4

TEST CIRCUIT

1 000 pF

1 000 pF

1 000 pF

L

4

6

1

2, 3, 5

50

Ω

50

Ω

OUT

IN

Components of test circuit for

measuring electrical characteristics

Example of actural application components

TYPE

VALUE

TYPE

VALUE

OPERATING FREQUENCY

Capacitor

1 000 pF

Chip capacitor

1 000 pF

100 MHz or higher

L

Bias Tee

1 000 nH

L

Chip inductor

100 nH

100 MHz or higher

Bias Tee

1 000 pF

10 nH

1.0 GHz or higher

INDUCTOR FOR THE OUTPUT PIN

The internal output transistor of this IC consumes 20 mA, to output medium power. To supply current for output

listed above.

The inductor has both DC and AC effects. In terms of DC, the inductor biases the output transistor with minimum

voltage drop to output enable high level. In terms of AC, the inductor make output-port impedance higher to get

enough gain. In this case, large inductance and Q is suitable.

for the input and output pins.

The coupling capacitors, connected to the input and output pins, are used to cut the DC and minimize RF serial

impedance. Their capacitance are therefore selected as lower impedance against a 50

Ω load. The capacitors thus

perform as high pass filters, suppressing low frequencies to DC.

To obtain a flat gain from 100 MHz upwards, 1 000 pF capacitors are used in the test circuit. In the case of under

10 MHz operation, increase the value of coupling capacitor such as 10 000 pF. Because the coupling capacitors are

determined by equation, C = 1/(2

πRfc).