ST72521R9-Auto STMicroelectronics, ST72521R9-Auto Datasheet - Page 66

• 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

Power saving modes
8.3
66/276
Figure 23. Slow mode clock transitions
Wait mode
Wait mode places the MCU in a low power consumption mode by stopping the CPU.
This power saving mode is selected by calling the ‘WFI’ instruction.
All peripherals remain active. During Wait mode, the I[1:0] bits of the CC register are forced
to ‘10’, to enable all interrupts. All other registers and memory remain unchanged. The MCU
remains in Wait mode until an interrupt or RESET occurs, whereupon the Program Counter
branches to the starting address of the interrupt or Reset service routine.
The MCU will remain in Wait mode until a Reset or an Interrupt occurs, causing it to wake
up.
Refer to the following
CP1:0
SMS
f
CPU
f
Figure
OSC2
24.
Doc ID 17660 Rev 1
00
f
FREQUENCY
OSC2/2
NEW SLOW
REQUEST
01
NORMAL RUN MODE
f
OSC2/4
REQUEST
ST72521xx-Auto
f
OSC2