The Acam-Messelectronic TDC-GPX chip from Transducers Direct (Miamiville, OH), allows distance measuring of ±1 mm rms to a range of 1,500 meters. The chip has four selectable operating modes: I-mode provides eight LVTTL input channels, a resolution of 81 picoseconds (ps), infinite measurement range, and 5.5 nanosecond (ns) pulse-pair resolution. G-mode has a 40-ps resolution, a measurement range of 65 μsec, and a minimum pulse-width measurement of 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 a measurement range of 10 μsec. Power consumption ranges from 39 to 45 mA. Applications include navigation systems, speed measurement devices, frequency and phase measurement, and medical imaging systems.