Testing consumer audio and video SOCs.(SOC Test)(Cover Story)

The consumer world is converging, and the lines between consumer, computation, and communications applications continue to blur as more and more functionality appears in each consumer device. For example, cell phones, only one type of device, now include digital cameras, video, Internet and e-mail access, multimedia gaming, short message services, multimedia messaging, MP3 players, digital radio, location services, PDA capabilities, and even broadcast TV.

[ILLUSTRATION OMITTED]

The higher-quality audio and video applications coming to the cell phone require faster sampling rates, wider dynamic range, and an increase in memory. Even in the confines of automobiles, demand for higher-quality audio and video is increasing with multichannel audio and high-resolution location displays using global positioning system (GPS) receivers with DVD information storage.

[FIGURE 1 OMITTED]

The major consequences of this consumer-application convergence are increased system-level integration of RF, mixed signals, high-speed interfaces, power management, memory, and powerful processing. To keep size, cost, and power consumption low, these devices are being manufactured as a system on a chip (SOC) or as a system in a package (SIP). As the functionality and number of different cores increase, so does the number of digital pins to accommodate the needed digital control and data lines.

Industry-Specific Test Demands

The increase in SOC and SIP complexity in the high-volume consumer world conflicts with two fundamental requirements: low cost and shorter device life cycles. Consumers want more performance at the same or lower cost, and they're demanding new improvements more often. The parts must be tested thoroughly but very quickly at low cost.

The additional time to test increased device complexity can be addressed by providing greater parallelism in test while significantly decreasing the throughput overhead of the ATE architecture. To address the challenges of the analog cores now appearing in the leading-edge consumer devices, both of these enhancements must be enabled while maintaining the resolution and accuracy of the ATE hardware.

Audio DAC and ADC

Highly integrated SOC devices, such as the cellular baseband processor in Figure 1, include multiple disparate functional blocks that can be challenging from both a specification and a test time perspective.

The audio quality requirements of previous generations of cellular phones typically could be met by simple digital-to-analog converters (DACs) and analog-to-digital converters (ADCs) with 10-b effective resolution and 4-kHz bandwidth. …

To read the full text of this article and others like it, subscribe today!