sm72240mfx-4.63 National Semiconductor Corporation, sm72240mfx-4.63 Datasheet - Page 8

• Manufacturer Part Number: sm72240mfx-4.63
• Description: Solarmagic 5-pin Microprocessor Reset Circuit
• Manufacturer: National Semiconductor Corporation

NEGATIVE-GOING V
TRANSIENTS
CC
The SM72240 is relatively immune to short negative-going
transients or glitches on V
.
Figure 2
shows the maximum
CC
pulse width a negative-going V
transient can have without
CC
causing a reset pulse. In general, as the magnitude of the
transient increases, going further below the threshold, the
maximum allowable pulse width decreases. Typically, a V
CC
transient that goes 125 mV below the reset threshold and
lasts 40 µs or less will not cause a reset pulse. A 0.1 µF by-
pass capacitor mounted as close as possible to the V
pin
CC
will provide additional transient rejection.
30141414
FIGURE 2. Maximum Transient Duration without Causing
a Reset Pulse vs. Reset Comparator Overdrive
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