LM71CISD Temperature Sensor - Equivalent & Substitute Parts

Part Overview

The LM71CISD is a digital temperature sensor manufactured by Texas Instruments, designed for local temperature measurement across the range of -40°C to 150°C with 13-bit resolution. The device communicates via SPI interface and operates on supply voltages between 2.65V and 5.5V. This part is currently classified as obsolete, which necessitates identification of functionally equivalent alternatives for ongoing system support and new designs requiring this sensor category.

Substiute Parts

LM71CISD

Texas InstrumentsIn Stock: 1251LM71CISD Datasheet

Current PartRFQ

LM71CISD/NOPB

Texas InstrumentsIn Stock: 1479LM71CISD/NOPB Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the LM71CISD is determined by strict equivalence across the following parameters:

• Sensor Type & Measurement Range: Digital local temperature sensing from -40°C to 150°C
• Resolution & Accuracy: 13-bit resolution with 1.5°C accuracy specification
• Interface Protocol: SPI communication standard
• Electrical Specifications: Supply voltage 2.65V to 5.5V compatibility
• Physical Form Factor: 6-WDFN package with exposed pad in 3x3mm footprint
• Functional Features: Shutdown mode capability

The LM71CISD/NOPB qualifies as a direct substitute based on identical electrical, functional, and mechanical parameters. The primary distinction is packaging configuration and product status.

Parameter Comparison

Engineering Selection Recommendations

The LM71CISD/NOPB is the direct functional equivalent of the LM71CISD. Both parts share identical electrical specifications, sensor characteristics, and physical packaging. The LM71CISD/NOPB is preferred for new designs and ongoing production due to its active product status and ROHS3 compliance certification. The primary difference is packaging format: LM71CISD/NOPB is supplied in Tape & Reel configuration, which is standard for automated assembly processes.

For applications currently using the obsolete LM71CISD, transition to LM71CISD/NOPB requires no circuit redesign or firmware modification, as all functional and electrical parameters remain identical.

Frequently Asked Questions (FAQ)

Q: Can LM71CISD/NOPB be used as a direct replacement for LM71CISD?

A: Yes. Both parts are electrically and functionally identical. The LM71CISD/NOPB is the active production variant with improved compliance status.

Q: What is the difference between LM71CISD and LM71CISD/NOPB?

A: The primary differences are product status (obsolete vs. active), packaging format (bulk vs. Tape & Reel), and RoHS compliance level. All electrical and functional specifications are identical.

Q: Is the 6-WSON package compatible with 6-WDFN footprints?

A: Yes. The 6-WSON (3x3) and 6-WDFN Exposed Pad designations refer to the same physical package form factor used in this product line.

Q: What are the key parameters that determine substitution eligibility?

A: Substitution is based on sensor type, temperature measurement range (-40°C to 150°C), 13-bit resolution, SPI interface, 2.65V to 5.5V supply voltage compatibility, 1.5°C accuracy specification, and 6-WDFN package form factor.

Q: Does the Tape & Reel packaging affect circuit performance?

A: No. Tape & Reel is a supply format for automated assembly. Once soldered to the PCB, the component performs identically to bulk-packaged variants.

Q: Are there any compliance considerations when switching from LM71CISD to LM71CISD/NOPB?

A: The LM71CISD/NOPB offers ROHS3 compliance, which may be required for certain applications or markets. The original LM71CISD is RoHS non-compliant. Both maintain REACH Unaffected status.