Prevent Damage to Electronic Components if a Wrong Adapter Is Plugged In
The MAX4838A/MAX4840A/MAX4842A are overvoltage protection ICs that protect low-voltage systems against voltages of up to +28V. If the input voltage exceeds the overvoltage trip level, the MAX4838A/MAX4840A/MAX4842A turn off the low-cost external n-channel FET(s) to prevent damage to the protected components. An internal charge pump eliminates the need for external capacitors and drives the FET gate for a simple, robust solution. The MAX4838A has a 7.4V overvoltage threshold, and the MAX4840A has a 5.8V overvoltage threshold. The MAX4842A has a 4.7V overvoltage threshold. The MAX4838A/MAX4840A have an undervoltage lockout (UVLO) threshold of 3.25V while the MAX4842A has a UVLO of 2.5V. In addition to the single FET configuration, the devices can be configured with back-to-back external FETs to prevent currents from being back-driven into the adapter. On power-up, the device waits for 50ms before driving GATE high. Active-low FLAG is held low for an additional 50ms after GATE goes high before deasserting. The MAX4838A/MAX4840A/MAX4842A have an open-drain active-low FLAG output. Active-low FLAG output asserts immediately to an overvoltage fault. Additional features include a ±15kV (HBM) ESD-protected input (when bypassed with a 1µF capacitor) and a shutdown pin (active-low EN) to turn off the device. All devices are offered in a small 6-pin SC70 package and 6-pin 1.5mm x 1.0mm µDFN packages and are specified over the extended temperature range of -40°C to +85°C.
title | Download file |
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MAX4838A-MAX4842A Data Sheet | MAX4838A-MAX4842A.pdf |
Part Number | Channels | VIN (V) | VIN (V) | Over Voltage Trip Level (V) | Under Voltage Lockout (V) | VGATE (V) | Over Volt. Flag | tGATE (On) (ms) | tGATE (Off) (µs) | Package/Pins | Budgetary Price |
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min | max | See Notes | |||||||||
MAX4838A | 1 | 1.2 | 28 | 7.4 | 3.25 | 10 | Open-Drain | 10 | 6 | µDFN/6 SC-70/6 | - |
MAX4840A | 5.8 | 3.25 | µDFN/6 SC-70/6 | $1.05 @1k | |||||||
MAX4842A | 4.7 | 2.5 | µDFN/6 SC-70/6 | - | |||||||
Part Number | Status | Recommended Replacement | Package | Temp | RoHS |
---|---|---|---|---|---|
MAX4842AELT+T | No Longer Available | µDFN,;6 pin;1.6 mm² | -40°C to +85°C | Lead Free | |
MAX4842AEXT+T | Active | SC-70,;6 pin;5.3 mm² | -40°C to +85°C | Lead Free |