8-Bit, 250 MSPS

3.3 V A/D Converter

AD9481

Rev. 0

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FEATURES

DNL = ±0.35 LSB

INL = ±0.26 LSB

Single 3.3 V supply operation (3.0 V to 3.6 V)

Power dissipation of 439 mW at 250 MSPS

1 V p-p analog input range

Internal 1.0 V reference

Single-ended or differential analog inputs

De-multiplexed CMOS outputs

Power-down mode

Clock duty cycle stabilizer

APPLICATIONS

Digital oscilloscopes

Instrumentation and measurement

Communications

Point-to-point radios

Digital predistortion loops

FUNCTIONAL BLOCK DIAGRAM

D7A TO D0A

VIN+

VIN–

CLK+

CLK–

VREF SENSE

DCO+

DCO–

AGND DRGND

DRVDD

AVDD

AD9481

PDWN

S1

CLOCK

MGMT

T AND H

8-BIT

ADC

PIPELINE

CORE

LOGIC

REFERENCE

PORT

A

8

PORT

B

8

8

DS+

DS–

D7B TO D0B

Figure 1.

GENERAL DESCRIPTION

The AD9481 is an 8-bit, monolithic analog-to-digital converter

(ADC) optimized for high speed and low power consumption.

Small in size and easy to use, the product operates at a

250 MSPS conversion rate, with excellent linearity and dynamic

performance over its full operating range.

To minimize system cost and power dissipation, the AD9481

includes an internal reference and track-and-hold circuit. The

user only provides a 3.3 V power supply and a differential

encode clock. No external reference or driver components are

required for many applications.

The digital outputs are TTL/CMOS-compatible with an option

of twos complement or binary output format. The output data

bits are provided in an interleaved fashion along with output

clocks that simplifies data capture.

The AD9481 is available in a Pb-free, 44-lead, surface-mount

package (TQFP-44) specified over the industrial temperature

range (−40°C to +85°C).

PRODUCT HIGHLIGHTS

1. Superior linearity. A DNL of ±0.35 makes the AD9481

suitable for many instrumentation and measurement

applications

2. Power-down mode. A power-down function may be exercised

to bring total consumption down to 15 mW.

3. De-multiplexed CMOS outputs allow for easy interfacing

with low cost FPGAs and standard logic.