To prevent this situation a delay capacitor is required at pin

8 The selection of a minimum capacitor value to ensure

proper start-up depends primarily on the load characteristics

and how much time is required for the MOSFET to raise the

load voltage to the point where the Sense input is more

mentation is required if a specific minimum delay time char-

acteristic is desired Therefore

In the absence of a specific delay time requirement a value

OVER VOLTAGE PROTECTION

LM9061 will turn off the MOSFET to protect the load from

operating range the device will return to normal operation

without requiring toggling the ONOFF input This feature

will allow MOSFET operation to continue in applications that

are subject to periodic voltage transients such as automo-

tive applications

For circuits where the load is sensitive to high voltages the

circuit shown in

Figure 5 can be used The addition of a

zener on the Sense input (pin 1) will provide a maximum

voltage reference for the Protection Comparator The Sense

resistor is required in this application to limit the zener cur-

rent When the device is ON and the load supply attempts

comparator will trip and the Delay Timer will start If the high

supply voltage condition lasts long enough for the Delay

Timer to time out the MOSFET will be latched off The ON

OFF input will need to be toggled to restart the MOSFET

TLH12317 – 13

FIGURE 5 Adding Over-Voltage Protection

REVERSE BATTERY

The LM9061 is not protected against reverse polarity supply

be limited to 20 mA The addition of a diode in series with

subtract significantly from the charge pump gate overdrive

output voltage

LOW BATTERY

As an additional protection feature the LM9061 incorporates

package drops below 7V where it may not be assured that

the MOSFET is actually ON when it should be circuitry will

automatically turn OFF the power MOSFET

Figure 6 shows the LM9061 used as an electronic circuit

breaker This circuit provides low voltage shutdown over-

voltage latch OFF and overcurrent latch OFF In the event

of a latch OFF shutdown the circuit can be reset by shutting

the main supply off then back on An optional reset switch

on the ONOFF pin will allow a ‘‘push-button reset’’ of the

circuit after latching OFF

TLH12317 – 14

FIGURE 6 Electronic Circuit Breaker

OFF input pin with the internal 30k resistor can be used to

increase the startup voltage The circuit operation then be-

ONOFF pin voltage being above the ON threshold rather

DRIVING MOSFET ARRAYS

The LM9061 is an ideal driver for any application that re-

quires multiple parallel MOSFETs to provide the necessary

load current Only a few ‘‘common sense’’ precautions need

to be observed All MOSFETs in the array must have identi-

cal electrical and thermal characteristics

This can be

solved by using the same part number from the same

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