mc33912 Freescale Semiconductor, Inc, mc33912 Datasheet - Page 27

• Manufacturer Part Number: mc33912
• Description: Lin System Basis Chip With Dc Motor Pre-driver And Current Sense
• Manufacturer: Freescale Semiconductor, Inc

INTERRUPTS
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
Register (ISR).
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.
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.
Request and Stop Mode. Interrupts are not generated while
the RST pin is low.
Normal Request Modes. Some of these can be masked by
writing to the SPI - Interrupt Mask Register (IMR).
Low-voltage Interrupt:
the VSUV threshold (
Analog Integrated Circuit Device Data
Freescale Semiconductor
Interrupts are used to signal a microcontroller that a
While in Stop Mode, interrupts are used to signal wake-up
The interrupts are signaled to the MCU by a low logic level
Interrupts are only asserted while in Normal, Normal
The following is a list of the interrupt sources in Normal and
Signals when the supply line (VS1) voltage drops below
Table 5. Operating Modes Overview
Notes
Current Sense
Analog Mux
55.
56.
57.
58.
59.
Watchdog
Function
VSENSE
HVDD
VDD
HSx
LSx
LIN
Lx
V
Operation can be enabled/controlled by the SPI.
Operation can be controlled by the PWMIN input.
HSx switches can be configured for cyclic sense operation in Stop Mode.
HSx switches can be configured for cyclic sense operation in Sleep Mode.
Windowing operation when enabled by an external resistor.
SUV
).
Reset Mode Normal Request Mode
Full
On
On
-
-
-
-
-
-
-
150ms (typ.) timeout
SPI/PWM
SPI/PWM
Rx-Only
SPI
Inputs
Full
SPI
On
On
(55)
(56)
(56)
Full/Rx-Only Rx-Only/Wake-up
SPI/PWM
SPI/PWM
On
High-voltage Interrupt:
above the VSOV threshold (
Over-temperature Prewarning:
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:
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.
(LINSR) is to indicate an LIN over-current has occurred and
the driver remains enabled.
High Side Over-temperature Shutdown:
Low Side Over-temperature Shutdown:
RESET
time the reset condition lasts.
Normal
Inputs
Mode
Full
SPI
SPI
(59)
On
On
Signals when the supply line (VS1) voltage increases
Signals when the 33912 temperature has reached the pre-
These signal fault conditions within the LIN interface will
The LINOC bit functionality in the LIN Status Register
Signals a shutdown in the high side outputs.
Signals a shutdown in the low side outputs.
To reset a MCU the 33912 drives the RST pin low for the
/Off
Stop Mode
Wake-up
Note
Stop
VDD
-
-
-
-
-
(57)
FUNCTIONAL DEVICE OPERATIONS
V
Sleep Mode
SOV
Wake-up
Wake-up
Note
).
-
-
-
-
-
-
-
(58)
OPERATIONAL MODES
33912
27