ADS1211P Equivalent & Substitute Parts

Part Overview

The ADS1211P is a 24-bit Sigma-Delta analog-to-digital converter manufactured by Texas Instruments, designed for precision data acquisition applications. This device features 4 differential inputs, integrated programmable gain amplifier (PGA), and SPI digital interface. The ADS1211P is classified as obsolete, making identification of suitable substitute components essential for ongoing system support and new design implementations.

Substiute Parts

ADS1211P

Texas InstrumentsIn Stock: 2179ADS1211P Datasheet

Current PartRFQ

ADS1248IPW

Texas InstrumentsIn Stock: 3588ADS1248IPW Datasheet

MFR RecommendedRFQ

ADS1256IDBR

Texas InstrumentsIn Stock: 17231ADS1256IDBR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the ADS1211P is determined by the following critical parameters:

Core Functional Requirements:

• 24-bit resolution maintained across all substitutes
• Sigma-Delta architecture for precision analog-to-digital conversion
• SPI digital interface compatibility
• Programmable gain amplifier (PGA) functionality
• External and internal reference type support

Electrical Compatibility Criteria:

• Supply voltage ranges that accommodate 5V operation
• Operating temperature range covering -40°C to 85°C minimum
• Differential input capability for the primary signal path

Mechanical Considerations:

• Package type change from through-hole to surface-mount introduces PCB layout modifications
• Pin count and pinout differences require schematic and layout redesign

The identified substitutes (ADS1248IPW and ADS1256IDBR) maintain core 24-bit Sigma-Delta ADC functionality with SPI interface and PGA features. Both substitutes are active products with enhanced specifications in sampling rate and supply voltage flexibility, though they require package and mounting type changes from the original through-hole DIP configuration.

Parameter Comparison

Engineering Selection Recommendations

ADS1248IPW Selection Criteria: The ADS1248IPW is an active product offering extended operating temperature range (-40°C to 105°C) and flexible supply voltage operation (2.7V to 5.25V). This substitute provides additional input channel options (4 or 7 inputs) and integrated temperature sensor functionality. The lower sampling rate (2 kSPS) may require evaluation against application timing requirements. Surface-mount packaging necessitates PCB redesign from the original through-hole configuration.

ADS1256IDBR Selection Criteria: The ADS1256IDBR is an active product with the highest sampling rate (30 kSPS) among available substitutes, suitable for applications requiring faster conversion speeds. This device supports up to 8 input channels with both differential and single-ended input configurations. Digital supply voltage range (1.8V to 3.6V) differs from the original 5V specification, requiring power supply architecture modifications. Surface-mount SSOP packaging requires PCB layout changes.

Compliance and Support: Both substitute parts maintain ROHS3 compliance and REACH unaffected status, consistent with the original ADS1211P. Active product status ensures ongoing manufacturer support, documentation availability, and supply chain continuity.

Frequently Asked Questions (FAQ)

Q: Can the ADS1248IPW directly replace the ADS1211P in existing designs? A: Direct socket replacement is not possible due to package type change from 24-DIP through-hole to 28-TSSOP surface-mount. PCB redesign and schematic modifications are required. Functional compatibility exists for 24-bit Sigma-Delta ADC operation with SPI interface and PGA features.

Q: What is the primary difference between ADS1248IPW and ADS1256IDBR substitutes? A: The ADS1248IPW operates at 2 kSPS sampling rate with extended temperature range to 105°C, while the ADS1256IDBR operates at 30 kSPS with standard temperature range to 85°C. The ADS1256IDBR offers higher conversion speed; the ADS1248IPW offers broader temperature operation and integrated temperature sensing.

Q: Are supply voltage differences between substitutes critical? A: Yes. The ADS1248IPW accepts 2.7V to 5.25V analog and digital supplies, providing flexibility for mixed-voltage systems. The ADS1256IDBR requires 5V analog supply but accepts 1.8V to 3.6V digital supply, necessitating separate digital power regulation. Original ADS1211P requires fixed 5V for both supplies.

Q: Does the increased input channel count on substitutes affect compatibility? A: The ADS1248IPW and ADS1256IDBR offer optional additional input channels (7 and 8 respectively) beyond the original 4-channel configuration. Designs utilizing only 4 channels remain compatible; additional channels are unused. Single-ended input capability on substitutes provides flexibility not present in the differential-only ADS1211P.

Q: What packaging considerations apply to these substitutes? A: Both substitutes require surface-mount assembly, eliminating through-hole PCB routing used in the original 24-DIP design. The ADS1248IPW uses 28-TSSOP package (0.173" width); the ADS1256IDBR uses 28-SSOP package (0.209" width). Thermal management and PCB layout strategies differ from through-hole implementations.

Q: Are all three devices RoHS compliant? A: Yes. The ADS1211P, ADS1248IPW, and ADS1256IDBR are all ROHS3 compliant with REACH unaffected status, meeting environmental regulatory requirements for electronic component manufacturing and use.