Data Sheet

ADL8122

APPLICATIONS INFORMATION

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Rev. 0 | 26 of 28

OVERDRIVE RECOVERY OPTIMIZATION

The overdrive recovery performance of the 10 MHz to 10 GHz

circuit (see Figure 94) can be improved by adjusting the C1 and

L1 values shown in Figure 99. Figure 82 is the overdrive recovery

time performance comparison of the baseline ADL8122-EVALZ

configuration vs. the optimized ADL8122-EVALZ. The reduced val-

ue of the input DC blocking capacitor, C1, has the most impact on

the improved overdrive recovery. However, by using a smaller C1

value, the minimum frequency of operation was adjusted from 10

MHz to 350 MHz. For optimum performance, the VDD2 voltage (5

V) must come from a separate supply other than VDD (5 V). The

bypass capacitor on VDD2 is incorporated to limit any power supply

related noise from entering the device.

Figure 98. Gain and Return Loss vs. Frequency for ADL8122-EVALZ

Overdrive Recovery Time Optimized Circuit, 10 MHz to 12 GHz,

VDD = 5 V, RBIAS = 620 Ω

Figure 99. Application Circuit for ADL8122-EVALZ Optimized Overdrive Recovery Time