 INDEX AREA -DRAWING NOT TO SCALE- COMMON DIMENSIONS SYMBOL MIN. ...