Texas Instruments PCM2902E

Overview

PCM2902E from Texas Instruments is a stereo audio codec IC with integrated USB 1.1 full-speed interface, S/PDIF I/O, 16-bit delta-sigma ADC/DAC, and on-chip clock generator. It operates from a single 5-V bus supply, supports independent adaptive playback and asynchronous record sampling rates (up to 48 kHz), and delivers 96 dB SNR DAC / 89 dB SNR ADC performance in USB audio speaker and headset applications.

For engineers reviewing the PCM2902E datasheet, PCM2902E pinout, PCM2902E application, or PCM2902E equivalent, this page provides verified technical context, validated pin functions, confirmed S/PDIF-enabled stereo audio codec behavior, real-world USB HID control implementation details, and alternative part selection guidance for legacy audio interface designs.

Technical Context

The PCM2902E implements TI's SpAct™ architecture to recover audio clocks directly from USB packet timing, eliminating external crystal oscillators beyond the required 12-MHz reference. Its dual PLL system enables independent jitter-controlled playback and recording paths-adaptive mode for DAC output, asynchronous mode for ADC input-ensuring low-jitter audio streaming without host-side clock synchronization.

It integrates four USB interfaces: standard audio control (IF #0), isochronous-out streaming (IF #1), isochronous-in streaming (IF #2), and HID volume/mute control (IF #3). S/PDIF functionality is implemented via dedicated DIN (input) and DOUT (output) pins, distinct from the PCM2900E variant, and operates at 3.3-V CMOS levels with internal pulldown.

Key Specifications

Pinout & Package

Package: 28-pin SSOP (28DB), 0.65-mm lead pitch, body size 10.2 mm × 5.3 mm, thermal resistance θ_JA = 100°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar stereo USB audio codec applications.

Compared with PCM2900E, the PCM2902E adds S/PDIF I/O without changing package or power requirements; compared with CY7C66113-BZXI, it delivers turnkey audio functionality with zero firmware-reducing time-to-market by ≥8 weeks.

Availability

PCM2902E is available at Aetrix Electronics and suitable for USB audio speaker, USB headset, and USB monitor audio applications requiring stable component supply across industrial temperature ranges and long-lifecycle production programs.

Supply support for PCM2902E includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and connectivity technologies with over 50 years of innovation in precision signal chain solutions.

The PCM2900/2902 product line was designed specifically for cost-sensitive, bus-powered USB audio peripherals-integrating USB protocol handling, high-fidelity audio conversion, and human interface controls into a single SSOP package.

FAQ

What is the primary function of the PCM2902E in a USB audio system?

The PCM2902E serves as a complete stereo audio codec with integrated USB 1.1 interface, performing simultaneous analog-to-digital conversion (ADC) for microphone input and digital-to-analog conversion (DAC) for speaker/headphone output-all managed in hardware without host firmware. Its S/PDIF I/O extends digital audio capability, and SpAct™ clock recovery ensures low-jitter playback independent of host timing. The PCM2902E eliminates need for separate USB controller, DAC, ADC, and clock generator ICs.

Does the PCM2902E require an external crystal oscillator?

Yes-the PCM2902E requires a 12.000 MHz ±8 ppm fundamental-mode crystal connected between XTI (pin 21) and XTO (pin 20) to generate its internal 96-MHz PLL clock. This crystal is essential for USB packet timing recovery and audio sample rate accuracy. No additional oscillators or clock sources are needed, as all internal voltage regulators and audio clocks derive from this single crystal and VBUS supply.

How does the PCM2902E handle USB suspend mode?

The PCM2902E enters low-power suspend mode automatically when the USB host issues a suspend command. During suspend, it draws only 210 µA from VBUS while maintaining descriptor readiness. The SSPND pin (pin 28) asserts low to signal suspend state to external circuitry-enabling designers to gate power to analog stages or LEDs. Upon resume, the device restores full audio functionality without host re-enumeration. This behavior is fully compliant with USB 1.1 power management requirements.

Can the PCM2902E's USB descriptors be customized for OEM branding?

Yes-the PCM2902E supports partial customization of USB descriptors including Vendor ID, Product ID, and string descriptors (e.g., "Burr-Brown from TI" and "USB audio codec"). These are programmed via mask ROM during manufacturing and cannot be field-updated. TI provides mask modification services upon request; OEMs must coordinate changes early in the design cycle. Default values are VID=0x08BB, PID=0x2902, and strings as defined in the SLES035E datasheet.

What are the key differences between PCM2902E and PCM2900E?

The PCM2902E includes dedicated S/PDIF input (DIN, pin 24) and output (DOUT, pin 25) functionality not present in the PCM2900E. All other electrical specifications, pinout, package, USB interface, ADC/DAC performance, and operating conditions are identical. The PCM2900E omits DIN/DOUT pins entirely-making it unsuitable for digital audio passthrough-but otherwise shares full drop-in compatibility for analog-only applications.