Design and Implementation of Low-Current Sensing Precision Circuit for Functional Serial Bus Transmission Multi-Site IC Testing

In an integrated circuit (IC), the analog-to-digital converter (ADC) plays a crucial role in enabling serial bus communication for various applications by performing the essential tasks of bridging the gap between the analog and digital systems. Throughout IC testing, ADC test parameters are perquisite for the functional testing of these serial bus protocols necessitating an accurate low-current sensing for fault detection. These ADC device parameters are usually in microunit resolution, often use the conventional I2V converter configuration, which have faced challenges during platform conversion and test site expansion of switch controller ICs due to noise sensitivity, low input offset, and drift. As a resolution, a low-current sensing precision circuit for the loadboard was developed based on AD620 instrumentation amplifier. The implemented solution provides flexible, stable, and more accurate loadboard for concurrent testing. Consequently, it ensured an increase in throughput potential (from single-site to quad-site) and cost efficiency from the legacy platform.