Texas Instruments AN-1574 LM5073, User Manual, Page: 7 / 19

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Configuration 4: Simple Non-Isolated PD Application
Table 4. Jumper Positions of Configuration 3 (continued)
Jumper Function
Jumper pins short when on-board dc-dc converter is used.
JMP9, JMP10, JMP11, JMP12, JMP13
Jumper pins open when on-board dc-dc converter is used.
Note:
1.The sum of C1 and C2 comprises the valid signature capacitance. In practice, this configuration can delete C2 and
change C1 to 0.1µF.
2. R6 may need to be installed for classification other than the default Class 0. Refer to LM5073 datasheet for R6
selection.
3. The installed R7 (15.8k) is intended for high power PD applications, which sets the dc current limit to 800 mA. For
fully compliant applications, R7 may need to be removed or replaced in order to limit the dc current per IEEE 802.3af.
Refer to LM5073 datasheet for R7 selection.
Figure 4. IEEE 802.3af Fully Compliant PD Interface with Front Aux Power Support
12 Configuration 4: Simple Non-Isolated PD Application
Figure 5 shows a simple non-isolated PD application using the onboard buck regulator. The following table
shows the jumper positions for this configuration. See the previous note about the onboard buck regulator.
Table 5. Jumper Positions of Configuration 4
Jumper Function
JMP4, JMP5 Pins 2 and 3 short, Pin 1 open.
JMP6 All three pins short together.
JMP7 Pins open.
JMP8 All three pins open.
JMP9, JMP11, JMP12, JMP13 Jumper pins short.
Other Jumpers Not relevant.
7 SNVA214A – April 2007 – Revised April 2013 AN-1574 LM5073 Evaluation Board
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