ST72521R9-Auto STMicroelectronics, ST72521R9-Auto Datasheet - Page 258

• Manufacturer Part Number: ST72521R9-Auto
• Description: 8-bit MCU for automotive
• Manufacturer: STMicroelectronics

Specifications of ST72521R9-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

Device configuration and ordering information
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Table 163. Option byte 0 bit description (continued)
Table 164. Option byte 1 bit description
OPT4:3
OPT6
OPT5
OPT2
OPT1
OPT0
OPT7
OPT6
Bit
Bit
WDG SW
VD[1:0]
FMP_R
Name
PKG1
RSTC
Name
PKG0
-
-
Package selection bit 1
RESET clock cycle selection
Hardware or software watchdog
Reserved, must be kept at default value.
Voltage detection
Caution: 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. For details on the AVD and LVD
threshold levels refer to
voltage detector
Reserved, must be kept at default value.
Package selection bit 0
Flash memory readout protection
Note: Readout protection is not supported if LVD is enabled.
This option bit, with the PKG0 bit, selects the package (see
Package selection
This option bit selects the number of CPU cycles applied during the
RESET phase and when exiting Halt mode. For resonator oscillators,
it is advised to select 4096 due to the long crystal stabilization time.
0: Reset phase with 4096 CPU cycles
1: Reset phase with 256 CPU cycles
This option bit selects the watchdog type.
0: Hardware (watchdog always enabled)
1: Software (watchdog to be enabled by software)
These option bits enable the voltage detection block (LVD and AVD)
with a selected threshold for the LVD and AVD (EVD + AVD).
00: Selected LVD = Highest threshold (V
01: Selected LVD = Medium threshold (V
10: Selected LVD = Lowest threshold (V
11: LVD and AVD off
This option bit is used to select the package
selection
Readout protection, when selected, provides a protection against
program memory content extraction and against write access to Flash
memory.
Erasing the option bytes when the FMP_R option is selected causes
the whole user memory to be erased first, after which the device can
be reprogrammed. Refer to
page 33
details.
0: Readout protection enabled
1: Readout protection disabled
Doc ID 17660 Rev 1
and the ST7 Flash Programming Reference Manual for more
(OPT7)).
(LVD).
(OPT7)).
Section 20.3.2: Operating conditions with low
Section 4.3.1: Readout protection on
Function
Function
DD
DD
DD
~3V)
~4V)
~3.5V)
(seeTable 165: Package
ST72521xx-Auto
Table 165: