Datasheet

LTC2875
18
Rev A
For more information www.analog.com
APPLICATIONS INFORMATION
Figure14. Network for IEC Level 4 Protection Against Surge, EFT and ESD
DeviceNet Compatibility
DeviceNet is a network standard based on the CAN bus.
The DeviceNet standard places requirements on the trans-
ceiver that exceed those of the ISO 11898-2 standard. The
LTC2875 meets the following DeviceNet requirements:
PARAMETER DeviceNet
REQUIREMENT
ISO
11898-2
REQUIREMENT
LTC2875
Number of Nodes 64 N/A 166
Minimum Differential
Input Resistance
20kΩ 10kΩ 50kΩ
Differential Input
Capacitance
25pF (Max) 10pF (Nom) 8.4pF (Typ)
Bus Pin Voltage Range
(Survivable)
–25V to 18V –3V to 16V
(for 12V
Battery)
–60V to 60V
Bus Pin Voltage Range
(Operation)
–5V to 10V –2V to 7V –36V to 36V
(V
CC
= 5V)
Connector Mis-Wiring
Tests, All Pin-Pin
Combinations
±18V N/A ±60V
(See Below)
T
ransmitter
Propagation Delay
120ns (Max) N/A 120ns
(V
CC
= 5V)
Receiver
Propagation Delay
130ns
(Max) N/A 65ns
(V
CC
= 5V)
DeviceNet employs a 5-pin connector with conductors
for Power
+
, Power
–
, CANH, CANL, and Drain. The power
is 24V DC, and the Drain wire is connected to the cable
shield for shielded cables. DeviceNet devices that are
powered from the 24V DC line voltage contain a step-
down regulator to power the CAN transceiver and associ-
ated circuitry, and blocking diodes to prevent damage in
case of power polarity reversal.
The DeviceNet mis-wiring tests involve connecting an
18V supply to each of the 20 possible pin pair/polarity
combinations on the 5-pin connector. The ±60V tolerance
of the LTC2875 with V
CC
and/or GND open or grounded
ensure that the LTC2875 will pass all the mis-wiring tests
without damage as long as its V
CC
pin is protected from
overvoltage and reverse polarity by other circuitry in the
DeviceNet device.
2875 F14
CANL
V
CC
TVS
GDT
TBU
TBU
MOV
GDT: BOURNS 2031-15T-SM; 150V GAS DISCHARGE TUBE
TBU: BOURNS TBU-CA050-300-WH; 500V TRANSIENT BLOCKING UNIT
MOV: BOURNS MOV-7D201K; 200V 13J METAL OXIDE VARISTOR
TVS: BOURNS CDSOD323-T36SC; 36V BIDIRECTIONAL TVS DIODE
MOV
CANH
RXD
TXD
R
T
GND
RS
LTC2875
GDT
CANH_EXTERNAL
GND
CANL_EXTERNAL
TVS
Downloaded from Arrow.com.Downloaded from Arrow.com.Downloaded from Arrow.com.Downloaded from Arrow.com.Downloaded from Arrow.com.Downloaded from Arrow.com.Downloaded from Arrow.com.Downloaded from Arrow.com.Downloaded from Arrow.com.Downloaded from Arrow.com.Downloaded from Arrow.com.Downloaded from Arrow.com.Downloaded from Arrow.com.Downloaded from Arrow.com.Downloaded from Arrow.com.Downloaded from Arrow.com.Downloaded from Arrow.com.Downloaded from Arrow.com.