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LTC1750

1750f

14-Bit, 80Msps

Wide Bandwidth ADC

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Sample Rate: 80Msps

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500MHz Full Power Bandwidth S/H

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Direct IF Sampling Up to 500MHz

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75.5dB SNR and 90dB SFDR (PGA = 0)

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73dB SNR and 90dB SFDR (PGA = 1)

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No Missing Codes

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Single 5V Supply

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Power Dissipation: 1.45W

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Two Pin Selectable Reference Values

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Two’s Complement or Offset Binary Outputs

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Out-of-Range Indicator

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Data Ready Output Clock

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Pin-for-Pin Family

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48-Pin TSSOP Package

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Telecommunications

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Receivers

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Cellular Base Stations

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Spectrum Analysis

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Imaging Systems

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MRI

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Tomography

, LTC and LT are registered trademarks of Linear Technology Corporation.

The LTC

signed for digitizing wide dynamic range signals up to

frequencies of 500MHz. The input range of the ADC can be

optimized with the on-chip PGA sample-and-hold circuit

and flexible reference circuitry.

The LTC1750 has a highly linear sample-and-hold circuit

with a bandwidth of 500MHz. The SFDR is 82dB with an

allows undersampling of IF frequencies with minimal

degradation in SNR. DC specs include

±3LSB INL and no

missing codes.

The digital interface is compatible with 5V, 3V, 2V and

LVDS logic systems. The ENC and ENC inputs may be

driven differentially from PECL, GTL and other low swing

logic families or from single-ended TTL or CMOS. The low

noise, high gain ENC and ENC inputs may also be driven

by a sinusoidal signal without degrading performance. A

separate output power supply can be operated from 0.5V

to 5V, making it easy to connect directly to any low voltage

DSPs or FIFOs.

The 48-pin TSSOP package with a flow-through pinout

simplifies the board layout.

80Msps, 14-Bit ADC with a 2.25V Differential Input Range

DESCRIPTIO

FEATURES

APPLICATIO S

BLOCK DIAGRA

OF

14-BIT

PIPELINED ADC

14

S/H

CIRCUIT

±1.125V

DIFFERENTIAL

ANALOG INPUT

+

PGA

–

SENSE

4.7

µF

DIFF AMP

REFLA

REFHB

GND

1750 BD

ENC

4.7

µF

1

µF1µF

0.1

µF

0.1

µF

REFHA

REFLB

BUFFER

RANGE

SELECT

CORRECTION

LOGIC AND

SHIFT

REGISTER

OUTPUT

LATCHES

CONTROL LOGIC

OGND

0.5V TO 5V

5V

0.1

µF

1

µF

1

µF

1

µF

D13

D0

CLKOUT

•

•

•

ENC

DIFFERENTIAL

ENCODE INPUT

MSBINV

0.1

µF