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  • 2 stop channels with 5 ns / 20 ns pulse-to-pulse spacing
  • Maximum 70 MSPS per LVDS output
  • Event assignment thanks to reference clock & index simplifies coincidence measurements
  • Single shot accuracy 20 ps RMS resolution per channel, 10 ps RMS with high resolution option
  • Easy pulse width measurements
  • Unlimited measuring range 0s to 16s
  • High efficiency thanks high sample rate
  • Differential reference clock input 2 MHz to 12.5 MHz, optional with quartz
  • Compact design thanks to small package and low number of external components
  • LVDS inputs and outputs, 16-stage FIFO per channel, SPI compatible 4-wire interface for configuration, optionally to be used for data readout
  • Reduced cooling thanks to low power consumption
  • Automatic calibration to reference clock
  • Supply voltage 3.3 V
  • Power dissipation up to 450 mW, standby current 60 μA
  • QFP48 package (7 x 7 mm², 9 × 9 mm² with leads)



  • Simple data post-processing thanks to calibrated results


Product parameters

Resolution [ps]
Pulse-Pair Resolution [ns]
Measurement Rate [MSPS]
Multi-Hit Capability
Operating Supply Range [V]
2.4 to 3.6
Ambient Temperature Range [°C]
-40 to 125


  • Laser rangefinders
  • Automated test equipment
  • Medical imaging
  • ToF spectroscopy

Related Products

Product name
TDC-GPX2 Time-to-Digital Converter

The TDC-GPX2 is the most powerful member in our TDC family. Highest measurement performance and highest data throughput is achieved with LVDS stop inputs and LVDS serial output for each channel. Current saving operation is also possible with CMOS inputs and SPI readout. High configuration flexibility covers many applications. Applications range from gaming, portable handheld laser range equipment to ambitious time-of-flight of highest performance, such as in medical imaging applications. GPX2 operates without any locked loop technologies. All stop event measurement times are calibrated inside the GPX2 proportional to the applied reference clock. Combinations of best single-shot accuracy of 10ps with lowest pulse-to-pulse spacing 5ns and maximum data throughput rate 70 MBPS per stop input are possible.

Product name
AS6500 Time-to-Digital Converter

The AS6500 is a high performance time-to-digital converter (TDC) frontend device. It is a derivative of TDC-GPX2, with CMOS inputs and serial SPI output only. It comes in a QFN40 package. AS6500 achieves high measurement performance and high data throughput. High configuration flexibility and unlimited measurement range cover many applications, ranging from portable handheld laser range equipment to ambitious time-of-flight measurements of high performance. It calculates calibrated stop measurements, referenced to the applied reference clock. Combinations of single shot accuracy of 10ps with lowest pulse-to-pulse spacing <5ns and maximum data input burst rate of 70 MSPS per stop input are possible. Total data throughput via SPI is about 1.5 MSPS.