MAX13041_08 Datasheet, PDF (12/20 Pages) Maxim Integrated Products – ±80V Fault-Protected High-Speed CAN Transceiver with Low-Power Management and Wake-On CAN

±80V Fault-Protected High-Speed CAN Transceiver
with Low-Power Management and Wake-On CAN
In the lowest-power mode, the MAX13041 disables exter-
nal voltage regulators to provide a sleep mode for the
entire node. The MAX13041 restores power to the node
upon a logic transition on WAKE or detection of CAN
bus activity.
The operating mode is determined by an internal state
machine controlled by EN and STB, as well as several
internal flags (see Table 1 and Figure 4).
Normal Mode
The MAX13041 provides full bidirectional CAN commu-
nication in normal mode. Drive TXD to transmit data on
the differential CAN bus lines CANH and CANL. The
CAN bus state is presented on RXD, a level-shifted
logic output. SPLIT is biased to V_CC/2 to allow CAN bus
common-mode stabilization. INH is logic-high, enabling
one or more external voltage regulators (see Table 1).
PWON/Listen-Only Mode
In PWON/listen-only mode, the CAN transmitter is dis-
abled. The CAN receiver remains active and the CAN
bus state is presented on RXD, a level-shifted logic out-
put. As in normal mode, SPLIT is biased to V_CC/2 to
allow CAN bus common-mode stabilization. INH is
logic-high, enabling one or more external voltage regu-
lators (see Table 1).
Standby Mode
Standby mode is the first low-power operating mode.
The CAN transmitter and receiver are disabled, and a
low-power receiver is enabled to monitor the CAN bus
for activity. To reduce power consumption, common-
mode stabilization is disabled. SPLIT becomes high
impedance, and CANH and CANL are biased to
ground by the termination resistors. INH remains logic-
high, enabling one or more external voltage regulators
(see Table 1).
Go-to-Sleep Command Mode
Go-to-sleep command mode is part of the controlled
sequence for entering sleep mode. The MAX13041
remains in go-to-sleep command mode for a hold time of
56µs (max), and subsequently enters sleep mode if no
wake events are detected. During the hold time, if the
state of EN or STB changes, or if the UV_BAT, PWON, or
wake-up flags are set, the go-to-sleep sequence is
aborted. During go-to-sleep command mode, functionali-
ty is the same as in standby mode.
Sleep Mode
Sleep mode is the lowest-power operating mode. The
CAN transmitter and receiver are disabled, and a low-
power receiver is enabled to monitor the CAN bus for
Table 1. Operating Modes
CONTROL PINS
STB
EN
X
X
L
L
L
H
H
L
H
H
UV_NOM
SET
CLEAR
CLEAR
CLEAR
CLEAR
CLEAR
INTERNAL FLAGS
UV_BAT
X
PWON, WAKE-UP
X
EITHER FLAG SET
SET
BOTH FLAGS CLEAR
EITHER FLAG SET
CLEAR
BOTH FLAGS CLEAR
EITHER FLAG SET
CLEAR
BOTH FLAGS CLEAR
CLEAR
X
CLEAR
X
OPERATING MODE
SLEEP (Notes 6, 7)
STANDBY
STANDBY FROM ANY OTHER MODE
STANDBY
NO CHANGE FROM SLEEP MODE
STANDBY FROM ANY OTHER MODE
STANDBY
NO CHANGE FROM SLEEP MODE
GO-TO-SLEEP COMMAND MODE FROM
ANY OTHER MODE (Note 7)
PWON/LISTEN-ONLY
NORMAL (Note 9)
INH
FLOATING
H
H
H
FLOATING
H
H
FLOATING
H
H
H
Note 6: Setting the PWON or wake-up flags clears UVNOM flag.
Note 7: The MAX13041 enters sleep mode from any other mode when UVNOM is set. INH becomes high impedance.
Note 8: When go-to-sleep command mode is selected for longer than tH(MIN), the MAX13041 enters sleep mode.
INH becomes high impedance.
Note 9: PWON and wake-up flags are cleared upon entering normal mode.
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