st7fmc2s7t6 STMicroelectronics, st7fmc2s7t6 Datasheet - Page 31

• Manufacturer Part Number: st7fmc2s7t6
• Description: 8-bit Mcu With Nested Interrupts, Flash, 10-bit Adc, Brushless Motor Control, Five Timers, Spi, Linsci
• Manufacturer: STMicroelectronics

6.3 SYSTEM INTEGRITY MANAGEMENT (SI)
The System Integrity Management block contains
the Low Voltage Detector (LVD), Auxiliary Voltage
Detector (AVD) and Clock Security System (CSS)
functions. It is managed by the SICSR register.
Note: A reset can also be triggered following the
detection of an illegal opcode or prebyte code. Re-
fer to
tails.
6.3.1 Low Voltage Detector (LVD)
The Low Voltage Detector function (LVD) gener-
ates a static reset when the V
below a V
secures the power-up as well as the power-down
keeping the ST7 in reset.
The V
than the V
to avoid a parasitic reset when the MCU starts run-
ning and sinks current on the supply (hysteresis).
The LVD Reset circuitry generates a reset when
V
Figure 17. Low Voltage Detector vs Reset
DD
– V
– V
RESET
is below:
IT-
IT+
IT-
section 11.2.1 on page 243
V
V
reference value for a voltage drop is lower
when V
when V
IT+
IT-
IT+
IT-
reference value for power-on in order
reference value. This means that it
V
DD
DD
DD
is falling
is rising
DD
supply voltage is
for further de-
The LVD function is illustrated in
Provided the minimum V
the oscillator frequency) is above V
can only be in two modes:
In these conditions, secure operation is always en-
sured for the application without the need for ex-
ternal reset hardware.
During a Low Voltage Detector Reset, the RESET
pin is held low, thus permitting the MCU to reset
other devices.
Notes:
The LVD allows the device to be used without any
external RESET circuitry.
The LVD is an optional function which can be se-
lected by option byte.
It is recommended to make sure that the V
ply voltage rises monotonously when the device is
exiting from Reset, to ensure the application func-
tions properly.
V
– under full software control
– in static safe reset
hys
DD
value (guaranteed for
ST7MC1/ST7MC2
Figure
IT-
, the MCU
17.
DD
31/308
sup-
1