THS4140CDGK Equivalent & Substitute Parts

Part Overview

The THS4140CDGK is a differential amplifier integrated circuit manufactured by Texas Instruments, designed for high-speed signal conditioning applications. This device features a single differential amplifier circuit in an 8-VSSOP surface mount package with a gain bandwidth product of 205 MHz and slew rate of 450 V/µs.

The THS4140CDGK is classified as obsolete. Locating equivalent or substitute components is necessary for new designs, production continuity, and long-term system support where the original part is no longer available from primary sources.

Substiute Parts

THS4140CDGK

Texas InstrumentsIn Stock: 909THS4140CDGK Datasheet

Current PartRFQ

AD8421TRMZ-EP

Analog Devices Inc.In Stock: 1489AD8421TRMZ-EP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the THS4140CDGK requires evaluation based on the following critical parameters:

Functional Classification: The THS4140CDGK is a differential amplifier. The substitute part AD8421TRMZ-EP is classified as an instrumentation amplifier, which represents a different functional topology. While both are single-circuit linear amplifiers in compatible surface mount packages, the architectural difference must be considered in circuit design context.

Package Compatibility: Both the main part and substitute part use 8-MSOP (0.118", 3.00mm Width) surface mount packaging, enabling direct physical replacement on printed circuit boards designed for this footprint.

Supply Voltage Range: The THS4140CDGK operates from 4 V to 33 V. The AD8421TRMZ-EP operates from 5 V to 36 V. The substitute part requires a minimum supply voltage of 5 V, which is 1 V higher than the main part.

Operating Temperature Range: The THS4140CDGK operates from 0°C to 70°C. The AD8421TRMZ-EP operates from -55°C to 125°C, providing an extended temperature range suitable for wider environmental conditions.

Compliance and Regulatory Status: Both parts are ROHS3 compliant, REACH unaffected, and carry EAR99 ECCN classification, meeting equivalent regulatory requirements.

Parameter Comparison

Engineering Selection Recommendations

Product Status Consideration: The THS4140CDGK is obsolete, while the AD8421TRMZ-EP is active. Active product status ensures ongoing availability, manufacturing support, and compliance with current regulatory standards.

Regulatory Compliance: Both parts meet ROHS3, REACH, and EAR99 requirements, ensuring equivalent compliance posture for regulated applications.

Supply Voltage Requirement: Applications requiring operation below 5 V cannot use the AD8421TRMZ-EP as a direct substitute. The minimum supply voltage of 5 V for the substitute part must be verified against system power architecture.

Performance Trade-offs: The AD8421TRMZ-EP exhibits significantly lower slew rate (35 V/µs versus 450 V/µs) and reduced bandwidth (10 MHz versus 160 MHz). These differences are material for high-speed signal conditioning applications. The substitute part demonstrates superior input offset voltage (70 µV versus 1 mV) and lower input bias current (1 nA versus 5.1 µA), which are advantageous for precision measurement circuits.

Temperature Range: The extended operating temperature range of the AD8421TRMZ-EP (-55°C to 125°C) accommodates industrial and military applications beyond the original part's specification (0°C to 70°C).

Frequently Asked Questions (FAQ)

Q: Can the AD8421TRMZ-EP be used as a direct pin-for-pin replacement for the THS4140CDGK?

A: Both parts use 8-MSOP surface mount packaging with identical physical dimensions (0.118", 3.00mm Width), enabling direct physical placement on PCBs designed for this footprint. However, functional differences between differential and instrumentation amplifier topologies require circuit-level evaluation before implementation.

Q: What is the primary difference between these two amplifier types?

A: The THS4140CDGK is a differential amplifier designed for high-speed signal conditioning with 450 V/µs slew rate and 205 MHz gain bandwidth product. The AD8421TRMZ-EP is an instrumentation amplifier optimized for precision measurement with lower slew rate (35 V/µs) and bandwidth (10 MHz), but superior input offset voltage and bias current specifications.

Q: Are there supply voltage compatibility issues?

A: The THS4140CDGK operates from 4 V minimum supply voltage. The AD8421TRMZ-EP requires 5 V minimum. Systems operating at 4 V cannot use the substitute part without power supply modification.

Q: How do the bandwidth specifications compare?

A: The THS4140CDGK provides -3dB bandwidth of 160 MHz, suitable for high-frequency applications. The AD8421TRMZ-EP provides 10 MHz bandwidth. Applications requiring bandwidth above 10 MHz cannot use the substitute part.

Q: What are the supply current differences?

A: The THS4140CDGK draws 13.2 mA supply current. The AD8421TRMZ-EP draws 2 mA, representing 85% lower power consumption. This difference is significant for battery-powered or thermally constrained applications.

Q: Is the substitute part suitable for precision measurement applications?

A: The AD8421TRMZ-EP demonstrates superior precision characteristics with input offset voltage of 70 µV (versus 1 mV) and input bias current of 1 nA (versus 5.1 µA). These specifications make the substitute part advantageous for low-level signal measurement where offset and bias current errors must be minimized.

Q: What is the inventory status for each part?

A: The THS4140CDGK has 894 pieces in stock as new original inventory. The AD8421TRMZ-EP has 1400 pieces in stock. Both parts are available for immediate procurement.

Q: Are both parts compliant with current environmental regulations?

A: Both parts are ROHS3 compliant and REACH unaffected, meeting current environmental and hazardous substance restrictions for electronic components.