ANALOG DEVICES ADA4500-2 Service Manual

8.7MHz, 15nV/√Hz, Rail-to-Rail I/O,

Zero Input Crossover Distortion Amplifiers

Preliminary Technical Data

FEATURES

PSRR: 100dB minimum
CMRR: 100 dB minimum
Supply current: 1.6 mA/amp max
Wide Bandwidth: 8.7 MHz

2.7 V to 5.5 V single-supply operation
Rail-to-rail input and output
Low noise

1.1 µV p-p from 0.1 Hz to 10 Hz

15nV/√Hz @ 1kHz
150 V offset voltage maximum
Very low input bias current: 10 pA maximum

APPLICATIONS

Pressure and position sensors
Remote security
Medical monitors
Process control
Hazard detectors
Photo Diode applications

GENERAL DESCRIPTION

The ADA4500 is a dual 8.7MHz, 15 nV/√Hz, low power amplifier
featuring rail-to-rail input and output swings while operating from a 2.7
V to 5.5 V single power supply.

Employing a novel circuit technology, these amplifiers offer zero input
crossover distortion (high linearity and excellent PSRR and CMRR
performance), precision, wide bandwidth and very low bias current.
This technology offer the excellent CMRR over the supply range without
the cross-over distortion seen with the traditional complementary input
stage.

This combination of these features makes the ADA4500 amplifier an
ideal choice for precision sensor applications as it minimizes errors due
to power supply voltage variations over the supply voltage and maintains
high CMRR even for a rail-to-rail input op amp. This results in excellent
performance for driving Analog-to-Digital (A/D) converters without
degradation of performance. The input common mode range includes
both the negative and positive supplies.

Sensors, handheld instrumentation, precision signal conditioning, and
patient monitors can benefit from the features of the ADA4500.

The ADA4500 is specified for the extended industrial temperature range
(−40°C to +125°C). ADA4500-2 dual amplifiers are available in the
standard 8-lead MSOP and LFCSP.

ADA4500-2

PIN CONFIGURATIONS

ADA4500-2

Figure 1. 8-Lead MSOP& LFCSP
(RM & CP Suffix)

Rev. PrA

Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] www.analog.com
Fax: [phone] ©2012 Analog Devices, Inc. All rights reserved.

Preliminary Technical Data

ADA4500-2

SPECIFICATIONS

ELECTRICAL CHARACTERISTICS; VS = 2.7V

VS = 2.7 V, VCM = Vs/2, TA = 25°C, RL = 10kΩ, CL = 30 pF, unless otherwise specified.

Table 1.

Parameter Symbol Conditions Min Typ Max Unit

INPUT CHARACTERISTICS

Offset Voltage VOS 0 V < VCM < 2.7 V 150 V
Input Bias Current IB 1 10 pA

−40°C < TA < +125°C 600 pA
Input Offset Current IOS 0.5 1 pA

−40°C < TA < +125°C 100 pA
Input Voltage Range −40°C < TA < +125°C (V-) -0.3 (V+) + 0.3 V
Common-Mode Rejection Ratio CMRR VCM = V- to V+ 100 110 dB

−40°C < TA < +125°C 100 dB
Large Signal Voltage Gain AVO (V-) + 0.05 < V

−40°C < TA < +125°C 105 dB
Offset Voltage Drift

V

OS

/T

−40°C < T

Input Capacitance

Common-Mode Input Capacitance 3 pF
Differential Input Capacitance 2 pF

Input Impedance TBD
OUTPUT CHARACTERISTICS

Output Voltage High VOH R
R
Output Voltage Low VOL R
R

= 10 kΩ to GND 2.95 2.97 V

L

= 2 kΩ to GND 2.90 2.95 V

L

= 10 kΩ to VS 10 50 mV

L

= 2 kΩ to VS 25 100 mV

L

Short Circuit Limit ISC +20/-40 mA

POWER SUPPLY

Power Supply Rejection Ratio PSRR VS = 2.7 V to 5.5 V 100 110 dB

−40°C to +125°C 100 dB
Supply Current/Amplifier ISY V

= VS /2 1.35 1.6 mA

O

−40°C < TA < +125°C 1.9 mA

DYNAMIC PERFORMANCE

Slew Rate SR 4.7 V/µs
Gain Bandwidth Product GBP 8.6 MHz
Phase Margin

ФM

55 Degrees

NOISE PERFORMANCE

Total Harmonic Distortion + Noise THD+N VS = 2.7 V, G= +1,

f = 20Hz to 20kHz

Peak-to-Peak Noise e

f = 0.1 to 10 Hz 1.1 µV p-p

n p-p

Voltage Noise Density en f = 1 kHz 15 nV/√Hz
Current Noise Density in f = 1 kHz 0.5 fA/√Hz

Rev. PrA

Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.

< (V+) - 0.05 110 130 dB

OUT

< +125°C 0.2 5 µV/°C

A

MΩ

0.002 %

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] www.analog.com
Fax: [phone] ©2009 Analog Devices, Inc. All rights reserved.