Detailed Description
The MAX13050/MAX13052/MAX13053/MAX13054 ±80V
fault-protected CAN transceivers are ideal for industrial
network applications where overvoltage protection is
required. These devices provide a link between the CAN
protocol controller and the physical wires of the bus lines
in a control area network (CAN). These devices can be
used for DeviceNet applications, requiring data rates up
to 1Mbps.
The devices’ dominant timeout prevents the bus from
being blocked by a hungup microcontroller. If the TXD
input is held low for greater than 1ms, the transmitter
becomes disabled, driving the bus line to a recessive
state. The MAX13054 +3.3V logic input allows the device
to communicate with +3.3V logic, while operating from
a +5V supply. The MAX13050 and MAX13052 provide
a split DC-stabilized voltage. The MAX13053 has a
reference output that can be used to bias the input of a
CAN controller’s differential comparator.
All devices can operate up to 1Mbps (high-speed mode).
The MAX13052 slope-control feature allows the user to
program the slew rate of the transmitter for data rates
of up to 500kbps. This reduces the effects of EMI, thus
allowing the use of unshielded-twisted or parallel cable.
The MAX13050/MAX13052 and MAX13054 standby
mode shuts off the transmitter and switches the receiver
to a low-current/low-speed state.
The device input common-mode range is greater than
±12V, exceeding the ISO11898 specification of -2V to +7V,
and feature ±8kV Contact Discharge protection, making
these devices ideal for harsh industrial environments.
±80V Fault Protected
The devices feature ±80V fault protection. This extended
voltage range of CANH, CANL, and SPLIT allows use
in high-voltage systems and communication with high-
voltage buses.
Operating Modes
High-Speed Mode
The devices can achieve transmission rates of up to
1Mbps when operating in high-speed mode. Drive STBY
low to operate the MAX13050 and MAX13054 in high-
speed operation. Connect RS to ground to operate the
MAX13052 in high-speed mode.
Slope-Control Mode (MAX13052)
Connect a resistor from RS to ground to select slope-
control mode (Table 1). In slope-control mode, CANH
and CANL slew rates are controlled by the resistor (16kΩ
≤ RRS ≤ 200kΩ) connected between RS and GND.
Controlling the rise and fall slopes reduces high-frequency
EMI and allows the use of an unshielded-twisted pair or
a parallel pair of wires as bus lines. The slew rate can be
approximated using the formula below:
RS
250
SR(V / µs) R
=
where, SR is the desired slew rate and RRS is in kΩ.
Standby Mode (MAX13050/MAX13052/MAX13054)
In standby mode (RS or STBY = high), the transmitter
is switched off and the receiver is switched to a low-
current/low-speed state. The supply current is reduced
during standby mode. The bus line is monitored by a low-
differential comparator to detect and recognize a wake-
up event on the bus line. Once the comparator detects
a dominant bus level greater than tWAKE, RXD pulls low.
Drive STBY high for standby mode operation for the
MAX13050 and MAX13054. Apply a logic-high to RS to
enter a low-current standby mode for the MAX13052.
Silent Mode S (MAX13053)
Drive S high to place the MAX13053 in silent mode.
When operating in silent mode, the transmitter is disabled
regardless of the voltage level at TXD. RXD however, still
monitors activity on the bus line.
Common-Mode Stabilization (SPLIT)
SPLIT provides a DC common-mode stabilization
voltage of 0.5 x VCC when operating in normal mode.
SPLIT stabilizes the recessive voltage to 0.5 x VCC for
conditions when the recessive bus voltage is lowered,
caused by an unsupplied transceiver in the network with
a significant leakage current from the bus lines to ground.
Use SPLIT to stabilize the recessive common-mode
voltage by connecting SPLIT to the center tap of the split
termination, see the Typical Operating Circuits. In standby
mode or when VCC = 0, SPLIT becomes high impedance.
Table 1. Mode Selection Truth Table
MAX13052
CONDITION FORCED
AT RS MODE RESULTING
CURRENT AT RS
VRS or ≤ 0.3 x VCC High-Speed |IRS| ≤ 500µA
0.4 x VCC ≤ VRS ≤ 0.6
x VCC
Slope Control 10µA ≤ |IRS| ≤ 200µA
VRS ≥ 0.75 x VCC Standby |IRS| ≤ 10µA
MAX13050/MAX13052/
MAX13053/MAX13054
Industry-Standard High-Speed CAN
Transceivers with ±80V Fault Protection
www.maximintegrated.com Maxim Integrated
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