MC33897DR2 Freescale, MC33897DR2 Datasheet - Page 13

• Manufacturer Part Number: MC33897DR2
• Manufacturer: Freescale

Specifications of MC33897DR2

• Number Of Transceivers: 1
• Power Down Mode: Sleep
• Operating Supply Voltage (max): 40V
• Package Type: SOIC N
• Operating Temperature (max): 125C
• Operating Temperature (min): -40C
• Operating Temperature Classification: Automotive
• Mounting: Surface Mount
• Pin Count: 14
• Lead Free Status / RoHS Status: Not Compliant

device in a Single Wire CAN communications bus.
Communications takes place from a single terminal over a
single wire using a common ground for a current return path.
Two data rates are available, with the high rate used for
factory or assembly line communications and the lower for
control its operation and to process and generate the data for
the bus.
GROUND PINS (33897/A/C/T)
conduction, their number and locations at each of the four
corners serve also to remove heat from the IC. The biggest
benefit of this is obtained by putting a lot of copper on the
PCB in this area and, if ground is an internal layer, by adding
numerous plated-through connections to it with the largest
diameter holes the layout can use.
TXD DATA
TXD terminal. A “1” driven on TXD will result in an undriven
(recessive) state (bus at near zero volts). When the TXD
terminal is low, the output goes to a driven state. The voltage
and waveshaping in the driven state is determined by the
levels on the MODE0 and MODE1 Pins (refer to
Table 6. Mode Control Logic Levels
MODE CONTROL
voltage and the IC sleep mode operation.
mode versus the logic levels on MODE0 and MODE1.
the IC so that in case the Pins are not driven, the device will
enter the sleep mode. This is usually the situation as the
MCU comes out of reset, before the driving signals have
been configured as outputs.
Analog Integrated Circuit Device Data
Freescale Semiconductor
The 33897 Series is intended for use as a physical layer
The 33897 Series is intended to be used with an MCU to
The four ground PINS are not only for electrical
The data driven onto the SWCAN bus is inverted from the
MODE0
The MODE Pins control the transmitter filtering and BUS
The MODE0 and MODE1 Pins have a weak pulldown in
0
0
1
1
Logic Level
MODE1
0
1
0
1
Sleep Mode
High Voltage Wake-Up Mode
High Speed Mode
Normal Mode
Operation
Table 6
FUNCTIONAL DESCRIPTION
FUNCTIONAL PIN DESCRIPTION
Table
shows the
INTRODUCTION
6).
actual system communications where the radiated EMI of the
higher rate could be an issue.
high-speed, and high-voltage wake-up).
RXD Data
on this terminal. This terminal is a logic high when the bus is
in the recessive state (near zero volts) and is logic low when
the bus is in either the normal or high-voltage dominant state.
external resistor to pull it up. When the device is in sleep
mode, the output will be off unless a high-voltage wake-up
level is detected on the bus. If the wake-up level is detected,
the output will be driven by the data on the bus. If the level of
the data returns to normal level, the output will return to off
after a short delay unless a non-sleep mode condition is set
by the MCU.
LOAD Switch
ground is detected. If this happens, the switch is opened and
the resistor normally attached to its terminal will no longer
pass current to or from the bus.
CNTL Output (33897/A/C/T ONLY)
When the output is low, the V
shutdown. This is normally used to shut down the MCU and
all the devices powered by V
This is done to save power. When the part is taken out of the
sleep mode by the higher-than-normal bus voltage, this
terminal is asserted high and the V
output up to the regulated level. This starts the MCU, which
controls the mode of the IC. The MCU must change the mode
signals to non-sleep mode levels in order to keep this
terminal from going low. There is a delay to allow the MCU to
fully wake up and take control after the high-voltage signaling
is removed before the level on this output returns low. After a
delay time, even if the bus is at high voltage, the IC will return
to sleep mode if both MODE Pins are low.
VBATT Input
should use an external diode to protect it from damage owing
to reverse battery if this protection is desired. The voltage
drop of the diode must be taken into consideration when the
operating range of the system is being determined. This
Two Pins control the mode of operation (sleep, low-speed,
The data received on the bus is translated to logic levels
This is an open-drain type of output that requires an
This switch is on in all operating modes unless a loss of
This logic level signal is used to control a V
This power input is not reverse battery protected and
CC
CC
when the IC is in sleep mode.
regulator is expected to
FUNCTIONAL DESCRIPTION
CC
regulator brings its
INTRODUCTION
33897/A/B/C/D/T
CC
regulator.
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