LT6604-2.5

1

660425f

TYPICAL APPLICATION

FEATURES

APPLICATIONS

DESCRIPTION

Dual Very Low Noise,

Differential Amplifier and

2.5MHz Lowpass Filter

amplifiers, each with a 4th order, 2.5MHz lowpass filter. The

fixed frequency lowpass filter approximates a Chebyshev

response. By integrating a filter and a differential ampli-

fier, distortion and noise are made exceptionally low. At

unity gain, the measured in-band signal-to-noise ratio is

an impressive 86dB. At higher gains, the input referred

noise decreases, allowing the part to process smaller

input differential signals without significantly degrading

the signal-to-noise ratio.

Gain and phase are well matched between the two chan-

nels. Gain for each channel is independently programmed

using two external resistors. The LT6604-2.5 enables level

shifting by providing an adjustable output common mode

voltage, making it ideal for directly interfacing to ADCs.

The LT6604-2.5 is fully specified for 3V operation. The

differential design enables outstanding performance up

See the back page of this datasheet for a complete list of

related single and dual differential amplifiers with integrated

2.5MHz to 20MHz lowpass filters.

L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other

trademarks are the property of their respective owners.v

4th Order Filters

Approximates Chebyshev Response

Guaranteed Phase and Gain Matching

Resistor-Programmable Differential Gain

HD2: 92dBc

HD3: 88dBc

× 7mm × 0.75mm QFN Package

Wireless Infrastructure or Networking Applications

Channel to Channel Gain Matching

GAIN MATCH (dB)

18

16

14

12

10

8

6

4

2

660425 TA01b

0

50 TYPICAL UNITS

GAIN = 1

–0.25

0.05

–0.05

0.15

–0.15

0.25

0

1580Ω

50Ω

50Ω

1580Ω

3V

3V

+

–

+

–

660425 TA01

+

–

DOUT

DUAL ADC

AIN

LT6604-2.5

LTC22xx

+

–

1580Ω

1580Ω

3V

–OUTA

+OUTA

–OUTB

+OUTB

+INA

+INB

–INA

–INB

+

–

+

–

+

–

DOUT

AIN

+

–

50Ω

50Ω

18pF

0.01μF

0.01μF

18pF