AN2504 Datasheet, PDF (11/14 Pages) STMicroelectronics – Using STMicroelectronics Voltage Detectors

AN2504 - Application note
8
Output MOSFET protection
Output MOSFET protection
For applications requiring higher current drive capabilities an external MOSFET might be
used, which protect the output of a voltage detector from overloading and destroying. It is
possible to use either N channel or P channel transistor (see below).
8.1
External N-channel transistor
If the load should be connected to the supply voltage during the regular operation (output,
OUT, is not asserted), an external N-channel transistor will be needed (see Figure 11).
When the supply voltage V_CC drops below the threshold of the voltage detector, the output
signal, OUT, is asserted, the external N-channel MOSFET is switched off and disconnects
the load from the ground.
Figure 11. Circuit with external N-channel transistor
VCC
R
VCC
VCC
STM1061N
OUT
VSS
RLOAD
AI12913
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