New-Tech Europe Magazine | Q3 2020

Figure 4: Next Generation 45 GHz Broadband Equalizers Optimized bonding (BLACK) vs original Bonding (RED)

insertion loss and return loss were measurably improved up to the 50 GHz band edge utilize a Patent Pending wirebond technique. This same approach was used in a new family of DC to 45 GHz slope equalizers EQY-x-453+ (Figure 4.). In these new equalizer products, the optimized bonding delivered more consistent return loss across the band, as well as improved monotonicity of the response. Lead Frame Optimization The package anchor point for the bondwire connection is equally important to the bond pad design on the die itself. This is where in- house packaging capability was of great benefit. We optimized the size and location of the leadframe

RF bondpads (relative to the other package connections) we quickly created prototypes to validate the performance improvements. Another improvement was in the overall design of the leadframe itself. Specifically, the EM simulations showed unwanted coupling between pins, even if unconnected internally or grounded externally. This coupling substantially degraded high frequency response. The EP2KA+ two-way MMIC splitter (10 to 43.5 GHz) is a perfect example of this pin optimization approach. We started with the same package as the MGVA-82+ (DC to 5.2 GHz dual matched amplifier), and by selectively removing pins from the leadframe (Figure 5.), were able to measurably improve the input

to output isolation, as well as the amplitude and phase unbalance. The leadframe bond pad optimization also improved input/output VSWR to better than 2:1 over the majority

of the band (Figure 6.). Non-RF Interconnects

At mmW frequencies, confining the RF signal, and reducing unwanted coupling is a challenge, as described above. While the RF connections are often the focus of the design, the non-RF connections, if overlooked, also contribute to performance degradation at higher frequencies. There are times when these package contacts can’t be eliminated, so Mini- Circuits developed a patent-pending technique which takes advantage of these extra connections to isolate

Figure 5: MGVA-62+ Matched Amplifier pin configuration vs. EP2KA+ Splitter pin configuration

Figure 6: EP2KA+ VSWR

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