Datasheet

ManualsBrandsTEXAS INSTRUMENTS ManualsLinear ICsLinear IC - Op-amp, differential amplifier Differential SOIC 8

INA145

Programmable Gain

DIFFERENCE AMPLIFIER

International Airport Industrial Park • Mailing Address: PO Box 11400, Tucson, AZ 85734 • Street Address: 6730 S. Tucson Blvd., Tucson, AZ 85706 • Tel: (520) 746-1111

Twx: 910-952-1111 • Internet: http://www.burr-brown.com/ • Cable: BBRCORP • Telex: 066-6491 • FAX: (520) 889-1510 • Immediate Product Info: (800) 548-6132

For most current data sheet and other product

information, visit www.burr-brown.com

DESCRIPTION

The INA145 is a precision, unity-gain difference

amplifier consisting of a precision op amp and on-

chip precision resistor network. Two external resistors

set the gain from 1V/V to 1000V/V. The input com-

mon-mode voltage range extends beyond the positive

and negative rails.

On-chip precision resistors are laser-trimmed to achieve

accurate gain and high common-mode rejection. Ex-

cellent TCR tracking of these resistors assures contin-

ued high precision over temperature.

The INA145 is available in the SO-8 surface-mount

package specified for the extended industrial tempera-

ture range, –40°C to +85°C.

FEATURES

● DIFFERENTIAL GAIN = 1V/V TO 1000V/V:

Set with External Resistors

● LOW QUIESCENT CURRENT: 570µA

● WIDE SUPPLY RANGE:

Single Supply: 4.5V to 36V

Dual Supplies: ±2.25V to ±18V

● HIGH COMMON-MODE VOLTAGE:

+8V at V

= +5V

±28V at V

= ±15V

● LOW GAIN ERROR: 0.01%

● HIGH CMR: 86dB

● SO-8 PACKAGE

APPLICATIONS

● CURRENT SHUNT MEASUREMENTS

● SENSOR AMPLIFIER

●

DIFFERENTIAL LINE RECEIVER

● BATTERY POWERED SYSTEMS

INA145

10kΩ

(1%)

INA145

40kΩ

RefV–

V+

G = 1

–

418

= (V

– V

)(1 + R

)

+–

SBOS120

Summary of content (15 pages)

PAGE 1
® INA145 INA 145 For most current data sheet and other product information, visit www.burr-brown.com Programmable Gain DIFFERENCE AMPLIFIER FEATURES DESCRIPTION ● DIFFERENTIAL GAIN = 1V/V TO 1000V/V: Set with External Resistors ● LOW QUIESCENT CURRENT: 570µA The INA145 is a precision, unity-gain difference amplifier consisting of a precision op amp and onchip precision resistor network. Two external resistors set the gain from 1V/V to 1000V/V.
PAGE 2
SPECIFICATIONS: VS = ±2.25V to ±18V Boldface limits apply over the specified temperature range, TA = –40°C to +85°C At TA = +25°C, G = 1, RL = 10kΩ connected to ground and ref pin connected to ground unless otherwise noted. INA145UA PARAMETER CONDITION OFFSET VOLTAGE, VO Input Offset Voltage vs Temperature vs Power Supply vs Time Offset Voltage, V01 INPUT VOLTAGE RANGE Common-Mode Voltage Range Common-Mode Rejection Over Temperature VOS ∆VOS /∆T PSRR MIN RTI(1, 2) VCM = VO = 0V VS = ±1.
PAGE 3
SPECIFICATIONS: VS = +5V Single Supply Boldface limits apply over the specified temperature range, TA = –40°C to +85°C At TA = +25°C, G = 1, RL = 10kΩ connected to ground and ref pin connected to 2.5V unless otherwise noted.
PAGE 4
AMPLIFIER A1, A2 PERFORMANCE Boldface limits apply over the specified temperature range, TA = –40°C to +85°C At TA = +25°C, G = 1, RL = 10kΩ connected to ground and ref pin connected to ground unless otherwise noted. INA145UA PARAMETER CONDITION MIN TYP MAX UNITS RTI(1, 2) OFFSET VOLTAGE, VO Input Offset Voltage vs Temperature VOS ∆VOS /∆T VS = ±15V, VCM = VO = 0V ±0.
PAGE 5
TYPICAL PERFORMANCE CURVES At TA = +25°C, VS = ±15V, G = 1, RL = 10kΩ connected to ground and Ref pin connected to ground, unless otherwise noted.
PAGE 6
TYPICAL PERFORMANCE CURVES (Cont.) At TA = +25°C, VS = ±15V, G = 1, RL = 10kΩ connected to ground and Ref pin connected to ground, unless otherwise noted. QUIESCENT CURRENT AND SHORT-CIRCUIT CURRENT vs TEMPERATURE SLEW RATE vs TEMPERATURE 18 0.55 630 16 610 14 590 12 570 10 IQ 550 8 G=1 0.5 0.45 0.4 0.35 530 6 510 4 490 2 0.25 0 0.2 470 –60 –40 –20 20 0 40 60 0.
PAGE 7
TYPICAL PERFORMANCE CURVES (Cont.) At TA = +25°C, VS = ±15V, G = 1, RL = 10kΩ connected to ground and Ref pin connected to ground, unless otherwise noted. OFFSET VOLTAGE DRIFT PRODUCTION DISTRIBUTION OFFSET VOLTAGE PRODUCTION DISTRIBUTION 20 VS = ±15V VS = ±15V Relative Frequency Relative Frequency Typical Production Distribution of Packaged Devices 15 10 5 –10 –9 –8 –7 –6 –5 –4 –3 –2 –1 0 1 2 3 4 5 6 7 8 9 10 1 0.8 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 –0.
PAGE 8
APPLICATION INFORMATION SETTING THE GAIN The gain of the INA145 is set by using two external resistors, RG1 and RG2, according to the equation: The INA145 is a programmable gain difference amplifier consisting of a gain of 1 difference amplifier and a programmable-gain output buffer stage. Basic circuit connections are shown in Figure 1. Power supply bypass capacitors should be connected close to pins 4 and 7, as shown.
PAGE 9
OFFSET TRIM INPUT IMPEDANCE The INA145 is laser-trimmed for low offset voltage and drift. Most applications require no external offset adjustment. Figure 2 shows an optional circuit for trimming the offset voltage. A voltage applied to the Ref terminal will be summed with the output signal. This can be used to null offset voltage.
PAGE 10
kΩ Pole at 106Hz G=1 1500pF 5 RG2 1MΩ RG1 10kΩ 2 – VIN 6 5 – VIN VO 2 10kΩ 6 3 + VIN VO INA145 1 + VIN 8 R4 3 INA145 1 G= R3 R3 R3 + R4 8 G≤1 22nF Pole at 720Hz FIGURE 5. Creating Gains Less Than Unity. FIGURE 4. Noise Filtering. RG2 10kΩ 5 2 – VIN R1 R2 0V ≤ VO ≤ 5V 10kΩ 6 VO Alternate Soft Clamp To Pin 8 3 + VIN R3 R4 INA145 1 8 1N914 1N4684 (3.3V) 1N914 Voltage Reference (1) 5.
PAGE 11
RG2 100kΩ RG1 11kΩ Power Supply 5 2 For sense resistors (RS) greater than 5Ω, use series compensation resistor (RC) for good common-mode rejection. Sense resistors greater than 200Ω are not recommended. G = 10 RC 10Ω VO 6 RS 10Ω 3 INA145 1 Load 8 VO1 FIGURE 7. Current Monitor, G = 1. +5V 24V 8.4kΩ Feedback 7 5 2 8kΩ 1V 6 SHUNT R-I Lamp/10 e.g., 0.1Ω for 1A VO 10kΩ 1V – 50mV 3 2kΩ INA145 4 1 8 10MΩ Lamp FIGURE 8.
PAGE 12
PACKAGE OPTION ADDENDUM www.ti.
PAGE 13
PACKAGE MATERIALS INFORMATION www.ti.com 11-Mar-2008 TAPE AND REEL INFORMATION *All dimensions are nominal Device INA145UA/2K5 Package Package Pins Type Drawing SOIC D 8 SPQ Reel Reel Diameter Width (mm) W1 (mm) 2500 330.0 12.4 Pack Materials-Page 1 A0 (mm) B0 (mm) K0 (mm) P1 (mm) 6.4 5.2 2.1 8.0 W Pin1 (mm) Quadrant 12.
PAGE 14
PACKAGE MATERIALS INFORMATION www.ti.com 11-Mar-2008 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) INA145UA/2K5 SOIC D 8 2500 346.0 346.0 29.
PAGE 15
IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements, and other changes to its products and services at any time and to discontinue any product or service without notice. Customers should obtain the latest relevant information before placing orders and should verify that such information is current and complete.