MCZ33989EGR2 Freescale Semiconductor, MCZ33989EGR2 Datasheet - Page 46

• Manufacturer Part Number: MCZ33989EGR2
• Description: IC SYSTEM BASIS CHIP CAN 28-SOIC
• Manufacturer: Freescale Semiconductor

Specifications of MCZ33989EGR2

• Applications: *
• Interface: *
• Voltage - Supply: *
• Package / Case: 28-SOIC (7.5mm Width)
• Mounting Type: Surface Mount
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

CAN Interface Supply
CAN interface also has a supply path from the battery line,
through the pin VSUP. This path is used in CAN sleep mode
to allow wake-up detection.
the CAN interface current is sourced from the V2 pin. During
a CAN low power mode, the current is sourced from the
VSUP pin.
Main Operation Modes Description
operation modes: Normal mode and sleep mode. The modes
are controlled by the SPI command.
slew rates are available for the user.
the remote CAN wake-up capability.
46
33989
TYPICAL APPLICATIONS
SUPPLEMENTAL APPLICATION NOTES
The supply voltage for the CAN driver is the V2 pin. The
During CAN communication (transmission and reception)
The CAN interface of the MC33989 has two main
In normal mode, used for communication, four different
In sleep mode, the user has the option to enable or disable
VSUP
RX
TX
wake-up
Internal
signal
V2
Figure 35. CAN Driver Operation in Normal Mode
SPI control
SPI control
Differential
V2
receiver
Wake-up
pattern
recognition
2.5V
2.5V
Figure 34. 33989 CAN Interface
SPI control
CANH
TX
CANL
RX
Driver
Driver
2.5V
V2
V2
CANH-CANL
Wake- up
CANH-DOM
CANL-DOM
receiver
V2
QL
QH
CAN Driver Operation in Normal Mode
mode, the driver has two states: recessive or dominant. The
driver state is controlled by the TX pin. The bus state is
reported through the RX pin.
CANH and CANL lines are biased to the voltage set at V2
divided by 2, approx. 2.5 V.
CANL and CANH drivers are active. CANL is pulled to gnd,
CANH is pulled high toward 5 V (the voltage at V2).
CANL voltage is compared versus an internal threshold (a
few hundred mV). If “CANH minus CANL” is below the
threshold, the bus is recessive and RX is set high.
dominant and RX is set low. This is illustrated in the figure
below.
When the CAN interface of the MC33989 is in Normal
When TX is high, the driver is set in a recessive state,
When TX is low, the bus is set into dominant state: the
The RX pin reports the bus state: the CANH minus the
If “CANH minus CANL” is above the threshold, the bus is
CANH-REC
CANL-REC
CANH
CANL
Bus termination (60 ohms)
CANH line
CAN L line
Analog Integrated Circuit Device Data
Freescale Semiconductor