Analog Devices AD604 AD604

AD604

Rev. E | Page 23 of 32

AD604

+5V

–5V

IN1

VREF

OUT1

VOCM

VG1

VG2

OUT2

NOTE2

NOTE3

IN2

PAO2

PAO1

–DSX1

+DSX1

PAI1

FBK1

PAO1

COM1

COM2

PAI2

FBK2

PAO2

+DSX2

–DSX2

VGN1

VREF

VPOS

GND1

OUT1

VNEG

VPOS

GND2

OUT2

VOCM

VGN2

OPTIONAL

RGN

0.1µF

RGN

0.1µF

5pF

500Ω

0.1µF

C12

0.1µF

C11

0.1µF

C10

0.1µF

5pF R4

500Ω

0.1µF

NOTES

1.PAO1 AND PAO2 ARE US ED TO MEASURE PREAMPS.

2.RGN = 0 NOMINALLY;PREAMP GAIN = 5, RGN = OPEN;PREAMP GAIN = 10.

3.WHEN M INSERIES.

0540-052

EASURINGBW W ITH 50ΩSPECTRUM ANALYZER,USE 450Ω

Figure 53. Basic Test Board

PAI

OUT R A

HP3577B

450Ω

50Ω

HP11636B

POWER

SPLITTER

0.1µF

49.9Ω

AD604

DUT

00540-053

Figure 54. Setup for Gain Measurements

Contents

Main Dual, Ultralow Noise Variable Gain Amplifier FEATURES APPLICATIONS FUNCTIONAL BLOCK DIAGRAM GENERAL DESCRIPTION AD604 TABLE OF CONTENTS AD604 SPECIFICATIONS AD604 AD604 ABSOLUTE MAXIMUM RATINGS ESD CAUTION AD604 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 3. Pin Function Descriptions AD604 Figure 8. Gain Error vs. VGN at Different Frequencies Figure 5. Gain vs. VGN for Different Gain Scalings GAIN SCALING (dB/V) Figure 9. Gain Error vs. VGN for Two Gain Scaling Values Figure 14. Output Referred Noise vs. VGN for Three Temperatures Figure 11. Gain Match; VGN1 = VGN2 = 2.50 V PERCENTAGE Figure 15. Input Referred Noise vs. VGN Figure 20. Noise Figure vs. VGN 00.40.81.21.62.02.42.8 0 2 Rev. E | Page 10 of 3 Figure 21. Harmonic Distortion vs. Frequency Figure 26. Third-Order Intercept vs. VGN 100ns/DIV Figure 32. DSX Common-Mode Rejection Ratio vs. Frequency CROSSTALK (dB) 100ns/DIV INPUT IMPEDANCE () DELAY (ns) Figure 34. Input Bias Current vs. Temperature SUPPLY CURRENT (mA) AD604 THEORY OF OPERATION PREAMPLIFIER () () [] () DIFFERENTIAL LADDER (ATTENUATOR) AC COUPLING GAIN CONTROL INTERFACE ACTIVE FEEDBACK AMPLIFIER (FIXED-GAIN AMP) Page AD604 APPLICATIONS INFORMATION ULTRALOW NOISE AGC AMPLIFIER WITH 82 dB TO 96 dB GAIN RANGE Page Rev. E | Page 21 of 3 500mV 100 90 80 70 60 50 40 30 20 10 0 10 ULTRALOW NOISE, DIFFERENTIAL INPUT- DIFFERENTIAL OUTPUT VGA the signal amplitude compared with when they are driven single-ended. AD604 Figure 50. Ultralow Noise, Differential Input-Differential Output VGA 20ns20mV MEDICAL ULTRASOUND TGC DRIVING THE AD9050, A 10-BIT, 40 MSPS ADC AD604 AD9050 AD7226 AD9631 AD604 Figure 53. Basic Test Board AD604 Figure 54. Setup for Gain Measurements AD604 EVALUATION BOARD DSX INPUT CONNECTIONS Differential DSX Inputs USING THE PREAMPLIFIER PREAMPLIFIER GAIN OUTPUTS DC OPERATING CONDITIONS EVALUATION BOARD ARTWORK AND SCHEMATIC AD604 Figure 61. Evaluation Board Schematic Table 6. Bill of Materials 40 MHz dual low noise VGA AD604 OUTLINE DIMENSIONS ORDERING GUIDE