DF1760U Equivalent & Substitute Parts

Part Overview

The DF1760U is a 20-bit Sigma-Delta analog-to-digital converter manufactured by Texas Instruments, designed for dual-channel single-ended data acquisition applications. The device features a 48 kHz sampling rate and SPI digital interface, operating from 5V supply rails in a 20-SOIC surface mount package. The DF1760U is classified as obsolete, making identification of functionally compatible alternatives essential for ongoing system support and new design implementations.

Substiute Parts

DF1760U

Texas InstrumentsIn Stock: 2316DF1760U Datasheet

Current PartRFQ

ADS1271IPW

Texas InstrumentsIn Stock: 19964ADS1271IPW Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the DF1760U requires evaluation against the following critical parameters that define functional compatibility:

Resolution & Sampling Performance: The DF1760U operates at 20-bit resolution with a 48 kHz sampling rate. Substitute devices must maintain or exceed these specifications to preserve signal fidelity and data acquisition bandwidth.

Channel Configuration & Input Type: The DF1760U provides 2 single-ended inputs. Substitute devices with reduced input channels or differential-only input architectures require circuit redesign to maintain dual-channel acquisition capability.

Digital Interface & Protocol: The DF1760U uses SPI for serial data communication. Substitute devices must support SPI to ensure compatibility with existing microcontroller interfaces and firmware implementations.

Supply Voltage Requirements: The DF1760U requires 5V for both analog and digital supply rails. Substitute devices with different supply voltage specifications necessitate power distribution modifications.

Package & Thermal Characteristics: The DF1760U uses a 20-SOIC package with MSL 3 rating. Substitute devices in different packages require PCB layout redesign and may have different moisture handling requirements.

Product Status & Compliance: The DF1760U is obsolete. Active substitute devices must maintain ROHS3 compliance and REACH unaffected status to meet current regulatory requirements.

Parameter Comparison

Engineering Selection Recommendations

The ADS1271IPW is the manufacturer-recommended substitute for the DF1760U. Both devices are manufactured by Texas Instruments, employ Sigma-Delta architecture, and support SPI digital communication. Both maintain ROHS3 compliance and REACH unaffected status, meeting current regulatory requirements.

The ADS1271IPW offers enhanced specifications: 24-bit resolution (versus 20-bit), 105 kHz sampling rate (versus 48 kHz), and extended operating temperature range (-40°C to 105°C versus 0°C to 70°C). The device features improved moisture sensitivity (MSL 2 versus MSL 3), reducing handling and storage constraints.

Critical design considerations exist: The ADS1271IPW provides a single differential input channel, whereas the DF1760U provides two single-ended channels. Systems requiring dual-channel acquisition must implement external multiplexing or employ multiple ADS1271IPW devices. The ADS1271IPW digital supply operates at 1.65V to 3.6V, requiring separate low-voltage regulation compared to the DF1760U's 5V digital supply. The ADS1271IPW uses a 16-TSSOP package, necessitating PCB layout redesign from the original 20-SOIC footprint.

Frequently Asked Questions (FAQ)

Q: Can the ADS1271IPW directly replace the DF1760U in existing designs?

A: Direct pin-for-pin replacement is not possible. The ADS1271IPW uses a different package (16-TSSOP versus 20-SOIC), has a single differential input versus dual single-ended inputs, and requires a separate 1.65V to 3.6V digital supply. PCB redesign and firmware modification are required.

Q: What is the impact of the single-channel input on the ADS1271IPW?

A: The DF1760U acquires two independent single-ended signals simultaneously. The ADS1271IPW acquires one differential signal. Dual-channel systems must either implement external analog multiplexing to time-share a single ADS1271IPW or use multiple devices with separate SPI interfaces.

Q: Does the higher resolution of the ADS1271IPW (24-bit versus 20-bit) affect compatibility?

A: Higher resolution is a performance enhancement, not a compatibility issue. Firmware must be updated to handle 24-bit data words instead of 20-bit words. The increased sampling rate (105 kHz versus 48 kHz) also requires firmware adjustment to match the new data rate.

Q: What are the implications of the different digital supply voltage?

A: The DF1760U operates the digital interface at 5V. The ADS1271IPW operates at 1.65V to 3.6V. A separate low-voltage regulator must be added to the power distribution network. Level shifting may be required if the microcontroller SPI interface operates at 5V logic levels.

Q: How do the package differences affect PCB design?

A: The DF1760U uses a 20-SOIC package (0.209" width). The ADS1271IPW uses a 16-TSSOP package (0.173" width). The footprint is smaller but requires PCB layout redesign. Via placement, trace routing, and decoupling capacitor positioning must be re-evaluated for the new package geometry.

Q: Are there any handling or storage differences between these devices?

A: The DF1760U has MSL 3 rating (168 hours floor life). The ADS1271IPW has MSL 2 rating (1 year floor life). The ADS1271IPW has less stringent moisture handling requirements, reducing bake-out procedures and storage constraints during manufacturing.