Circuit Note

CN-0140

Circuit Designs Using Analog Devices Products

Apply these product pairings quickly and with confidence.

For more information and/or support call 1-800-AnalogD

(1-800-262-5643) or visit www.analog.com/circuit.

Devices Connected/Referenced

ADL5356

1.2 GHz to 2.5 GHz, Dual-Balanced Mixer,

LO Buffer, IF Amplifier, and RF Balun

AD8376

Ultralow Distortion IF Dual VGA

AD9258

14-Bit, 125 MSPS, 1.8 V Dual ADC

AD9517-4

12-Output Clock Generator with

Integrated 1.6 GHz VCO

High Performance, Dual Channel IF Sampling Receiver

Rev. 0

“Circuits from the Lab” from Analog Devices have been designed and built by Analog Devices

engineers. Standard engineering practices have been employed in the design and construction of

eachcircuit,andtheirfunctionandperformance havebeentestedandverifiedinalabenvironment

atroomtemperature.However,youaresolelyresponsible fortestingthe circuit anddetermining its

suitability and applicability for your use and application. Accordingly, in no event shall Analog

Devices be liable for direct, indirect, special, incidental, consequential or punitive damages due to

anycausewhatsoeverconnectedtotheuseofany“CircuitfromtheLab”. (Continuedonlastpage)

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.

Tel: 781.329.4700

www.analog.com

Fax: 781.461.3113

©2010 Analog Devices, Inc. All rights reserved.

CIRCUIT FUNCTION AND BENEFITS

This circuit is a high performance, dual channel IF sampling

receiver, also called a “main” and “diversity” receiver in

base station terminology. The downconverting receiver uses

a single IF frequency of 153.6 MHz and includes a dual

downconverting mixer, digitally controlled dual VGA, dual

ADC, and clock synthesizer. The circuit takes an incoming

RF waveform and outputs a dual 14-bit resolution digital data

stream. It is optimized for high frequency IF sampling and

provides exceptional spurious-free dynamic range (SFDR)

performance of 79.61 dBc with a sampling rate of 122.88 MSPS

at the high gain setting.

CIRCUIT DESCRIPTION

This circuit includes the RF front end, as well as the IF sampling

receiver. It is composed of a dual balanced mixer, broadband IF

SAW filter, digitally controlled dual VGA, and dual ADC. The

circuit also includes a synthesizer, which generates the ADC

sampling clock.

The ADL5356 dual balanced mixer is designed to downconvert

radio frequencies (RF) primarily between 1200 MHz and

2500 MHz to lower intermediate frequencies (IF) between

30 MHz and 450 MHz.

5

18pF

18pF

18pF

5V

5V

5V

18pF

58nH

72nH

470pF

470pF

0.1µF

0.1µF

57.6

Ω

470pF

100pF

1.5k

Ω

430

Ω

200

Ω

200

Ω

10nF

50

Ω

0.1µF

0.1µF

0.1µF

0.22µF

REFIN

OUT0

CP

BYPASS

LF

1/2

AD8376

309

Ω 3.3pF

A0 TO

A4

20pF

1µH

1µH

330nH

330nH

330nH

330nH

CML

165

Ω

165

Ω

CML CLK+

122.88MHz

CLK–

56nH

33

Ω

33

Ω

1/2

AD9258

5V

1.21k

Ω

GM

IN

CT

ON

OP

LG

330nH

330nH

390

Ω

50

Ω

LO IN

1796.4MHz

REF IN

30.72MHz

5V

5V

LOSW

LOI2

22pF

22pF

50

Ω

10nF

10pF

RF IN

1950MHz

1/2

ADL5356

153.6MHz

BW = 20MHz

EPCOS

B5206

SAW FILTER

1.8V

AVDD

3V

1.8V

DVDD

14

1:1

AD9517-4

REFIN

OUT0

NOTES

1. ALL PINS AND CONNECTIONS TO ADL5356, AD8376, AD9258 AND AD9417 NOT SHOWN.

CONSULT PRODUCT DATA SHEETS FOR DETAILED INFORMATION.

Figure 1. Broadband Dual Channel IF Sampling Receiver (Simplified Schematic: Only One-Half of the Receiver Is Shown. All Connections and Decoupling Not Shown)