Datasheet LT6600-15 (Analog Devices)

LT6600-15 Very Low Noise, Differential Amplifi er and 15MHz Lowpass Filter
FEATURES DESCRIPTION
n Programmable Differential Gain via Two External The LT®6600-15 combines a fully differential amplifi er with a Resistors 4th order 15MHz lowpass fi lter approximating a Chebyshev n Adjustable Output Common Mode Voltage frequency response. Most differential amplifi ers require n Operates and Specifi ed with 3V, 5V, ±5V Supplies many precision external components to tailor gain and n 0.5dB Ripple 4th Order Lowpass Filter with 15MHz bandwidth. In contrast, with the LT6600-15, two external Cutoff resistors program differential gain, and the fi lter’s 15MHz n 76dB S/N with 3V Supply and 2V cutoff frequency and passband ripple are internally set. P-P Output n Low Distortion, 2V The LT6600-15 also provides the necessary level shifting P-P, 800Ω Load, VS = 3V 1MHz: 86dBc 2nd, 90dBc 3rd to set its output common mode voltage to accommodate 10MHz: 63dBc 2nd, 69dBc 3rd the reference voltage requirements of A/Ds. n Fully Differential Inputs and Outputs Using a proprietary internal architecture, the LT6600-15 n Compatible with Popular Differential Amplifi er integrates an antialiasing fi lter and a differential amplifi er/ Pinouts driver without compromising distortion or low noise perfor- n SO-8 Package mance. At unity gain the measured in band signal-to-noise ratio is an impressive 76dB. At higher gains the input referred noise decreases so the part can process smaller
APPLICATIONS
input differential signals without signifi cantly degrading n High Speed ADC Antialiasing and DAC Smoothing in the output signal-to-noise ratio. Networking or Cellular Base Station Applications The LT6600-15 also features low voltage operation. The n High Speed Test and Measurement Equipment differential design provides outstanding performance for n Medical Imaging a 2VP-P signal level while the part operates with a single n Drop-In Replacement for Differential Amplifi ers 3V supply. L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. The LT6600-15 is packaged in an SO-8 and is pin compat- ible with standalone differential amplifi ers.
TYPICAL APPLICATION An 8192 Point FFT Spectrum
0 LT6600-15 LTC2249 INPUT 10.7MHz –10 3V 2VP-P –20 0.1μF fSAMPLE = 80MHz 3V –30 RIN 5.6pF –40 536Ω 3 1 25Ω – V+ 4 –50 7 + + V –60 MID 5.6pF A 2 IN DOUT –70 0.01μF 25Ω VOCM 8 – – AMPLITUDE (dB) –80 V 5 IN + 5.6pF V R CM V– IN 6 –90 536Ω –100 2.2μF –110 GAIN = 536Ω/RIN 660015 TA01a –120 0 10 20 30 40 FREQUENCY (MHz) 660015 TA01b 660015fb 1