ST72521R9-Auto STMicroelectronics, ST72521R9-Auto Datasheet - Page 274

• 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

Known limitations
23.2
23.2.1
23.2.2
23.2.3
274/276
All Flash devices
Internal RC oscillator with LVD
The internal RC can only be used if LVD is enabled.
I/O behavior during ICC mode entry sequence
Symptom
In 80-pin devices (Flash), both ports G and H are forced to output push-pull during ICC
mode entry sequence. 80-pin ROM devices are not impacted by this issue.
Details
To enable programming of all Flash sectors, the device must leave USER mode and be
configured in ICC mode. Once in ICC mode, the ICC protocol enables an ST7
microcontroller to communicate with an external controller (such as a PC). ICC mode is
entered by applying 39 pulses on the ICCDATA signal during reset. To enter ICC mode, the
device goes through other modes, some modes are critical because the I/Os PG[7:0] and
PH[7:0] are forced to output push-pull.
Impact on the application
The PG and PH I/O ports are forced to output push-pull during three pulses on ICCDATA. In
certain circumstances, this behavior can lead to a short-circuit between the I/O signals and
V
In addition, switching these I/Os to output mode can cause the application to leave reset
state, disturbing the ICC communication and preventing the user from programming the
Flash.
Readout protection with LVD
The LVD is not supported if readout protection is enabled.
DD
, V
SS
or an output signal of another application component.
Doc ID 17660 Rev 1
ST72521xx-Auto