In normal operating mode, internal GATE1 output cir-

gate-source junction is not overstressed during high-

battery-voltage application or transients (many MOSFET

power dissipation is very low:

During reverse-battery applications, GATE1 is limited to

GND and the P1 gate-source junction is reverse

biased. P1 is turned off and neither the MAX16013/

MAX16014 nor the load circuitry is exposed to the

reverse-battery voltage. Care should be taken to place

P1 (and its internal drain-to-source diode) in the correct

orientation for proper reverse battery operation.

P2 protects the load from input overvoltage conditions.

During normal operating modes (the monitored voltage

is below the adjusted overvoltage threshold), internal

GATE2 output circuitry enhances P2 to a 10V gate-to-

mode but the gate-to-source junction is not over-

stressed during high-battery-voltage applications

tion, the P2 power dissipation is very low:

During overvoltage conditions, P2 is either turned com-

pletely off (overvoltage-switch mode) or cycled off-on-

off (voltage-limiter mode). Care should be taken to

place P2 (and its internal drain-to-source diode) in the

correct orientation for proper overvoltage protection

operation. During voltage-limiter mode, the drain of P2

is limited to the adjusted overvoltage threshold, while

voltage events, P2 temperature can increase rapidly

due to the high power dissipation. The power dissipat-

ed by P2 is:

load limit voltage. For prolonged overvoltage events with

high P2 power dissipation, proper heatsinking is required.

Adding External Pullup Resistors

It may be necessary to add an external resistor from

capability when the GATE1 input goes high. The

GATE_ output can only source up to 1µA current. If the

source current is less than 1µA, no external resistor

may be necessary. However, to improve the pullup

capability of the GATE_ output when it goes high, con-

The application shows a 2M

Ω resistor, which is large

enough not to impact the sinking capability of the

GATE_ (during normal operation) while providing

enough pullup during an overvoltage event. With an

sinking current of 75µA, the smallest resistor should be

11V/75µA, or about 147k

Ω. However, since the GATE_

is typically low most of the time, a higher value should

be used to reduce overall power consumption.

Ultra-Small, Overvoltage Protection/

Detection Circuits

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