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TRANSMIT LEVEL CONTROL

−3

−2

−1

0

1

0

2

4

6

8

10

12

14

16

18

20

22

24

26

28

30

Gain State

−80

−70

−60

−50

−40

−30

−20

−10

0

Pout

LO1 Leakage

at IF2 port

Gain Deviation

from ideal

IMD Level with two input tones at 250 mVpp diff. each

T=25

−70

−60

−50

−40

−30

−20

−10

−40

−30

−20

−10

0

10

20

30

40

50

60

70

80

90

Temperature (

−4

−3

−2

−1

0

1

2

Pout with

Vin =500mVppdiff

LO1 Leakage

at IF2 port

IMD Level with two input tones

at 250mVppdiff each

All measurements are

made at Max. Gain

TRF1121

TRF1221

SLWS170A – APRIL 2005 – REVISED DECEMBER 2005

The TRF1121 / TRF1221 offer 32 dB of gain control through a five wire parallel bus. When driven with a

500-mVpp differential baseband IF signal, the transmit level can be programmed between –32 dBm and 0 dBm

in 1 dB steps.

Figure 4. Output Power, LO Leakage and IMD Level vs Gain State

Figure 5. Power Level, IMD and LO1 Leakage Variation vs Temperature at Maximum Gain Setting

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