l4948 STMicroelectronics, l4948 Datasheet - Page 6

• Manufacturer Part Number: l4948
• Description: Quad Voltage Regulator With Inhibit And Reset
• Manufacturer: STMicroelectronics

L4948
FUNCTIONAL DESCRIPTION
The L4948 includes a monitoring circuit to warn
the microprocessor if a low voltage or no voltage
condition is occurring. Between 6.5V and 7.5V on
the STCAP pin, the LVW output will go low. This
tells the microprocessor to stop executing code
and save vital information. The reset output will
go low when V
reading. A reset will occur between a minimum of
TIMING DIAGRAM
Graphs of the Output Curves for V
6/9
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drops 0.15V below it’s typical
5.0
5.0
7.8
O1,2,3 and 4
4.5 and a maximum of 5V on V
drops between 4.5 and 5V the RESET output
goes low. It is very important that the RESET out-
put doesn’t go above 0.75V until the V
has gone back above 4.75V (typical). The micro-
processor looks for a rising edge. So, any spike
will tell the microprocessor to start operating.
Once the STCAP line passes 7V (typical), the
LVW output will also return to high state.
04
. When the V
04
output
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