LTC6400-8_15 Datasheet, PDF (1/16 Pages) Linear Technology – 2.2GHz Low Noise, Low Distortion Differential ADC Driver for DC-300MHz

LTC6400-8
2.2GHz Low Noise, Low
Distortion Differential ADC
Driver for DC-300MHz
FEATURES
n _{2.2GHz –3dB Bandwidth}
n _{Fixed Gain of 2.5V/V (8dB)}
n _{–99dBc IMD3 at 70MHz (Equivalent OIP3 = 53.4dBm)}
n _{–61dBc IMD3 at 300MHz (Equivalent OIP3 = 34.8dBm)}
n _{1nV/√Hz Internal Op Amp Noise}
n _{7.6dB Noise Figure}
n _{Differential Inputs and Outputs}
n _{400Ω Input Impedance}
n _{2.85V to 3.5V Supply Voltage}
n _{85mA Supply Current (255mW)}
n _{1V to 1.6V Output Common Mode, Adjustable}
n _{DC- or AC-Coupled Operation}
n _{Max Differential Output Swing 4.8VP-P}
n _{Small 16-Lead 3mm × 3mm × 0.75mm QFN Package}
APPLICATIONS
n _{Differential ADC Driver}
n _{Differential Driver/Receiver}
n _{Single Ended to Differential Conversion}
n _{IF Sampling Receivers}
n _{SAW Filter Interfacing}
DESCRIPTION
The LTC^®6400-8 is a high-speed differential amplifier tar-
geted at processing signals from DC to 300MHz. The part
has been specifically designed to drive 12-, 14- and 16-bit
ADCs with low noise and low distortion, but can also be
used as a general-purpose broadband gain block.
The LTC6400-8 is easy to use, with minimal support cir-
cuitry required. The output common mode voltage is set
using an external pin, independent of the inputs, which
eliminates the need for transformers or AC-coupling ca-
pacitors in many applications. The gain is internally fixed
at 8dB (2.5V/V).
The LTC6400-8 saves space and power compared to al-
ternative solutions using IF gain blocks and transformers.
The LTC6400-8 is packaged in a compact 16-lead 3mm ×
3mm QFN package and operates over the –40°C to 85°C
temperature range.
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
TYPICAL APPLICATION
3.3V
C2
0.1μF
C1
1000pF
V_IN
R1
59.0Ω
C3
0.1μF
C4
0.1μF
R2
27.4Ω
V⁺
+IN
+OUT
LTC6400-8
–IN
–OUT
V_OCM
V–
1.25V
C5
0.1μF
R_S1
15Ω
L1
R_{S2 24nH}
15Ω
COILCRAFT
0603CS
R3
100Ω
3.3V
C_F2
33pF
R_S3
10Ω
AIN^{+ VDD}
C_F1
33pF ^RS4
10Ω
C_F3
33pF
LTC2208
AIN^– _VCM
LTC2208
130Msps
16-Bit ADC
64008 TA01a
Equivalent Output IP3 vs Frequency
70
(NOTE 7)
60
50
40
30
20
10
0
0 50 100 150 200 250 300
FREQUENCY (MHz)
64008 TA01b
64008f
1