HCPL-7710-000E Datasheet, PDF (17/18 Pages) AVAGO TECHNOLOGIES LIMITED – 40 ns Propagation Delay, CMOS Optocoupler

Power Supplies and Bypassing
The recommended PROFIBUS application circuit is
shown in Figure 24. Since the HCPL-x710 are fully com-
patible with CMOS logic level signals, the optocoup ­
ler is connected directly to the 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-
x710. 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 capac­itors are
required because of the high-speed digital nature of the
signals inside the optocoupler.
Being very similar to multi-station RS485 systems, the
HCPL-061N optocoupler provides a transmit disable
function which is necessary to make the bus free after
each master/slave transmission cycle. Specifically, the
HCPL-061N disables the transmitter of the line driver
by putting it into a high state mode. In addition, the
HCPL-061N switches the RX/TX driver IC into the listen
mode. The HCPL-061N offers HCMOS compatibility and
the high CMR performance (1 kV/µs at V_CM = 1000 V)
essential in industrial communication interfaces.
GALVANIC
ISOLATION
BOUNDARY
5V
ISO 5 V
8 V_DD2
V_DD1 1
0.01 µF
Rx
7
V_IN 2
HCPL-x710
6 V_O
3
0.01
µF
5 GND₂
GND₁ 4
5V
ISO 5 V
1 V_DD1
V_DD2 8
0.01
Tx
2 V_IN
7
µF
0.01 µF
HCPL-x710
3
V_O 6
4 GND₁
GND₂ 5
0.01
µF
ISO 5 V
1R
8
V_CC
SN75176B
4
D
3 _DE
2 _RE
GND
5
A6
RT
B7
0.01 µF
+
SHIELD
–
1M
Tx ENABLE
5V
1, 0 kΩ
ISO 5 V
1
V_CC 8
2 ANODE
3 CATHODE
V_{E 7}
V_O 6
0.01
µF
4
GND 5
680 Ω
HCPL-061N
Figure 24. Recommended PROFIBUS application circuit.
HCPL-0710 fig 23
17