Datasheet LTC6412 (Analog Devices)
| Manufacturer | Analog Devices |
| Description | 800MHz, 31dB Range Analog-Controlled VGA |
| Pages / Page | 24 / 1 — FEATURES. DESCRIPTION. 800MHz –3dB Small-Signal Bandwidth. … |
| File Format / Size | PDF / 505 Kb |
| Document Language | English |
FEATURES. DESCRIPTION. 800MHz –3dB Small-Signal Bandwidth. Continuously-Adjustable Gain Control
Model Line for this Datasheet
Text Version of Document
LTC6412 800MHz, 31dB Range Analog-Controlled VGA
FEATURES DESCRIPTION
n
800MHz –3dB Small-Signal Bandwidth
The LTC®6412 is a fully differential variable gain amplifi er n
Continuously-Adjustable Gain Control
with linear-in-dB analog gain control. It is designed for n
–14dB to +17dB Linear-in-dB Gain Range
AC-coupled operation in IF receiver chains from 1MHz n
35dBm OIP3 at 240MHz Across All Gain Settings
to 500MHz. The part has a constant OIP3 across a wide n
10dB Noise Figure at Maximum Gain
output amplitude range and across the 31dB gain control n
(IIP3 – NF) = +8dBm at 240MHz Across All Gains
range. The output noise (NF + Gain) is also fl at versus gain n 2.7nV/√Hz Input Referred Noise to provide a uniform spurious-free dynamic range (SFDR) n Differential Inputs and Outputs >120dB over the full gain control range at 240MHz. n 50Ω Input Impedance Across all Gains The LTC6412 is ideal for interfacing with the LT®5527 and n Single Supply Operation from 3V to 3.6V LT5557 downconverting mixers, LTC6410-6 IF amplifi er n 110mA Supply Current and the LTC6400/LTC6401/LTC6416 ADC drivers for use n 4mm × 4mm × 0.75mm 24-Pin QFN Package in 12-, 14-, and 16-bit ADC applications.
APPLICATIONS
The LTC6412 recovers quickly from an overdrive condition, and the EN pin allows for a fast output signal disable to n IF Signal Chain Automatic Gain Control (AGC) protect sensitive downstream components. Asserting the n 2.5G and 3G Cellular Basestation Transceivers SHDN pin reduces the current consumption below 1mA n WiMAX, WiBro, WLAN Receivers for power-down or sleep modes. n Satellite and GPS Receiver IF L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners.
TYPICAL APPLICATION 3.3V Fully Differential 240MHz IF Receiver Chain with 31dB Gain Control VGA Gain vs Frequency Over Gain Control Range
3.3V 20 3.3V GMAX 1nF 0.1μF 10 CC 3.3V V 3.3V 10nF 180nH 180nH BPF V +IN SHDN EN +OUT DD +IN +OUT 0 V+ A + IN IF INPUT LTC6412 0.1μF LTC6400-8 LTC2208 G VCM – GAIN (dB) REF +V A –10 G –IN V –IN IN V– –OUT –V –OUT VCM GND DECL2 0.1μF G 10nF MIN CM DECL1 GAIN CONTROL V –20 6412 TA01 GND (+ SLOPE MODE) 2.2μF –30 10nF 0.1μF 0.1μF 0.1μF 1 10 100 1000 10000 FREQUENCY (MHz) 6412 G01 6412fa 1
FEATURES DESCRIPTION
n
800MHz –3dB Small-Signal Bandwidth
The LTC®6412 is a fully differential variable gain amplifi er n
Continuously-Adjustable Gain Control
with linear-in-dB analog gain control. It is designed for n
–14dB to +17dB Linear-in-dB Gain Range
AC-coupled operation in IF receiver chains from 1MHz n
35dBm OIP3 at 240MHz Across All Gain Settings
to 500MHz. The part has a constant OIP3 across a wide n
10dB Noise Figure at Maximum Gain
output amplitude range and across the 31dB gain control n
(IIP3 – NF) = +8dBm at 240MHz Across All Gains
range. The output noise (NF + Gain) is also fl at versus gain n 2.7nV/√Hz Input Referred Noise to provide a uniform spurious-free dynamic range (SFDR) n Differential Inputs and Outputs >120dB over the full gain control range at 240MHz. n 50Ω Input Impedance Across all Gains The LTC6412 is ideal for interfacing with the LT®5527 and n Single Supply Operation from 3V to 3.6V LT5557 downconverting mixers, LTC6410-6 IF amplifi er n 110mA Supply Current and the LTC6400/LTC6401/LTC6416 ADC drivers for use n 4mm × 4mm × 0.75mm 24-Pin QFN Package in 12-, 14-, and 16-bit ADC applications.
APPLICATIONS
The LTC6412 recovers quickly from an overdrive condition, and the EN pin allows for a fast output signal disable to n IF Signal Chain Automatic Gain Control (AGC) protect sensitive downstream components. Asserting the n 2.5G and 3G Cellular Basestation Transceivers SHDN pin reduces the current consumption below 1mA n WiMAX, WiBro, WLAN Receivers for power-down or sleep modes. n Satellite and GPS Receiver IF L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners.
TYPICAL APPLICATION 3.3V Fully Differential 240MHz IF Receiver Chain with 31dB Gain Control VGA Gain vs Frequency Over Gain Control Range
3.3V 20 3.3V GMAX 1nF 0.1μF 10 CC 3.3V V 3.3V 10nF 180nH 180nH BPF V +IN SHDN EN +OUT DD +IN +OUT 0 V+ A + IN IF INPUT LTC6412 0.1μF LTC6400-8 LTC2208 G VCM – GAIN (dB) REF +V A –10 G –IN V –IN IN V– –OUT –V –OUT VCM GND DECL2 0.1μF G 10nF MIN CM DECL1 GAIN CONTROL V –20 6412 TA01 GND (+ SLOPE MODE) 2.2μF –30 10nF 0.1μF 0.1μF 0.1μF 1 10 100 1000 10000 FREQUENCY (MHz) 6412 G01 6412fa 1
