IDTF1241 Datasheet, PDF (1/20 Pages) Integrated Device Technology – Dual IF Digital Variable Gain Amplifier

Dual IF Digital Variable Gain Amplifier
GENERAL DESCRIPTION
The IDTF1241 (1 dB steps) is an IF VGA for Diversity
Basestation receivers. The device offers significantly
better Noise and Distortion performance than currently
available devices. It is packaged in a compact 5x5
Thin QFN with 200 ohm differential input and output
impedances for ease of integration into the receiver
lineup.
COMPETITIVE ADVANTAGE
The IDTF1241 IF VGA improves system Signal-to-Noise
Ratio (SNR), especially at lower gain settings. Via IDT’s
proprietary FlatNoise^TM technology both IP3_O & NF are
kept virtually flat while gain is backed
off, enhancing SNR significantly under
high level interferer conditions, and
greatly benefiting 2G/3G/4G Multi-
FlatNoise^TTMM
Carrier IF sampling receivers.
The fast-settling gain step of 1 dB coupled with pinpoint
accuracy allow for SNR to be maximized further by
targeting the minimum necessary gain in small, accurate
increments.
See the ‘Applications Information’ section starting on
Page 17 for more details of the benefits of the F1241 in
IF sampling receivers.
PART# MATRIX
Part#
F1241
F1240
Range /
Step
20 to -11
1.0
20 to -11.5
0.5
IP3O
IF freq
range
NF
48 10 - 500 4
47 10 - 500 4
Pinout
Compatibility
ADI
TI (NSM)
ORDERING INFORMATION
Omit IDT
prefix
0.8 mm height ^{Tape &}
package
Reel
IDTF1241NBGI8
RF product Line
Green
Industrial
Temp range
IDTF1241
DATASHEET
10 – 500 MHz IDTF1241NBGI
FEATURES
• Ideal for systems with high SNR requirements
• 20 dB typical Maximum Gain
• 5-bit, 1 dB step, 31 dB gain control range
• Excellent Noise Figure = 4.0 dB
• 5mm x 5mm 32 pin package
• 200 Ω Differential Matched Input
• 200 Ω Differential Matched Output
• No termination resistors required
• NF degrades just 1.3 dB @ 10 dB below Max Gain
• 10 MHz – 500 MHz frequency range
• Ultra-Linear: IP3_O +48 dBm typical
• Excellent 2^nd Harmonic Rejection < -80 dBc
• Parallel Control
• External current setting resistors
• Very fast settling < 15 nsec
• Individual Power Down Modes
• Extremely Low Power: 80 mA / Chan
APPLICATIONS
• Base Station 2G, 3G, 4G, TDD radiocards
• Repeaters and E911 systems
• Digital Pre-Distortion
• Point to Point Infrastructure
• Public Safety Infrastructure
• WIMAX Receivers and Transmitters
• Military Systems, JTRS radios
DEVICE BLOCK DIAGRAM
ATTN
In A
Gain ¹⁰
Control
VCC
Decode
Logic
ATTN
In B
AMP
out A
Bias
Control
VCC
STBYA
STBYB
2
ISET
AMP
out B
IDT FlatNoise^TM IF VGA
1
Rev O Nov 2012