AD8353

Rev. B | Page 14 of 16

APPLICATIONS

The AD8353 RF gain block can be used as a general-purpose,

fixed gain amplifier in a wide variety of applications, such as a

driver for a transmitter power amplifier (see Figure 37). Its

excellent reverse isolation also makes this amplifier suitable for

use as a local oscillator buffer amplifier that would drive the

local oscillator port of an upconverter or downconverter mixer

(see Figure 38).

AD8353

HIGH POWER

AMPLIFIER

Figure 37. AD8353 as a Driver Amplifier

AD8353

MIXER

LOCAL OSCILLATOR

Figure 38. AD8353 as a LO Driver Amplifier

LOW FREQUENCY APPLICATIONS BELOW 100 MHz

The AD8353 RF gain block can be used below 100 MHz. To

accomplish this, the series dc blocking capacitors, C1 and C2,

need to be changed to a higher value that is appropriate for the

desired frequency. C1 and C2 were changed to 0.1 μF to

accomplish the sweep in Figure 39.

21.0

20.5

20.0

19.5

19.0

18.5

18.0

17.5

17.0

16.5

16.0

dB-S21

CH 1: START 300.000kHz

STOP 100.000MHz

Figure 39. Low Frequency Application from

300 kHz to 100 MHz at 5 V VPOS, −12 dBm Input Power