Embedded Test Instrument Research Articles

A Fully-Digital BIST Wrapper Based on Ternary Test Stimuli for the Dynamic Test of a 40 nm CMOS 18-bit Stereo Audio $\Sigma\Delta$ ADC

This paper proposes a fully-digital BIST architecture for the dynamic test of $\Sigma\Delta$ ADCs. The proposed BIST relies on generating a ternary stream that encodes a high-linearity analog sinusoidal and injecting it directly at the input of the $\Sigma\Delta$ modulator. Compared to the well-known bitstream, the use of three logic levels in the ternary stream reduces the quantization noise and, thereby, results in a test with a higher dynamic range that covers the full scale of the ADC. The output response is analyzed on-chip using a simplified version of the sine-wave fitting algorithm to compute the SNDR. A standard SPI bus provides digital external access to the embedded test instruments. The proposed BIST wrapper has been integrated into a 40 nm CMOS 18-bit stereo audio $\Sigma\Delta$ ADC IP core provided by ST Microelectronics. It incurs an overall area overhead of 7.1% and the total test time is 28 ms per channel. Experimental results on fabricated chips demonstrate an excellent correlation between the BIST and the standard functional specification test.

Digital Embedded Test Instrument for On-Chip Phase Noise Testing of Analog/RF Integrated Circuits

This paper presents a digital embedded test instrument (ETI) for on-chip phase noise (PN) testing of analog/RF integrated circuits. The technique relies on 1–bit signal acquisition and dedicated processing to compute a digital signature related to the PN level. An appropriate algorithm based on on-the-fly processing of the 1-bit signal is defined in order to implement the BIST module with minimal hardware resources. Its implementation in CMOS 140[Formula: see text]nm technology occupies only 7,885[Formula: see text][Formula: see text]m2, which represents an extremely small silicon area. Hardware measurements are performed on an FPGA prototype that validates the proposed instrument.

Implementation of Data Communication of a Food Safety Testing Instrument<sup></sup>

In order to make the food safety testing instrument more flexible and convenient and process a lot of data, combining the advantages of the VB interface design and MATLAB secondary development, the serial communication software is developed based food safety testing instrument. The test data is uploaded to computer through RS232 serial port. The research staff needs only to input the parameters simply, and all the parameters were automatically matching with the testing instrument, the test data reception, processing, preservation, search and delete functions was completed through VB calling MATLAB. The software has the abilities of friendly interface, easy to use, high stability, and can shield and correct the misuse of users. It has high value in engineering and can be widely used in similar embedded test instrument.

Time-Based Embedded Test Instrument with Concurrent Voltage Measurement Capability

A scalable low -overhead on-chip instrument is proposed for analog and mixed-signal (AMS) systems-on-chip (SOC) testing, capable of making concurrent low-frequency voltage measurements. It addresses the limitation of parallel testing while reducing the test cost associated with automatic test equipment (ATE). The architecture is based on the distributed voltage-to-time conversion, followed by centralized time-to-digital conversion processes. The voltage to time conversion is achieved using the pulse-width modulation, via network of multiple sensors deployed throughout the SOC. Outputs of the time-to-digital converter are accessed via serial communication bus. Ease of scalability of instrument’s capabilities to perform more concurrent voltage measurements outweighs the fact that it does not achieve high sampling rates. An optional multiplexing scheme reduces size of the test bus that has to be routed around the CUT. Implemented instrument, with 14 sensors, is evaluated in a test case that involves multiple linear and switch mode circuits.