M40SZ100 ST Microelectronics, M40SZ100 Datasheet - Page 11

• Manufacturer Part Number: M40SZ100
• Description: 5V or 3V NVRAM SUPERVISOR FOR LPSRAM
• Manufacturer: ST Microelectronics

Power-on Reset Output
All microprocessors have a reset input which forc-
es them to a known state when starting. The
M40SZ100Y/W has a reset output (RST) pin which
is guaranteed to be low by V
page 7). This signal is an open drain configuration.
An appropriate pull-up resistor to V
chosen to control the rise time. This signal will be
valid for all voltage conditions, even when V
equals V
Once V
age V
t
Figure 12. RSTIN Timing Waveform
Note: With pull-up resistor
Table 7. Reset AC Characteristics
Note: 1. Valid for Ambient Operating Temperature: T
REC
2. Pulse width less than 50ns will result in no RESET (for noise immunity).
3. C
to allow the power supply to stabilize.
t
Symbol
PFD
t
R1HRH
RLRH
CC
L
SS
= 5pF (see Figure 8, page 6).
, an internal timer keeps RST low for
RST
RSTIN
exceeds the power failure detect volt-
(2)
(3)
(with valid battery voltage).
(1)
RSTIN Low to RSTIN High
RSTIN High to RST High
PFD
Parameter
(see Table 5,
tRLRH
CC
tR1HRH
should be
A
= –40 to 85°C; V
(1)
CC
CC
Reset Input (RSTIN)
The M40SZ100Y/W provides one independent in-
put which can generate an output reset. The dura-
tion and function of this reset is identical to a reset
generated by a power cycle. Table 7 and Figure 12
illustrate the AC reset characteristics of this func-
tion. Pulses shorter than t
reset condition. RSTIN is internally pulled up to
V
CC
= 2.7 to 3.6V or 4.5 to 5.5V (except where noted).
through a 100k
Min
200
40
M40SZ100Y, M40SZ100W
resistor.
RLRH
Max
200
will not generate a
AI04768
Unit
ms
ns
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