Specifications

PL 3120/PL 3150/PL 3170 Power Line Smart Transceiver Data Book 167
The performance of this power supply is somewhat sensitive to layout. Minimizing the length of the net from the
Drain of the VIPer20A IC is of particular importance in controlling conducted emissions. In order to reduce the time
required to successfully implement this supply, a recommended layout is provided below.
Figure 5.8 Recommended Layout of the Pre-Verified Isolated Switching Supply
While each new product must be verified for regulatory compliance and communication performance, using this
supply simplifies the development task since an instance of this design has been pre-verified. This supply was tested
in combination with PL 3120 Smart Transceiver reference design #1217 from Appendix A and the isolated Line-to-
Neutral coupling circuit Example 2 from Chapter 4. This combination passed EN50065-1 and FCC regulations for
conducted emissions with 8dB of margin when the output of the supply was floating (not connected to earth ground).
In applications requiring a grounded output, adding the optional common mode choke provides a passing result. This
supply and PL reference design was also verified to pass all of the communication performance tests of Chapter 7. In
addition, this supply and coupling circuit combination passed the surge tests documented for the Example 2 coupling
circuit in Table 4.14 in Chapter 4.