Power Supplies and Bypassing
CAN transceiver. Two bypass
capacitors (with values between
0.01 and 0.1 µF) are required and
should be located as close as
possible to the input and output
power-supply pins of the HCPL-
0710. For each capacitor, the
total lead length between both
ends of the capacitor and the
power supply pins should not
exceed 20 mm. The bypass capac-
itors are required because of the
high-speed digital nature of the
signals inside the optocoupler.
The recommended DeviceNet
application circuit is shown in
Figure 21. Since the HCPL-0710
is fully compatible with CMOS
logic level signals, the optocoup-
ler is connected directly to the
GALVANIC
ISOLATION
BOUNDARY
ISO 5 V
5 V
LINEAR OR
SWITCHING
REGULATOR
V
V
V
DD2
1
2
8
7
DD1
+
+
0.01
µF
TX0
IN
HCPL-0710
V
CC
5 V+
TxD
Rs
V
O
0.01 µF
3
4
6
5
CANH
4 CAN+
3 SHIELD
2 CAN–
1 V–
82C250
GND
GND
GND
+
1
2
2
C4
0.01 µF
CANL
REF
GND
VREF
RXD
GND
GND
5
6
4
3
1
C1
0.01 µF
500 V
0.01
µF
D1
R1
1 M
RX0
V
O
30 V
HCPL-0710
V
0.01 µF
7
8
2
1
IN
V
V
DD1
DD2
ISO 5 V
5 V
Figure 21. Recommended DeviceNet Application Circuit.
PROFIBUS USER:
CONTROL STATION
(CENTRAL PROCESSING)
OR FIELD DEVICE
tion of a field automation unit
(control or central processing
station) or a field device to the
transmission medium. The PBC
consists of the line transceiver,
optical isolation, frame character
transmitter/receiver (UART), and
the FDL/APP processor with the
interface to the PROFIBUS user.
Implementing PROFIBUS
with the HCPL-0710
An acronym for Process Fieldbus,
PROFIBUS is essentially a
USER INTERFACE
FDL/APP
PROCESSOR
twisted-pair serial link very
similar to RS-485 capable of
achieving high-speed communi-
cation up to 12 MBd. As shown in
Figure 22, a PROFIBUS Control-
ler (PBC) establishes the connec-
UART
PBC
OPTICAL ISOLATION
TRANSCEIVER
MEDIUM
Figure 22. PROFIBUS Controller
(PBC).
AGILENT [ AGILENT TECHNOLOGIES, LTD. ]
