M40SZ100WMH6E STMICROELECTRONICS [STMicroelectronics], M40SZ100WMH6E Datasheet - Page 12

• Manufacturer Part Number: M40SZ100WMH6E
• Description: 5 V or 3 V NVRAM supervisor for LPSRAM
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

Operation
2.2
2.3
2.4
12/24
Power-on reset output
All microprocessors have a reset input which forces them to a known state when starting.
The M40SZ100Y/W has a reset output (RST) pin which is guaranteed to be low by V
(see
resistor to V
voltage conditions, even when V
Once V
for t
Reset input (RSTIN)
The M40SZ100Y/W provides one independent input which can generate an output reset.
The duration and function of this reset is identical to a reset generated by a power cycle.
Table 3
than t
100 kΩ resistor.
Figure 8.
1. With pull-up resistor
Table 3.
1. Valid for ambient operating temperature: T
2. Pulse width less than 50 ns will result in no RESET (for noise immunity).
3. C
Battery low pin
The M40SZ100Y/W automatically performs battery voltage monitoring upon power-up, and
at factory-programmed time intervals of at least 24 hours. The Battery Low (BL) pin will be
asserted if the battery voltage is found to be less than approximately 2.5 V. The BL pin will
remain asserted until completion of battery replacement and subsequent battery low
monitoring tests, either during the next power-up sequence or the next scheduled 24-hour
interval.
where noted).
RST
REC
RSTIN
t
L
Symbol
Table 7 on page
t
R1HRH
RLRH
RLRH
= 5 pF (see
(1)
CC
and
to allow the power supply to stabilize.
(2)
(3)
exceeds the power failure detect voltage V
will not generate a reset condition. RSTIN is internally pulled up to V
CC
Figure 8
RSTIN timing waveform
Reset AC characteristics
should be chosen to control the rise time. This signal will be valid for all
Figure 10 on page
RSTIN low to RSTIN high
RSTIN high to RST high
illustrate the AC reset characteristics of this function. Pulses shorter
17). This signal is an open drain configuration. An appropriate pull-up
Parameter
tRLRH
16).
Doc ID 7528 Rev 3
CC
tR1HRH
equals V
A
(1)
= –40 to 85 °C; V
SS
(with valid battery voltage).
CC
PFD
= 2.7 to 3.6 V or 4.5 to 5.5 V (except
Min
200
40
, an internal timer keeps RST low
M40SZ100Y, M40SZ100W
Max
200
CC
through a
Unit
ms
ns
PFD
AI04768