LTC6401-14 2GHz Low Noise, Low Distortion Differential ADC Driver for DC-140MHz FEATURESDESCRIPTION ■ 2GHz –3dB Bandwidth The LTC®6401-14 is a high-speed differential amplifi er ■ Fixed Gain of 5V/V (14dB) targeted at processing signals from DC to 140MHz. The ■ –91dBc IMD3 at 70MHz (Equivalent OIP3 = 49.3dBm) part has been specifi cally designed to drive 12-, 14- and ■ –81dBc IMD3 at 140MHz (Equivalent OIP3 = 44.5dBm) 16-bit ADCs with low noise and low distortion, but can also ■ 1.1nV/√⎯H⎯z Internal Op Amp Noise be used as a general-purpose broadband gain block. ■ 7.3dB Noise Figure The LTC6401-14 is easy to use, with minimal support ■ Differential Inputs and Outputs circuitry required. The output common mode voltage is ■ 200Ω Input Impedance set using an external pin, independent of the inputs, which ■ 2.85V to 3.5V Supply Voltage eliminates the need for transformers or AC-coupling ca- ■ 45mA Supply Current (135mW) pacitors in many applications. The gain is internally fi xed ■ 1V to 1.6V Output Common Mode, Adjustable at 14dB (5V/V). ■ DC- or AC-Coupled Operation ■ Max Differential Output Swing 4.6V The LTC6401-14 saves space and power compared to P-P ■ Small 16-Lead 3mm × 3mm × 0.75mm QFN Package alternative solutions using IF gain blocks and transform- ers. The LTC6401-14 is packaged in a compact 16-lead APPLICATIONS 3mm × 3mm QFN package and operates over the –40°C to 85°C temperature range. ■ Differential ADC Driver , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. ■ Differential Driver/Receiver All other trademarks are the property of their respective owners. ■ Single Ended to Differential Conversion ■ IF Sampling Receivers ■ SAW Filter Interfacing TYPICAL APPLICATION 3.3V 3.3V Equivalent Output IP3 vs Frequency 60 (NOTE 7) C2 C1 CF2 0.1μF 1000pF 33pF 50 C3 V+ RS1 RS3 0.1μF 15Ω 10Ω 40 VDD V AIN+ IN +IN +OUT R1 30 L1 C 68.5Ω C4 LTC6401-14 F1 LTC2208 0.1μF RS2 24nH 33pF RS4 15Ω 10Ω –IN 20 –OUT AIN– OUTPUT IP3 (dBm) V VCM R2 OCM CF3 29Ω COILCRAFT V– 33pF LTC2208 10 0603CS 130Msps 1.25V 16-Bit ADC 640114 TA01a 0 C5 R3 0 20 40 60 80 100 120 140 160 180 200 0.1μF 100Ω FREQUENCY (MHz) 640114 TA01b 640114f 1