PCM69AU Equivalent & Substitute Parts

Part Overview

The PCM69AU is an 18-bit audio digital-to-analog converter (DAC) manufactured by Texas Instruments, designed for audio applications requiring PCM data interface support. This component operates with dual-channel output and is housed in a 20-SOIC surface mount package. The PCM69AU is classified as obsolete, making identification of functionally compatible alternatives essential for ongoing system support and new design implementations.

Substiute Parts

PCM69AU

Texas InstrumentsIn Stock: 4039PCM69AU Datasheet

Current PartRFQ

PCM1793DB

Texas InstrumentsIn Stock: 2243PCM1793DB Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

The PCM1793DB qualifies as a manufacturer-recommended substitute for the PCM69AU based on the following substitution criteria:

Functional Compatibility Parameters:

• Both components are dual-channel audio DACs from Texas Instruments
• Both support surface mount installation
• Both operate within the same temperature range (-25°C to 85°C)
• Both maintain ROHS3 compliance and MSL 1 rating
• Both are designed for audio signal processing applications

Allowable Parameter Differences:

• Resolution upgrade: 18 bits (PCM69AU) to 24 bits (PCM1793DB) - higher resolution is backward compatible
• Data interface change: PCM to I2S - both are standard audio serial protocols
• Sampling rate: PCM69AU has no specified rate; PCM1793DB supports 200 kHz
• Supply voltage flexibility: PCM69AU requires 5V; PCM1793DB accepts 3V to 3.6V or 5V
• Package change: 20-SOIC to 28-SSOP - both are surface mount with different pin counts
• Product status: Obsolete (PCM69AU) to Active (PCM1793DB) - ensures ongoing availability

Parameter Comparison

Engineering Selection Recommendations

PCM1793DB Substitution Basis:

The PCM1793DB is the manufacturer-recommended substitute for the obsolete PCM69AU. Selection of this alternative is justified by:

1. Product Status Alignment: The PCM69AU's obsolete status necessitates component replacement. The PCM1793DB's active status ensures long-term supply chain viability and manufacturing support.

2. Compliance Continuity: Both components maintain ROHS3 compliance, REACH unaffected status, and identical MSL 1 ratings, ensuring regulatory and environmental requirements remain satisfied.

3. Functional Enhancement: The PCM1793DB provides superior specifications (24-bit resolution versus 18-bit, 200 kHz sampling rate) while maintaining dual-channel audio DAC functionality and identical operating temperature range.

4. Supply Voltage Flexibility: The PCM1793DB accepts both 3V to 3.6V and 5V supplies, providing greater design flexibility compared to the PCM69AU's fixed 5V requirement.

5. Design Integration Considerations: Substitution requires PCB layout modification due to package change (20-SOIC to 28-SSOP) and firmware/interface adaptation for I2S protocol implementation in place of PCM.

Frequently Asked Questions (FAQ)

Q: Can the PCM1793DB directly replace the PCM69AU without PCB modifications?

A: No. The PCM1793DB uses a 28-SSOP package compared to the PCM69AU's 20-SOIC package. PCB layout redesign is required. Additionally, the data interface changes from PCM to I2S, necessitating firmware or interface logic updates.

Q: What is the primary reason for substituting the PCM69AU?

A: The PCM69AU is classified as obsolete, meaning Texas Instruments no longer manufactures or supports this component. The PCM1793DB is an active product with ongoing availability and manufacturer support.

Q: Are there compatibility concerns with the I2S interface change from PCM?

A: Both PCM and I2S are standard serial audio protocols. System compatibility depends on your audio interface implementation. I2S is more widely supported in modern audio systems. Interface adaptation may be required during integration.

Q: Does the 24-bit resolution of the PCM1793DB create compatibility issues with 18-bit audio systems?

A: No. Higher resolution is backward compatible. The PCM1793DB can process 18-bit audio data without functional degradation. The additional 6 bits provide enhanced dynamic range if your audio source supports it.

Q: What are the thermal and environmental operating conditions?

A: Both components operate identically across -25°C to 85°C. Both maintain MSL 1 (unlimited moisture sensitivity level) and ROHS3 compliance, ensuring equivalent reliability in standard industrial and commercial environments.

Q: Is the supply voltage difference between 5V (PCM69AU) and 3V to 3.6V or 5V (PCM1793DB) significant?

A: The PCM1793DB's wider supply range offers design flexibility. If your system uses 5V, both components are compatible. If transitioning to lower voltage supplies (3V to 3.6V), the PCM1793DB enables this option while the PCM69AU does not.

Q: What inventory status should I expect?

A: The PCM69AU has 4,007 pieces in stock as new original inventory. The PCM1793DB has 2,220 pieces in stock. Both are available; however, the PCM1793DB's active status ensures continued manufacturing and restocking, while PCM69AU inventory is finite.