33912 Datasheet, PDF(27/47 Page) Freescale Semiconductor, Inc – LIN System Basis Chip with DC Motor Pre-driver and Current

English

English German Russian Spanish Italian Polish Chinese Japanese Korean French Portuguese	Language :

33912 Datasheet, PDF (27/47 Pages) Freescale Semiconductor, Inc – LIN System Basis Chip with DC Motor Pre-driver and Current

◁

FUNCTIONAL DEVICE OPERATIONS

OPERATIONAL MODES

Table 5. Operating Modes Overview

Function

Reset Mode Normal Request Mode

Normal

Mode

Stop Mode Sleep Mode

VDD

Full

HVDD

LSx

HSx

Full

SPI(55)

SPI/PWM(56)

Full

SPI

SPI/PWM

Stop

Note(57)

Note(58)

Analog Mux

SPI

Inputs

Wake-up

Current Sense

LIN

Watchdog

Rx-Only

Full/Rx-Only Rx-Only/Wake-up Wake-up

150ms (typ.) timeout On(59)/Off

VSENSE

VDD

Notes

55. Operation can be enabled/controlled by the SPI.

56. Operation can be controlled by the PWMIN input.

57. HSx switches can be configured for cyclic sense operation in Stop Mode.

58. HSx switches can be configured for cyclic sense operation in Sleep Mode.

59. Windowing operation when enabled by an external resistor.

INTERRUPTS

Interrupts are used to signal a microcontroller that a

peripheral needs to be serviced. The interrupts which can be

generated, change according to the operating mode. While in

Normal and Normal Request Modes, the 33912 signals

through interrupts special conditions which may require a

MCU software action. Interrupts are not generated until all

pending wake-up sources are read in the Interrupt Source

While in Stop Mode, interrupts are used to signal wake-up

events. Sleep Mode does not use interrupts. Wake-up is

performed by powering-up the MCU. In Normal and Normal

Request Mode the wake-up source can be read by SPI.

The interrupts are signaled to the MCU by a low logic level

of the IRQ pin, which will remain low until the interrupt is

acknowledged by a SPI read. The IRQ pin will then be driven

high.

Interrupts are only asserted while in Normal, Normal

Request and Stop Mode. Interrupts are not generated while

the RST pin is low.

The following is a list of the interrupt sources in Normal and

Normal Request Modes. Some of these can be masked by

writing to the SPI - Interrupt Mask Register (IMR).

Low-voltage Interrupt:

Signals when the supply line (VS1) voltage drops below

the VSUV threshold (VSUV).

High-voltage Interrupt:

Signals when the supply line (VS1) voltage increases

above the VSOV threshold (VSOV).

Over-temperature Prewarning:

Signals when the 33912 temperature has reached the pre-

shutdown warning threshold. It is used to warn the MCU that

an over-temperature shutdown in the main 5V regulator is

imminent.

LIN Over-current Shutdown / Over-temperature

Shutdown / TXD Stuck At Dominant / RXD Short-circuit:

These signal fault conditions within the LIN interface will

cause the LIN driver to be disabled, except for the LIN over-

current condition. In order to restart operation, the fault must

be removed and must be acknowledged by reading the SPI.

The LINOC bit functionality in the LIN Status Register

(LINSR) is to indicate an LIN over-current has occurred and

the driver remains enabled.

High Side Over-temperature Shutdown:

Signals a shutdown in the high side outputs.

Low Side Over-temperature Shutdown:

Signals a shutdown in the low side outputs.

RESET

To reset a MCU the 33912 drives the RST pin low for the

time the reset condition lasts.

Analog Integrated Circuit Device Data

Freescale Semiconductor

33912

▷