ST72321AR6-Auto STMicroelectronics, ST72321AR6-Auto Datasheet - Page 43

• Manufacturer Part Number: ST72321AR6-Auto
• Description: 8-bit MCU for automotive with 32 Kbyte Flash, 10-bit ADC, timers, SPI, SCI and I2C interfaces
• Manufacturer: STMicroelectronics

Specifications of ST72321AR6-Auto

• Hdflash Endurance: 100 cycles, data retention 20 years
• Clock Sources: crystal/ceramic resonator oscillators, internal RC oscillator and bypass for external clock
• 4 Power Saving Modes: Halt, Active Halt, Wait and Slow

ST72321xx-Auto
6.6
6.6.1
Note:
System integrity management (SI)
The System Integrity Management block contains the Low Voltage Detector (LVD) and
Auxiliary Voltage Detector (AVD) functions. It is managed by the SICSR register.
Low voltage detector (LVD)
The low voltage detector function (LVD) generates a static reset when the V
voltage is below a V
the power-down keeping the ST7 in reset.
The V
on in order to avoid a parasitic reset when the MCU starts running and sinks current on the
supply (hysteresis).
The LVD reset circuitry generates a reset when V
The LVD function is illustrated in
The voltage threshold can be configured by option byte to be low, medium or high.
Provided the minimum V
MCU can only be in two modes:
In these conditions, secure operation is always ensured for the application without the need
for external reset hardware.
During a low voltage detector reset, the RESET pin is held low, thus permitting the MCU to
reset other devices.
The LVD allows the device to be used without any external RESET circuitry.
If the medium or low thresholds are selected, the detection may occur outside the specified
operating voltage range. Below 3.8V, device operation is not guaranteed.
The LVD is an optional function which can be selected by option byte.
It is recommended to make sure that the V
device is exiting from Reset, to ensure the application functions properly.
–
–
–
–
IT-
reference value for a voltage drop is lower than the V
V
V
under full software control
in static safe reset
IT+
IT-
when V
when V
IT-
DD
DD
reference value. This means that it secures the power-up as well as
is falling
DD
is rising
value (guaranteed for the oscillator frequency) is above V
Doc ID 13829 Rev 1
Figure
14.
DD
supply voltage rises monotonously when the
DD
Supply, reset and clock management
is below:
IT+
reference value for power-
DD
supply
IT-
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, the