The TDC-GPX chip, developed by Acam-Messelectronic and available in North America through Transducers Direct has a resolution as low as 10 ps and a measurement range up to 40 µsec. The new time-to-digital converter is intended for navigation systems, missile defense systems, range finders and speed measurement devices, frequency and phase measurement instruments, and medical imaging scanners.

Operating in M-mode, the GPX's 10‑picosecond resolution translates to a measurement accuracy of ±1 mm rms to a range of 1500 m, with peak-to-peak variation of 70 ps (±5 mm). A peak pulse rate of 182 MHz makes the GPX chip suitable for 3-D laser scanners where a high sampling rate and excellent single-shot resolution are required.

Four selectable operating modes make the GPX suitable for a wide range of applications. In I-mode, the GPX provides eight LVTTL input channels, a resolution of 81 ps, infinite measurement range, and 5.5 ns pulse-pair resolution. G-, R- and M-modes all provide either two LVTTL or two LVPECL input channels. In G-mode, the resolution is 40 ps, the measurement range is 65 µsec, and the minimum pulse-width measurement is 1.5 ns. In R‑mode, the resolution is 27 ps, the measurement range is 40 µsec, and the pulse-pair resolution is 5.5 ns. In M-mode, the resolution is 10 ps rms with a peak-to-peak of 10 ps, and the measurement range is 10 µsec. Current consumption of the GPX typically ranges from 39 mA to 45 mA.

The optional ATMD-GPX PC-based evaluation system allows design engineers to access the power of the GPX chip through a PC interface. The ATMD-GPX consists of hardware that connects to a PC and allows setting of all the relevant registers of the TDC-GPX. The PC communicates directly with the GPX chip at a data rate limited by the software and communication, and the system enables the GPX to collect data at a peak rate of 200 MHz. Measurement data can be displayed directly or as a histogram, as well as exported.

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