How does a multiphase clock Vernier Time to Digital Converter (TDC) improve on-chip temperature measurement?

Multiphase clock Vernier Time to Digital Converters (TDCs) enhance on-chip temperature measurement by leveraging Phase-Locked Loops (PLLs) in FPGAs to generate multiple clock signals with different phases. A clock selection circuit then chooses the phase closest to the incoming pulse edge, triggering the TDC almost immediately. This reduces the maximum error to just ¼ TCLK, a significant improvement over the traditional TCLK error.

Besides measuring time intervals, what other crucial application benefits from using Time to Digital Converters (TDCs)?

Time to Digital Converters (TDCs) are essential in various fields beyond timing, including on-chip temperature measurement. They enable systems to accurately monitor their thermal performance, crucial for maintaining the reliability and performance of modern integrated circuits where managing heat is critical.

What are the limitations of traditional PLL-based TDCs, and how does the multiphase clock Vernier TDC overcome these?

Traditional PLL-based TDCs face accuracy limitations due to delays between the start of a pulse and the initiation of the conversion process, which can be as long as one clock cycle (TCLK). This delay introduces errors that undermine the precision of temperature measurements. The multiphase clock Vernier TDC addresses this by using different phase-shifted clocks to minimize these delays.

What are the essential components of a multiphase clock Vernier TDC system, and what key element is needed for complete temperature sensing?

The key components of the multiphase clock Vernier TDC system include Phase-Locked Loops (PLLs) for multiphase clock generation, a clock selection circuit to choose the optimal clock phase, and the TDC itself, which is triggered by the selected clock. Missing from this description is the temperature sensor that generates the initial time pulse proportional to temperature, which the TDC then measures. The integration of these components allows for precise temperature monitoring across an integrated circuit.

What are the implications of using multiphase clock Vernier TDCs for the future of electronic devices and temperature management?

The ability of the multiphase clock Vernier TDC to deliver high resolution at a low cost makes it an attractive solution for a wide range of applications, including consumer electronics and industrial monitoring systems. This technology ensures the performance and reliability of electronic devices. As technology evolves, such innovations will be crucial in maintaining the integrity of integrated circuits operating under varying thermal conditions.

Unlock Precision: How Multiphase Clock Vernier TDC Revolutionizes On-Chip Temperature Measurement

Elliot Brynn in Tech & Innovation September 2025 • 4 min read.

"Discover the innovative use of FPGA and multiphase clock technology for ultra-precise temperature sensing in integrated circuits—cutting costs and boosting accuracy."

In today's world of advanced technology, measuring time intervals with incredible precision is essential in countless applications. Think about time-of-flight detectors, advanced laser ranging, sophisticated medical imaging, and the precise navigation systems used in aerospace. The ability to accurately convert time pulses into digital data is at the heart of these innovations.

Traditionally, this conversion relied on analog-to-digital converters (ADCs). However, a new approach using Time to Digital Converters (TDCs) directly measures time, offering increased efficiency and precision. Beyond timing, TDCs are now crucial for on-chip temperature measurement, enabling systems to monitor their thermal performance with unparalleled accuracy. This is especially important in modern integrated circuits where managing heat is critical for reliability and performance.

The need for cost-effective, high-resolution temperature monitoring has driven the development of innovative TDC solutions. On-chip thermal monitoring systems typically employ a network of temperature sensors distributed across the integrated circuit. These sensors generate time pulses proportional to the local temperature, which are then measured by a high-resolution TDC. This approach demands TDCs that are not only highly accurate but also stable, thermally insensitive, and easy to calibrate. These requirements are essential to ensure reliable and precise temperature monitoring in diverse applications.

The Multiphase Clock Vernier TDC Advantage: Achieving Unprecedented Precision

Integrated circuit with glowing sensors and clock phases.

Traditional PLL-based TDCs often face limitations in accuracy due to potential delays between the start of a pulse and the initiation of the conversion process. These delays, which can be as long as one clock cycle (TCLK), introduce errors that undermine the precision of temperature measurements.

To address these challenges, a novel method has been developed that leverages the multiphase clock capabilities of Phase-Locked Loops (PLLs) within FPGAs. This innovative approach significantly reduces measurement errors by effectively utilizing different phase-shifted clocks. Here’s how it works:

Multiphase Clock Generation: PLLs are used to generate multiple clock signals with different phases (e.g., 0°, 90°, 180°, and 270°).
Clock Selection: A clock selection circuit intelligently chooses the clock phase whose active edge is closest to the incoming pulse edge. This minimizes the delay before the TDC starts its conversion.
TDC Triggering: The TDC is triggered by the selected clock, ensuring that the measurement begins almost immediately after the pulse arrives.

By selecting the most appropriate clock phase, this method reduces the maximum error to just ¼ TCLK, a significant improvement over the traditional TCLK error. This enhanced precision makes the multiphase clock Vernier TDC ideal for applications requiring highly accurate temperature measurements.

The Future of Precision Temperature Measurement

The multiphase clock Vernier TDC represents a significant advancement in on-chip temperature measurement technology. Its ability to deliver high resolution at a low cost makes it an attractive solution for a wide range of applications, from consumer electronics to industrial monitoring systems. As technology continues to evolve, innovations like this will play a critical role in ensuring the performance and reliability of electronic devices.