PCM1750U Equivalent & Substitute Parts

Part Overview

The PCM1750U is an 18-bit audio ADC manufactured by Texas Instruments, designed for dual-channel serial data acquisition applications. This component operates with dual analog and digital supply voltages (±) and is housed in a 28-SOIC surface mount package. The PCM1750U is classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing system support, redesigns, and production continuity.

Substiute Parts

PCM1750U

Texas InstrumentsIn Stock: 2335PCM1750U Datasheet

Current PartRFQ

ADS8381IBPFBT

Texas InstrumentsIn Stock: 1169ADS8381IBPFBT Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the PCM1750U is determined by the following critical parameters:

Resolution Match: 18-bit resolution is the primary functional requirement. Substitute parts must maintain this bit depth to preserve signal fidelity and system accuracy.

Data Interface Compatibility: The PCM1750U uses a serial data interface. Substitute parts may employ alternative data interfaces (parallel, SPI, I²C) provided the system design accommodates the interface change and the receiving circuitry supports the new protocol.

Channel Configuration: The dual-channel (2-channel) architecture is specific to audio applications. Single-channel alternatives may substitute if system requirements permit channel reduction or external multiplexing.

Supply Voltage Compatibility: The PCM1750U operates on dual ±5V supplies. Substitute parts with different supply voltage ranges (2.7V ~ 5.25V digital, 5V analog) are acceptable if the power distribution network can be adapted.

Package and Mounting: Surface mount technology is maintained across alternatives. Package changes from 28-SOIC to 48-TQFP require PCB redesign and layout modifications.

Compliance and Status: Active product status and ROHS3 compliance ensure long-term availability and regulatory alignment.

Parameter Comparison

Engineering Selection Recommendations

ADS8381IBPFBT as Primary Substitute:

The ADS8381IBPFBT maintains the critical 18-bit resolution and operating temperature range of the PCM1750U. Both components are manufactured by Texas Instruments and comply with ROHS3 standards, ensuring regulatory continuity.

The ADS8381IBPFBT is classified as active product status, providing assured long-term availability and manufacturing support compared to the obsolete PCM1750U. The improved moisture sensitivity level (MSL 2 versus MSL 3) offers enhanced reliability during storage and handling.

Design Considerations:

Substitution requires accommodation of interface and channel differences. The ADS8381IBPFBT employs a parallel data interface and single-channel architecture, necessitating system-level modifications to the data acquisition firmware and PCB layout. The package change from 28-SOIC to 48-TQFP requires PCB redesign.

The ADS8381IBPFBT operates with separate analog (5V) and digital (2.7V ~ 5.25V) supply voltages, differing from the PCM1750U dual ± supply configuration. Power distribution network redesign is required.

Frequently Asked Questions (FAQ)

Q: Can the ADS8381IBPFBT directly replace the PCM1750U without PCB modifications?

A: No. The ADS8381IBPFBT requires PCB redesign due to package differences (48-TQFP versus 28-SOIC), different pinout, and parallel data interface versus serial interface. Firmware modifications are necessary to support the new interface protocol.

Q: What is the primary reason for substitution?

A: The PCM1750U is classified as obsolete. The ADS8381IBPFBT is an active product with assured manufacturing availability and improved moisture sensitivity characteristics.

Q: Are both parts compliant with current regulatory standards?

A: Yes. Both the PCM1750U and ADS8381IBPFBT are ROHS3 compliant and REACH unaffected, meeting current environmental and regulatory requirements.

Q: How do the channel configurations differ?

A: The PCM1750U provides dual-channel (2-channel) audio ADC functionality. The ADS8381IBPFBT is a single-channel SAR ADC. Systems requiring dual-channel acquisition must implement external multiplexing or dual ADS8381IBPFBT devices.

Q: What supply voltage changes are required?

A: The PCM1750U operates on dual ±5V supplies. The ADS8381IBPFBT requires separate analog (5V) and digital (2.7V ~ 5.25V) supplies. Power distribution network redesign is necessary.

Q: Is the 18-bit resolution maintained in the substitute?

A: Yes. Both the PCM1750U and ADS8381IBPFBT provide 18-bit resolution, preserving signal acquisition accuracy and system performance.

Q: What is the impact of the data interface change?

A: The PCM1750U uses serial interface; the ADS8381IBPFBT uses parallel interface. Firmware modifications and interface circuitry changes are required to support the new protocol.