M40Z300MH1TR STMICROELECTRONICS [STMicroelectronics], M40Z300MH1TR Datasheet - Page 9

• Manufacturer Part Number: M40Z300MH1TR
• Description: 5V or 3V NVRAM Supervisor for Up to 8 LPSRAMs
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

The M40Z300/W only monitors the battery when a
nominal V
cations which require extensive durations in the
battery back-up mode should be powered-up peri-
odically (at least once every few months) in order
for this technique to be beneficial. Additionally, if a
battery low is indicated, data integrity should be
verified upon power-up via a checksum or other
technique. The BL pin is an open drain output and
an appropriate pull-up resistor to V
chosen to control the rise time.
V
I
switching, can produce voltage fluctuations, re-
sulting in spikes on the V
can be reduced if capacitors are used to store en-
ergy which stabilizes the V
stored in the bypass capacitors will be released as
low going spikes are generated or energy will be
absorbed when overshoots occur. A ceramic by-
pass capacitor value of 0.1µF (as shown in
9.) is recommended in order to provide the needed
filtering.
In addition to transients that are caused by normal
SRAM operation, power cycling can generate neg-
ative voltage spikes on V
below V
spikes can cause data corruption in the SRAM
while in battery backup mode. To protect from
these voltage spikes, STMicroelectronics recom-
mends connecting a schottky diode from V
V
Schottky diode 1N5817 is recommended for
through hole and MBRS120T3 is recommended
for surface mount.
CC
CC
SS
transients, including those produced by output
Noise And Negative Going Transients
(cathode connected to V
SS
CC
by as much as one volt. These negative
is applied to the device. Thus appli-
CC
CC
bus. These transients
CC
that drive it to values
CC
bus. The energy
, anode to V
CC
should be
Figure
CC
SS
to
).
Figure 9. Supply Voltage Protection
V CC
0.1 F
M40Z300, M40Z300W
V CC
V SS
DEVICE
AI00622
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