The AD927x family of octal receivers addresses the challenges facing designers of next-generation, high performance, and portable ultrasound systems, including the need to balance image quality and diagnostic capabilities with power requirements. The AD927x integrates a complete 8-channel (octal) ultrasound receiver on a single chip replacing previous discrete solutions. Each of the eight channels on the chip includes a low noise preamplifier (LNA), variable gain amplifier (VGA), antialiasing filter (AAF), and 12-bit analog-to-digital converter (ADC). Each channel is optimized for dynamic performance and low power in applications where a small package size is critical.

Product HighlightsLow Noise: The input-referred noise is dependent on the specific model selected. The AD9272 offers an LNA input-referred noise of 0.75 nV/√Hz and a combined input-referred noise of the entire channel of 0.83 nV/√Hz at maximum gain—giving the AD9272 a 6 dB dynamic range advantage over competing parts.

Low Power: The power dissipation is dependent on the specific model selected. The AD9273 offers 100 mW per channel at 12 bits/40 MSPS and 50 mW per channel in CW Doppler mode.

Input Options: The AD927x boasts the largest linear input range up to 0.733 V p-p including several input options and active termination. With active termination, the user can design in several different probe types and maintain the dynamic range of the system.

A Range of Sample Conversion Rates: The sample conversion rate is dependent on the specific model selected. The AD9272 12-bit ADC has a conversion rate of 10 MSPS to 80 MSPS. The AD9271/AD9273 12-bit ADC has a conversion rate of 10 MSPS to 50 MSPS.

Digital Interface: Digital LVDS outputs support both IEEE and ANSI standards. Double termination allows the user to make longer trace runs supporting digital receivers off board. A data clock output (DCO±) operates up to 480 MHz and supports double data rate (DDR) operation.

User Flexibility: Serial port interface (SPI) allows designers to further customize the noise, gain, and bias for any given imaging mode, probe, or power requirement.By changing SPI registers, designers can optimize an ultrasound signal processing architecture for the best possible noise performance or longest battery life. An easy to use software tool simplifies each configuration.

Small Form Factor: Eight channels of full TGC path, ADC, and crosspoint switch contained within an RoHS compliant, 100-lead, 16 mm × 16 mm TQFP.

Octal Receivers

Part NumberLNA Input Range

(mV p-p)LNA Input Noise

(nV/√Hz)Total Channel Input Noise, No

Termination, RS = 0 𝛀 (nV/√Hz)

Input Dynamic Range for Channel, with Termination, RS = RIN = 200 𝛀

(dB/√Hz)

Power @ 40 MSPS (mW)

AD9271 400, 333, 250 1.4, 1.2, 1.1; 1 pA 1.65, 1.44, 1.31 158.5, 157.9, 156.4 150AD9272 733, 550, 367 0.98, 0.86, 0.75; 1 pA 1.21, 1.01, 0.83 165.4, 163.8, 161.2 191AD9273 733, 550, 367 1.60, 1.42, 1.26; 1 pA 1.92, 1.63, 1.37 163.2, 162.0, 159.8 104

AD927x Family of Octal Receivers High Performance and Portable Ultrasound

SE

RIA

LP

OR

TIN

TE

RFA

CE

REFERENCE

FCO+

FCO–DCO+DCO–

LNA

LO-H

LOSW-H

LI-HLG-H

12-BITADC

SERIALLVDS

DOUTH+DOUTH–

LNA

LO-G

LOSW-G

LI-GLG-G

12-BITADC

SERIALLVDS

DOUTG+DOUTG–

LNA

LO-F

LOSW-F

LI-FLG-F

12-BITADC

SERIALLVDS

DOUTF+DOUTF–

LNA

LO-E

LOSW-E

LI-ELG-E

12-BITADC

SERIALLVDS

DOUTE+DOUTE–

LNA

LO-D

LOSW-D

LI-DLG-D

12-BITADC

SERIALLVDS

DOUTD+DOUTD–

LNA

LO-C

LOSW-C

LI-CLG-C

12-BITADC

SERIALLVDS

DOUTC+DOUTC–

LNA

LO-B

LOSW-B

LI-BLG-B

12-BITADC

SERIALLVDS

DOUTB+DOUTB–

LNA

LO-A

LOSW-A

LI-ALG-A

12-BITADC

SERIALLVDS

DOUTA+DOUTA–

AV

DD

1

AV

DD

2

ST

BY

DR

VD

D

PD

WN

CLK

–C

LK+

SD

IO

SC

LKC

SB

RB

IAS

VR

EF

GA

IN+

GA

IN–

CW

D[7

:0]

CW

VD

D

SWITCHARRAY

DA

TA

RA

TE

MU

LTIP

LIE

R

AAF

AAF

AAF

AAF

AAF

AAF

AAF

AAF

AD9272/AD9273

VGA

VGA

VGA

VGA

VGA

VGA

VGA

VGA

AD9272/AD9273 functional block diagram.

www.analog.com/medicalics

RS

NF

(dB

)

10

8

9

7

5

4

6

3

2

1

010 100 1000

UNTERMINATED

RIN = 200 (ACTIVE TERMINATED)

The serial port interface (SPI) control offers a wide range of flexible features to meet specific system requirements.

©2008 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners.Printed in the U.S.A. PH07749-1-10/08 www.analog.com/medicalics

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CW (ANALOG)BEAMFORMER

AUDIOOUTPUT

DISPLAY

IMAGE AND MOTION PROCESSING

(B MODE)

COLOR DOPPLER (PW) PROCESSING

(F MODE)

SPECTRAL DOPPLERPROCESSING MODE

AAFVGA

T/R SWITCHESHV MUX/DEMUX

MULTICHANNELS

Tx HV AMPS

Rx BEAMFORMER(B AND F MODES)

Tx BEAMFORMER BEAMFORMERCENTRAL CONTROL

AD9271/AD9272/AD9273

CW

LNA ADC

BIDIRECTIONAL CABLE

TRANSDUCER ARRAY128, 256, ETC.,

ELEMENTS

The AD9272 and AD9273 offer the system designer active termination for input impedance matching. This results in a superior noise figure for the system. AD9272 noise figure performance has a 3 dB advantage over the competition when RS = RIN = 200 Ω.