NE56631-20 PHILIPS [NXP Semiconductors], NE56631-20 Datasheet - Page 7

• Manufacturer Part Number: NE56631-20
• Description: Active-LOW system reset
• Manufacturer: PHILIPS [NXP Semiconductors]

Philips Semiconductors
TIMING DIAGRAM
The Timing Diagram in Figure 10 depicts the operation of the device.
Letters A–J on the Time axis indicates specific events.
A: At “A”, V
increases but abruptly decreases when V
(approximately 0.65 V) that activates the internal bias circuitry and
RESET is asserted.
B: At “B”, V
device releases the hold on the V
tracks V
R
events release the reset from the microprocessor, allowing the
microprocessor to function normally.
C-D: At “C”, V
continues to fall until the V
reached at “D”. This causes a reset signal to be generated (V
RESET goes LOW).
2003 Feb 14
PU
Active-LOW system reset
is connected to V
CC
as it rises above V
CC
CC
CC
begins to increase. Also the V
reaches the threshold level of V
begins to fall, causing V
CC
V
V
OUT
). In a microprocessor-based system these
CC
SL
V
V
SH
0
0
SL
undervoltage detection threshold is
A
SH
(assuming the reset pull-up resistor
OUT
reset. The Reset output V
B
CC
OUT
reaches the level
OUT
SH
to follow. V
voltage initially
. At this point the
Figure 10. Timing diagram.
CC
C
OUT
OUT
D
7
E
D-E: Between “D” and “E”, V
E: At “E”, V
releases the hold on the V
as it rises above V
F-G: At “F”, V
causing V
no reset signal will be triggered. Before V
begins to rise, causing V
normal.
H: At event “H”, V
threshold is reached. At this level, a RESET signal is generated and
V
J: At “J”, the V
circuit bias is unable to maintain a V
rise to less than 0.65 V. As V
also decreases to zero.
OUT
TIME
goes LOW.
OUT
F
CC
to follow it. As long as V
CC
CC
rises to the V
SH
is above the upper threshold and begins to fall,
G
CC
voltage has decreased until normal internal
.
falls until the V
OUT
OUT
CC
to follow it. At “G”, V
SH
H
CC
reset. The Reset output tracks V
decreases further, the V
level. Once again, the device
SL01740
starts rising.
OUT
J
SL
CC
undervoltage detection
reset. As a result, V
CC
remains above the V
V
NE56631-XX
S
falls to the V
CC
returns to
Product data
OUT
SH
, it
CC
reset
SH
CC
may
,