MAX3058 Datasheet, PDF (9/12 Pages) Maxim Integrated Products – 5V, 1Mbps, Low Supply Current CAN Transceivers

5V, 1Mbps, Low Supply Current
CAN Transceivers
Detailed Description
The MAX3058/MAX3059 interface between the protocol
controller and the physical wires of the bus lines in a
CAN. They are primarily intended for printer and tele-
com backplane applications requiring data rates up to
1Mbps. These devices provide differential transmit
capability to the bus and differential receive capability
to the CAN controller.
The MAX3058 output common-mode range is from -7V
to +12V. The MAX3059 output common-mode range is
from 0V to V_CC. The MAX3059 contains an internal
switch termination resistor that makes it ideal for JetLink
applications.
The MAX3058 features four different modes of opera-
tion: high-speed, slope control, standby, and shut-
down. The MAX3059 features three different modes of
operation: high speed, slope control, and shutdown.
High-speed mode allows data rates up to 1Mbps. In
slope-control mode, the slew rate may be optimized for
data rates up to 500kbps, so the effects of EMI are
reduced, and unshielded twisted or parallel cable can
be used. In standby mode, the transmitters are shut off
and the receivers are put into low-current mode. In
shutdown mode, the transmitter and receiver are
switched off.
The transceivers operate from a single +5V supply and
draw 40mA of supply current in dominant state and 2mA
in recessive state. In standby mode, supply current is
reduced to 15µA. In shutdown mode, supply current is
1µA for the MAX3058 and 5µA for the MAX3059.
CANH and CANL are output short-circuit current limited
and are protected against excessive power dissipation
by thermal-shutdown circuitry that places the driver
outputs into a high-impedance state.
Transmitter
The transmitter converts a single-ended input (TXD)
from the CAN controller to differential outputs for the
bus lines (CANH, CANL). The truth table for the trans-
mitter and receiver is given in Tables 1 and 2.
Table 1. Transmitter and Receiver Truth Table for MAX3058 When Not Connected to
the Bus
TXD
Low
High or float
X
X
RS
V_RS < 0.75 x V_CC
V_RS < 0.75 x V_CC
V_RS > 0.75 x V_CC
X
SHDN
Low
Low
Low
High
CANH
High
5kΩ to 25kΩ to
V_CC/2
5kΩ to 25kΩ to
GND
Floating
CANL
Low
5kΩ to 25kΩ
to V_CC/2
5kΩ to 25kΩ
to GND
Floating
BUS STATE
Dominant
Recessive
Recessive
Floating
RXD
Low
High
High
High
Table 2. Transmitter and Receiver Truth Table for MAX3059 When Not Connected to
the Bus
TXD
Low
Low
High or float
High or float
X
X
RS
V_RS < 0.75 x V_CC
V_RS < 0.75 x V_CC
V_RS < 0.75 x V_CC
V_RS < 0.75 x V_CC
V_RS > 0.75 x V_CC
V_RS > 0.75 x V_CC
TERM
Low
High
Low
High
Low
High
CANH
CANL
High
Low
High
Low
120Ω terminating resistor across
5kΩ to 25kΩ to
V_CC/2
5kΩ to 25kΩ to
V_CC/2
5kΩ to 25kΩ to
V_CC/2
5kΩ to 25kΩ to
V_CC/2
120Ω terminating resistor across
Floating
Floating
Floating
Floating
120Ω terminating resistor across
BUS STATE
Dominant
Dominant
Recessive
Recessive
Floating
Floating
RXD
Low
Low
High
High
High
High
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