LMH0307 Datasheet, PDF (7/14 Pages) National Semiconductor (TI) – 3 Gbps HD/SD SDI Dual Cable Driver with Cable Detect

Application Information
Figure 1 shows the application circuit for the LMH0307.
FIGURE 1. Application Circuit
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COMMUNICATING WITH MULTIPLE LMH0307 CABLE
DRIVERS VIA THE SMBus
A common application for the LMH0307 will utilize multiple
cable driver devices. Even though the LMH0307 devices all
have the same default SMBus device ID (address), it is still
possible for them share the SMBus signals as shown in
Figure 2. A third signal is required from the host to the first
device. This signal acts as a “Enable / Reset” signal. Addi-
tional LMH0307s are controlled from the upstream device. In
this control scheme, multiple LMH0307s may be controlled
via the two-wire SMBus and the use of one GPO (General
Purpose Output) signal. Other SMBus devices may also be
connected to the two wires, assuming they have their own
unique SMBus addresses.
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