L99PM72GXP datasheet(25/129 Pages) STMICROELECTRONICS

Part #	L99PM72GXP

Description	Advanced power management system IC with embedded LIN and high speed CAN transceiver supporting CAN Partial Networking

PDF	129 Pages

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Manufacturer	STMICROELECTRONICS [STMicroelectronics]

Direct Link	http://www.st.com

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L99PM72GXP

Detailed description

128

serve the watchdog by alternating the watchdog trigger bit within the safe trigger area (refer

to Figure 32).

A correct watchdog trigger signal immediately starts the next cycle.

After 8 watchdog failures in sequence, the V1 regulator is switched off for 200 ms. If

subsequently, 7 additional watchdog failures occur, the V1 regulator is completely turned off

and the device goes into VBat_standby mode until a wakeup occurs.

In case of a Watchdog failure, the outputs (RELx, OUTx, V2) are switched off and the device

enters Fail_safe mode (i. e. all control registers are set to default values except the 'OUT3

control bit').

The following diagrams illustrate the Watchdog behavior of the L99PM72GXP. The

diagrams are split into 3 parts. First diagram shows the functional behavior of the watchdog

without any error. The second diagram covers the behavior covering all the error conditions,

which can affect the watchdog behavior. Third diagram shows the transition in and out of

FLASH mode. All 3 diagrams can be overlapped to get all the possible state transitions

under all circumstances. For a better readability, they were split in normal operating,

operating with errors and flash mode.

Figure 10. Watchdog in normal operating mode (no errors)

L99PM72GXP Datasheet(PDF) 25 Page - STMicroelectronics