1. Products
  2. Amplifiers
  3. Operational Amplifiers (Op Amps)
  4. Low Power Op Amps (≤ 1mA/amp)
  5. LT1638


Overview

Features and Benefits

  • Operates with Inputs Above V+
  • Rail-to-Rail Input and Output
  • Low Power: 230μA per Amplifier Max
  • Gain Bandwidth Product: 1.2MHz
  • Slew Rate: 0.4V/μs
  • High Output Current: 25mA Min
  • Specified on 3V, 5V and ±15V Supplies
  • Reverse Battery Protection to 18V
  • No Supply Sequencing Problems
  • High Voltage Gain: 1500V/mV
  • Single Supply Input Range: –0.4V to 44V
  • High CMRR: 98dB
  • No Phase Reversal
  • Available in 14-Lead SO, 8-Lead MSOP and DFN Packages

Product Details

The LT1638 is a low power dual rail-to-rail input and output operational amplifier available in the standard 8-pin PDIP and SO packages as well as the 8-lead MSOP package. The LT1639 is a low power quad rail-to-rail input and output operational amplifier offered in the standard 14-pin PDIP and surface mount packages. For space limited applications the LT1638 is available in a 3mm × 3mm × 0.8mm dual fine pitch leadless package (DFN).

The LT1638/LT1639 op amps operate on all single and split supplies with a total voltage of 2.5V to 44V drawing only 170μA of quiescent current per amplifier. These amplifiers are reverse battery protected and draw no current for reverse supply up to 18V.

The input range of the LT1638/LT1639 includes both supplies, and a unique feature of this device is its capability to operate over the top with either or both of its inputs above V+. The inputs handle 44V, both differential and common mode, independent of supply voltage. The input stage incorporates phase reversal protection to prevent false outputs from occurring when the inputs are below the negative supply. Protective resistors are included in the input leads so that current does not become excessive when the inputs are forced below the negative supply. The LT1638/LT1639 can drive loads up to 25mA and still maintain rail-to-rail capability. The op amps are unity-gain stable and drive all capacitive loads up to 1000pF when optional output compensation is used.

Applications

  • Battery- or Solar-Powered Systems
    • Portable Instrumentation
    • Sensor Conditioning
  • Supply Current Sensing
  • Battery Monitoring
  • Micropower Active Filters
  • 4mA to 20mA Transmitters

Product Lifecycle icon-recommended Production

At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.

Evaluation Kits (1)

Tools & Simulations

LTspice

LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.

LTspice

Models for the following parts are available in LTspice:

LT1638

Design Tools

Analog Filter Wizard

Use the Analog Filter Wizard to design low-pass, high-pass, or band-pass filters with actual op amps in minutes. As you progress through the design process, you can observe the characteristics of your filter design from ideal specifications to real world circuit behavior. Quickly evaluate the tradeoffs in op amp specifications - including gain-bandwidth, noise, and supply current – to determine the best filter design for your requirements.

Analog Photodiode Wizard

Use Photodiode Wizard to design a transimpedance amplifier circuit to interface with a photodiode. Select a photodiode from the library included in the tool, or enter custom photodiode specifications. Quickly observe tradeoffs between Bandwidth, Peaking (Q), and ENOB/SNR. Modify circuit parameters, and immediately see results in plots for pulse response, frequency response, and noise gain.

Product Recommendations

LT1638 Companion Parts

Recommended Related Parts

Design Resources

ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well.  "Zero defects" for shipped products is always our goal.View our quality and reliability program and certifications for more information.

Part Number Material Declaration Reliability Data Pin/Package Drawing CAD Symbols, Footprints & 3D Models
LT1638CDD#PBF Material Declaration Reliability Data 8-Lead DFN (3mm x 3mm x 0.75mm w/ EP)
LT1638CDD#TRPBF Material Declaration Reliability Data 8-Lead DFN (3mm x 3mm x 0.75mm w/ EP)
LT1638CMS8#PBF Material Declaration Reliability Data 8-Lead MSOP
LT1638CMS8#TRPBF Material Declaration Reliability Data 8-Lead MSOP
LT1638CN8#PBF Material Declaration Reliability Data 8-Lead PDIP (Narrow 0.3 Inch)
LT1638CS8#PBF Material Declaration Reliability Data 8-Lead SOIC (Narrow 0.15 Inch)
LT1638CS8#TRPBF Material Declaration Reliability Data 8-Lead SOIC (Narrow 0.15 Inch)
LT1638HS8#PBF Material Declaration Reliability Data 8-Lead SOIC (Narrow 0.15 Inch)
LT1638HS8#TRPBF Material Declaration Reliability Data 8-Lead SOIC (Narrow 0.15 Inch)
LT1638IDD#PBF Material Declaration Reliability Data 8-Lead DFN (3mm x 3mm x 0.75mm w/ EP)
LT1638IDD#TRPBF Material Declaration Reliability Data 8-Lead DFN (3mm x 3mm x 0.75mm w/ EP)
LT1638IMS8#PBF Material Declaration Reliability Data 8-Lead MSOP
LT1638IMS8#TRPBF Material Declaration Reliability Data 8-Lead MSOP
LT1638IN8#PBF Material Declaration Reliability Data 8-Lead PDIP (Narrow 0.3 Inch)
LT1638IS8#PBF Material Declaration Reliability Data 8-Lead SOIC (Narrow 0.15 Inch)
LT1638IS8#TRPBF Material Declaration Reliability Data 8-Lead SOIC (Narrow 0.15 Inch)
Wafer Fabrication Data R334 Reliability Data

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Sample & Buy


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Lead Times


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Evaluation Boards

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Up to two boards can be purchased through Analog.com. To order more than two, please purchase through one of our listed distributors.

Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.