Datasheet

13
Implementing DeviceNet and SDS with the HCPL-x710
With transmission rates up to 1 Mbit/s, both DeviceNet
and SDS are based upon the same broadcast-oriented,
communications protocol — the Controller Area
Network (CAN). Three types of isolated nodes are rec-
ommended for use on these networks: Isolated Node
Powered by the Network (Figure 19), Isolated Node
with Transceiver Powered by the Network (Figure 20),
and Isolated Node Providing Power to the Network
(Figure 21).
Figure 18. Typical DeviceNet node.
Figure 19. Isolated node powered by the network.
Isolated Node Powered by the Network
This type of node is very exible and as can be seen in
Figure 19, is regarded as “isolated” because not all of its
components have the same ground reference. Yet, all
components are still powered by the network. This node
contains two regulators: one is isolated and powers the
CAN controller, node-specic application and isolated
(node) side of the two optocouplers while the other is
non-isolated. The non-isolated regulator supplies the
transceiver and the non-isolated (network) half of the
two optocouplers.
NODE/APP SPECIFIC
uP/CAN
HCPL
x710
HCPL
x710
TRANSCEIVER
LOCAL
NODE
SUPPLY
5 V REG.
NETWORK
POWER
SUPPLY
V+ (SIGNAL)
V– (SIGNAL)
V+ (POWER)
V– (POWER)
GALVANIC
ISOLATION
BOUNDARY
AC LINE
DRAIN/SHIELD
SIGNAL
POWER
HCPL-0710 fig 17
NODE/APP SPECIFIC
uP/CAN
HCPL
x710
HCPL
x710
TRANSCEIVER
REG.
V+ (SIGNAL)
V– (SIGNAL)
V+ (POWER)
V– (POWER)
GALVANIC
ISOLATION
BOUNDARY
DRAIN/SHIELD
SIGNAL
POWER
HCPL-0710 fig 18
ISOLATED
SWITCHING
POWER
SUPPLY
NETWORK
POWER
SUPPLY