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©2011-2012 Peregrine Semiconductor Corp. All rights reserved.

Product Brief

PE42556

Power Handling Scaling with Frequency

0

5

10

15

20

25

30

1

10

100

1000

Freq (kHz)

-12

-10

-8

-6

-4

-2

0

2

4

6

8

2.9

3

3.1

3.2

3.3

3.4

3.5

3.6

Vdd (V)

Upper Power Limit

Figure 5 shows how the power limit in Figure 4 will

increase with frequency. As the frequency

increases, the contours and Maximum Power

Limit Curve will increase with the increase in

power handling shown on the curve.

Figure 4. Maximum Operating Power Limit

vs. Vdd and Input Power @ 9 kHz

Figure 5. Operating Power Offset vs.

Frequency (Normalized to 9 kHz)

Figure 4 provides guidelines of how to adjust the

Vdd and Input Power to the PE42556 device. The

upper limit curve represents the maximum Input

Power vs Vdd recommended for this part at low

frequencies only. Please consult Table 3 for the

1 MHz ≤13.5 GHz range.

To allow for sustained operation under any load VSWR condition, max power

should be kept 6dB lower than max power in 50 Ohm.

Power Handling Examples

Example 1: Maximum power handling at 100 kHz,

Z = 50 ohms, VSWR 1:1, and Vdd = 3V



The power handling offset for 100 kHz from

Fig. 5 is 7 dB



The max power handling at Vdd = 3V is 5.5 dB

from Fig. 4



Derate power under mismatch conditions



Total maximum power handling for this

example is 7 dB + 5.5 dB = 12.5 dBm