100 MHz to 4000 MHz

RF/IF Digitally Controlled VGA

ADL5240

Rev. 0

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FEATURES

Operating frequency from 100 MHz to 4000 MHz

Digitally controlled VGA with serial and parallel interfaces

6-bit, 0.5 dB digital step attenuator

31.5 dB gain control range with ±0.25 dB step accuracy

Gain block amplifier specifications

Gain: 19.7 dB at 2.14 GHz

OIP3: 41.0 dBm at 2.14 GHz

P1dB: 19.5 dBm at 2.14 GHz

Noise figure: 2.9 dB at 2.14 GHz

Gain block or digital step attenuator can be first

Single supply operation from 4.75 V to 5.25 V

Low quiescent current of 93 mA

Thermally efficient, 5 mm × 5 mm, 32-lead LFCSP

The companion ADL5243 integrates a ¼ W driver amplifier to

the output of the gain block and DSA

APPLICATIONS

Wireless infrastructure

Automated test equipment

RF/IF gain control

GENERAL DESCRIPTION

The ADL5240 is a high performance, digitally controlled variable

gain amplifier (VGA) operating from 100 MHz to 4000 MHz.

The VGA integrates a high performance, 20 dB gain, internally

matched amplifier (AMP) with a 6-bit digital step attenuator

(DSA) that has a gain control range of 31.5 dB in 0.5 dB steps

with ±0.25 dB step accuracy. The attenuation of the DSA can be

controlled using a serial or parallel interface.

Both the gain block and DSA are internally matched to 50 Ω at

their inputs and outputs and are separately biased. The separate

bias allows all or part of the ADL5240 to be used, which facilitates

easy reuse throughout a design. The pinout of the ADL5240 also

enables either the gain block or DSA to be first, giving the VGA

maximum flexibility in a signal chain.

The ADL5240 consumes just 93 mA and operates from a single

supply ranging from 4.75 V to 5.25 V. The VGA is packaged in a

thermally efficient, 5 mm × 5 mm, 32-lead LFCSP and is fully

specified for operation from −40°C to +85°C. A fully populated

evaluation board is available.

FUNCTIONAL BLOCK DIAGRAM

ADL5240

AMP

9

10

11

12

13

14

15

16

SERIAL/PARALLEL INTERFACE

24

VDD

23

NC

22

NC

21

DSAOUT

20

NC

19

NC

18

NC

17

NC

0.5dB

1dB

2dB

4dB

8dB

16dB

32

31

30

29

28

27

26

25

1

VDD

2

NC

3

NC

4

DSAIN

5

NC

6

NC

7

NC

8

NC

Figure 1.