Data Sheet

ADL8103

APPLICATIONS INFORMATION

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Rev. 0 | 22 of 25

The basic connections for operating the ADL8103 over the speci-

fied frequency range are shown in Figure 91. No external biasing

inductor is required, allowing the 5 V supply to be connected

to the VDD pin. It is recommended to use 0.1 µF and 100 pF

power supply decoupling capacitors. The power supply decoupling

capacitors shown in Figure 91 represent the configuration used to

characterize and qualify the ADL8103.

To set IDQ, connect a resistor (R2) between the RBIAS and VDD

pins as shown in Figure 91. A default value of 698 Ω is recommend-

ed, which results in a nominal IDQ of 100 mA. Table 9 shows how

the IDQ and IDQ_AMP varies vs. the RBIAS. The RBIAS pin also draws

a current that varies with the value of RBIAS (see Table 9). Do not

leave the RBIAS pin open.

Figure 91. Typical Application Circuit

RECOMMENDED BIAS SEQUENCING

Correct sequencing of the DC and RF power is required to safely

operate the ADL8103. During power up, apply VDD before the RF

power is applied to RFIN, and during power off, remove the RF

power from RFIN before VDD is powered off.

Table 9. Recommended Bias Resistor Values for VDD = 5 V

RBIAS (Ω)

Total Current,

IDQ (mA)

Amplifier

Current, IDQ_AMP

(mA)

RBIAS Current, IRBIAS

(mA)

1690

60

57.80

2.20

1300

70

67.24

2.76

1020

80

76.65

3.35

845

90

86.09

3.91

698

100

95.46

4.54

576

110

104.8

5.20

487

120

114.15

5.85

Table 10. Recommended Bias Resistor Values for VDD = 3 V

RBIAS (Ω)

Total Current, IDQ

(mA)

Amplifier

Current, IDQ_AMP

(mA)

RBIAS Current,

IRBIAS (mA)

649

50

47.52

2.48

470

60

56.87

3.13

348

70

66.22

3.72

255

80

75.54

4.46

191

90

84.83

5.17

140

100

94.18

5.82

Table 11. Recommended Bias Resistor Values for Various Supply Voltages,

IDQ = 100 mA

RBIAS (Ω)

VDD (V)

Amplifier

Current, IDQ_AMP

(mA)

RBIAS Current,

IRBIAS (mA)

140

3

94.10

5.90

470

4

94.80

5.20

698

5

95.46

4.54

1100

6

96.6

3.90