L99PM72GXP datasheet(18/129 Pages) STMICROELECTRONICS

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Detailed description

L99PM72GXP

18/129

DocID024767 Rev 4

All other device features in Flash Mode are available as in Active Mode.

CAN Transmitter and CAN Receiver are enabled in CAN Flash Mode by default.

A transition from Flash Modes to V1_standby or Vbat_standby is not possible.

The modes can be entered by applying an external voltage at the respective pin:

•

VTxDL > Vflash (CAN Flash Mode)

•

VTxDC > Vflash (LIN Flash Mode)

At exit from Flash Modes (VTxD <Vflash) no NRESET pulse is generated and the watchdog

starts with a long open window.

Note:

Setting both TxDL and TxDC to high voltage levels (> Vflash) is not allowed Communication

at the respective TxD pin is not possible

2.2.3

SW-Debug Mode

To allow software debugging, the watchdog can be deactivated by setting CR34:

WDEN = 0.

Write access to this bit is only possible during CAN Flash Mode in order to prevent

accidental deactivation of the watchdog. After setting the WDEN bit the CAN Flash Mode

can be left (VTxDL <VFlash) and the Watchdog remains deactivated (see Figure 8)

In SW-Debug Mode, the full device functionality is available.

Figure 8. Sequence to enter and exit SW Debug Mode

2.2.4

V1_standby mode

The transition from Active Mode to V1_standby mode is controlled by SPI.

To supply the micro controller in a low power mode, the voltage regulator 1 (V1) remains

active. In order to reduce the current consumption, the regulator goes in low current mode

as soon as the supply current of the microcontroller goes below the ICMP current threshold.

At this transition, the L99PM72GXP also deactivates the internal watchdog.

Relay outputs, LIN and CAN Transmitters are switched off in V1_standby Mode. High side

outputs and the V2 regulator remain in the configuration programmed prior to the standby

command.

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