LMH6521 Datasheet, PDF (2/24 Pages) Texas Instruments – LMH6521 High Performance Dual DVGA

LMH6521
September 14, 2011
High Performance Dual DVGA
General Description
The LMH6521 contains two high performance, digitally con-
trolled variable gain amplifiers (DVGA).
Both channels of the LMH6521 have an independent, digitally
controlled attenuator followed by a high linearity, differential
output amplifier. Each block has been optimized for low dis-
tortion and maximum system design flexibility. Each channel
has a high speed power down mode.
The internal digitally controlled attenuator provides precise
0.5dB gain steps over a 31.5dB range. Serial and parallel
programming options are provided. Serial mode program-
ming utilizes the SPI™ interface. A Pulse mode is also offered
where simple up or down commands can change the gain one
step at a time.
The output amplifier has a differential output allowing 10V_PPD
signal swings on a single 5V supply. The low impedance out-
put provides maximum flexibility when driving filters or analog
to digital converters.
Features
■ ^{OIP3 of 48.5 dBm at 200 MHz}
■ ^{Maximum voltage gain of 26 dB}
■ ^{Gain range of 31.5 dB with 0.5dB step size}
■ ^{Channel Gain Matching of ±0.04 dB}
■ ^{Noise figure of 7.3 dB at maximum gain}
■ ^{-3 dB bandwidth of 1200 MHz}
■ ^{Low power dissipation}
■ ^{Independent channel power down}
■ ^{Three gain control modes:}
•Parallel interface
•Serial interface (SPI)
•Pulse mode interface
■ ^{Temperature Range –40°C to +85°C}
■ ^{Thermally enhanced, 32–Pin LLP package}
Applications
■ ^{Cellular base stations}
■ ^{Wideband and narrowband IF sampling receivers}
■ ^{Wideband direct conversion}
■ ^{Digital pre-distortion}
■ ^{ADC driver}
Channel Matching Error (Ch A — Ch B)
0.20
2.0
0.15
1.5
0.10
Gain Matching Error
1.0
0.05
0.5
0.00
0.0
-0.05
-0.5
-0.10
-0.15
Phase Matching Error ^-1.0
-1.5
-0.20
0
-2.0
4 8 12 16 20 24 28 32
ATTENUATION (dB)
30120180
LMH6521 Block Diagram
30120102
SPI™ is a trademark of Motorola, Inc.
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