Rohm LAPIS ML7436N, Hardware Design Manual

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ML7436N LSI Hardware Design Manual
FEXL7436NDG-01
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Table 7.2
shows the resister and capacitor values of the equivalent circuit on the typical frequency.
Table 7.2 Resister and capacitor values of the equivalent circuit
Frequency[MHz] Rlna[Ω] Clna[pF]
433 881 1.51
868 563 1.53
920 549 1.55
7.1.1.
Connection of coupling capacitor
Figure 7.4
shows that the connection of enough AC coupling capacitor Cac(100pF) is connected to RF_LNA_IN1 pin.
RF_LNA_IN1 pin is biased to the stable DC voltage by the internal circuit when the IC is the reception state. Cac
causes that RF_LNA_IN1 pin is open state on DC. The DC voltage is not influenced by the matching calculation. Cac
does not influence the matching value on the high frequency range, because of enough Cac capacitor.
Figure 7.4
Addition of AC coupling capacitor Cac