33742_08 Datasheet, PDF (25/70 Pages) Freescale Semiconductor, Inc – System Basis Chip with Enhanced High Speed CAN Transceiver

FUNCTIONAL DESCRIPTION
FUNCTIONAL INTERNAL BLOCK DESCRIPTION
FUNCTIONAL INTERNAL BLOCK DESCRIPTION
MC33742 - Functional Block Diagram
Integrated Supply
VSUP Control & Monitor
Analog Circuitry
Oscillator
Mode Control
Programmable Wake-up
MCU Interface
SPI Interface
CAN Interface / Control
Reset & INT
Watchdog Timer
Outputs
5.0V Linear
Regulator (LDO)
5.0V Regulator
Base PNP Drive
High-side
Switch
CAN Physical Layer
Interface
Integrated Supply
Analog Circuitry
MCU Interface
Outputs
OUTPUTS
5.0V LINEAR REGULATOR (LDO)
This low dropout linear regulator (V1) outputs a regulated
5.0V at 200mA. The associated monitoring circuit provides
detection of under-voltage, over-current, and short-circuit
conditions, as well as over-temperature and a reset function.
5.0V REGULATOR BASE PNP DRIVE
The V2 linear regulator control circuitry provides drive for
an external series pass transistor (PNP type). The 5.0V
output tracks the V1 regulator
HIGH SIDE SWITCH
The high switch provides a 2.0 Ohm (typ.) RDS_ON
MOSFET driver connected to the VSUP pin. The output is
protected against short-circuit conditions and provides over-
temperature shutdown.
CAN PHYSICAL LAYER INTERFACE
This circuitry provides communication between the TXD &
RXD pins, from/to the MCU, and the CANL & CANH pins of
the CAN physical interface. The various modes of the CAN
interface are controlled through the SPI control registers.
INTEGRATED SUPPLY
VSUP CONTROL & MONITOR
This circuitry protects the IC from transient conditions such
as vehicle jump-start (27V) and load dump (40V). If the V_SUP
voltage falls below 3.0V (or a 6.0V warning interrupt), an
under-voltage detection is reported.
ANALOG CIRCUITRY
OSCILLATOR
This circuit is used to generate the internal timings for
reset, watchdog, cyclic wake-up, filtering time, etc.
MODE CONTROL
The 4 operating modes of the IC are controlled through the
SPI control registers. There are also several special modes
possible.
PROGRAMMABLE WAKE-UP
The 4 inputs are used in conjunction with various SPI
control register bits to determine the wake-up conditions and
the reaction of the IC. They can be connected to contact
switches or other ICs.
Analog Integrated Circuit Device Data
Freescale Semiconductor
33742
25