TIME TO DIGITAL CONVERTERS

Time-to-Digital Converters

Time-to-digital converters (TDCs) are devices used to measure time intervals from less than 1ns to several seconds with resolution as fine as 10ps. The first time-to-digital converters were developed for scientific and research purposes. They were considered a combination of a time-to-analog (TAC) and analog-to-digital (ADC) converter.

The ScioSense (previously acam) Time to Digital Converters are used in applications that were previously analog based. They offer much higher resolution and lower current consumption than their analog counterparts. This low current consumption makes these time to digital converters ideal for wireless applications.

Advantages

  • Ultra Low Current Consumption with standby current as low as only few µA.
  • Up to 8 STOP Channels
  • Automatic Calibration of the Measured Value
  • External Reference Clock in the Range of 1 to 40 MHz.

Products

Integrated Digital Time To Digital Converters

Thanks to modern CMOS-technology it is possible to integrate fully digital time to digital converters into a single chip. The high precision of the digital time measurement—with resolution down to 10ps—in combination with the large dynamic range (up to 30 Bit), the high stability over temperature and supply voltage and the possibility of low cost production thanks to the CMOS technology make them the first choice for industrial applications.

Additional Information

TDC MEASURING METHOD

INTEGRATED DIGITAL TIME-TO-DIGITAL CONVERTERS

Digital TDCs are integrated circuits for high precision time interval measurement, and this is done without any analog components. These time-of-flight sensors became real, thanks to the innovations in semiconductor technology made over the years. They use the propagation delays of simple logical gates (i.e. inverters) for fine quantization of time intervals. Due to the enormous achievements in signal speed, especially in the CMOS sector, it has become possible to implement such TDCs in standard CMOS technology with a resolution in the picosecond range. Nowadays we can integrate system solutions into a single chip that is efficient, low power, space-saving, and low cost.

Digital TDCs can be split into two groups:

  • Absolute delay time TDCs
  • Relative delay time TDCs

ABSOLUTE DELAY TIME TDC

This type of time-to-digital converter uses the absolute propagation time of signals through simple logical elements for fine quantisation of time intervals. (see figure below)

In other words, it determines how many inverter cycles the measured time interval consists of. The figure shows the principle of operation. Clever circuit set-ups, redundant elements and special layout methods on the chip enable the exact reconstruction of the number of basic time intervals. The resolution strictly depends upon the basic delay time in the chip. Resolutions in the range of 14 -100 ps can be achieved by a simple set-up of the measuring core and the use of a state-of-the art CMOS process. The propagation delay itself depends on temperature and supply voltage. Therefore the measured value must be calibrated. This is done by measuring one and two periods of a reference oscillator. Ideally this measurement and the following calculation is done by the TDC itself.

Absolute delay time TDCs have the following advantage:

  • The delay time of the inverter can be precisely adjusted and stabilized by using a phase controlled loop (PLL). It is independent from supply voltage and temperature.
  • Good pulse-pair resolution
  • Multi-hit capability

Customer-specific Integrated TDCs

The use of pure digital circuit design makes it easy to build on the performance features of the standard products and improve specific technical data. Accordingly, ScioSense (previously acam) develops optimized TDC’s which are tailored to the specific measuring requirements of the customer.

  • Additional measuring modes
  • Additional mathematical operations for on-chip data processing (e.g. high performance 32 floating point units with focus on low power consumption)
  • Memory (FIFO, EEPROM…)
  • Various interfaces
  • µC cores

The wealth of experience ScioSense (previously acam) has gathered assures the ability to integrate all necessary functions on a single circuit and so to provide a system-on-chip solution.

Implementation Examples

TDC-S1 is a TDC with 25ps standard deviation for use in the ATV (Automatic Transport Vehicle) that will supply the ISS (International Space Station). The high resolution is all the more impressive as this TDC is realized on a radiation hard process.

DFA1 Integrated circuit for detection of the rotation of a propeller meter with extremely low current consumption (<2uA) – contacless, non-magnetic und feedbackless.

Customer-specific Systems

On the base of the ATMD-System we also develop complete solutions and additional modules to fit your application.

Take as an example the AM-HM1 histogramming module, that was developed for RoentDek. This is a standalone PC-based 4-channel TDC with 32MB Histogram memory for fast readout of Delay-Line-Detectors developed by RoentDek. For more information, please contact RoentDek.

Another example is the Time-of-Flight Module offered by GPTA (Gesellschaft für physikalisch-technische Anwendungen). The key features of this module are virtually dead time free operation, 5 ns multihit dead time in 1 channel mode, (60±5) ps maximum resolution, an input for multicard coincidence measurements. For more information, please email sales@gpta.de

precision-measurement-tdc-cust-spec-tof-mod

Time-of-flight Module

precision-measurement-tdc-cust-spec-space
TDC-SI Module
precision-measurement-tdc-cust-spec-histogramming1
AM-HMI-Histogramming Module

Documentation & Downloads

Software

Description

Software TDC-GPX2:
Evaluation software package for GPX2 (incl. doc, cfg, drv)

Version

V1.0.5

Size

206MB

Download

precision-measurement-tdc-gpx2-evalsw-v1-0-5-0.zip

Description

Software TDC-GP22:
STM32 µC Sample code of Application Note 034

Version

 

Size

42kB

Download

GP22_main_AN034.c

Description

Software TDC-GP22:
Software package for GP22-EVA-KIT

Version

V1.9

Size

111MB

Download

CD-GP22-EVA-XP-WIN7.zip

Description

Software TDC-GP21:
Software package for GP21-EVA-KIT

Version

V3.9

Size

104MB

Download

CD-GP21-EVA-XP-WIN7.zip

Description

Software TDC-GPX:
Evaluation software for ATMD-GPX

Version

V4.0

Size

18MB

Download

ATMD-GPX.zip

Description

Software TDC-GPX:
Visual-C++ sample code for ATMD-GPX

Version

 

Size

214kB

Download

ATMD-GPX-C-samples.zip

Description

Software ATMD-PCI:
Driver files for ATMD-PCI interface card

Version

 

Size

2kB

Download

AcamAtmdPci.zip

Description

Software PICOPROG V3.0 (V2.0):
Driver Installer Stand-Alone

Version

R11

Size

5MB

Download

PicoProg_v2_Driver_Installer_Stand-Alone.zip

Description

Software National Instruments:
NI VISA runtime engine for Windows XP

Version

V3.2

Size

14MB

Download

ni-visa.zip

Description

Software National Instruments:
NI VISA runtime engine for Windows XP

Version

V3.2

Size

14MB

Download

ni-visa.zip

Description

Software National Instruments:
NI VISA runtime engine for Windows 7

Version

V4.62

Size

53MB

Download

visa462runtime.exe

Description

Software National Instruments:
NI VISA runtime engine for Windows Vista

Version

V4.1

Size

41MB

Download

visa410full.exe

Description

Software National Instruments:
NI VISA runtime engine for Windows XP

Version

V3.2

Size

14MB

Download

visa320runtime.exe

Description

Software National Instruments:
NI VISA runtime engine for Windows 98

Version

V2.6

Size

8MB

Download

visa260runtime.exe

 

Software

Description

Software TDC-GPX2:
Evaluation software package for GPX2 (incl. doc, cfg, drv)

Version

V1.0.5

Size

206MB

Download

precision-measurement-tdc-gpx2-evalsw-v1-0-5-0.zip

Description

Software TDC-GP22:
STM32 µC Sample code of Application Note 034

Version

 

Size

42kB

Download

GP22_main_AN034.c

Description

Software TDC-GP22:
Software package for GP22-EVA-KIT

Version

V1.9

Size

111MB

Download

CD-GP22-EVA-XP-WIN7.zip

Description

Software TDC-GP21:
Software package for GP21-EVA-KIT

Version

V3.9

Size

104MB

Download

CD-GP21-EVA-XP-WIN7.zip

Description

Software TDC-GPX:
Evaluation software for ATMD-GPX

Version

V4.0

Size

18MB

Download

ATMD-GPX.zip

Description

Software TDC-GPX:
Visual-C++ sample code for ATMD-GPX

Version

 

Size

214kB

Download

ATMD-GPX-C-samples.zip

Description

Software ATMD-PCI:
Driver files for ATMD-PCI interface card

Version

 

Size

2kB

Download

AcamAtmdPci.zip

Description

Software PICOPROG V3.0 (V2.0):
Driver Installer Stand-Alone

Version

R11

Size

5MB

Download

PicoProg_v2_Driver_Installer_Stand-Alone.zip

Description

Software National Instruments:
NI VISA runtime engine for Windows XP

Version

V3.2

Size

14MB

Download

ni-visa.zip

Description

Software National Instruments:
NI VISA runtime engine for Windows XP

Version

V3.2

Size

14MB

Download

ni-visa.zip

Description

Software National Instruments:
NI VISA runtime engine for Windows 7

Version

V4.62

Size

53MB

Download

visa462runtime.exe

Description

Software National Instruments:
NI VISA runtime engine for Windows Vista

Version

V4.1

Size

41MB

Download

visa410full.exe

Description

Software National Instruments:
NI VISA runtime engine for Windows XP

Version

V3.2

Size

14MB

Download

visa320runtime.exe

Description

Software National Instruments:
NI VISA runtime engine for Windows 98

Version

V2.6

Size

8MB

Download

visa260runtime.exe

 

precision-measurement-ordering-drawing-qfn32
precision-measurement-ordering-drawing-tqfp44
precision-measurement-ordering-drawing-tqfp100

Ordering Numbers

Type Part number Package RoHS compl. Shipping package
TDC-GP22:
TDC-GP22 MNR 1949 QFN32 Yes Tray
TDC-GP22 MNR 1950 QFN32 Yes Tape & Reel (5k)
GP22-EVA-KIT MNR 1951 System Yes Box
GP22-DEMO-KIT MNR 1979 System Yes Box
TDC-GP21:
TDC-GP21 MNR 1839 QFN32 Yes Tray
TDC-GP21 MNR 1720 QFN32 Yes Tape & Reel (3K/5K)
GP21-EVA-KIT MNR 1781 System Yes Box
TDC-GP2:
TDC-GP2 MNR 1058 QFN32 Yes Tray
TDC-GP2 MNR 1480 QFN32 Yes Tape & Reel (2k)
TDC-GP1:
TDC-GP1 MNR 278 TQFP44 Yes Tray
TDC-GPX:
TDC-GPX MNR 975 TQFP100 Yes Tray
TDC-GPX-FG MNR 1089 TFBGA120 Yes Tray

Ordering Numbers

Type Part number Package RoHS compl. Shipping package
TDC-GP22:
TDC-GP22 MNR 1949 QFN32 Yes Tray
TDC-GP22 MNR 1950 QFN32 Yes Tape & Reel (5k)
GP22-EVA-KIT MNR 1951 System Yes Box
GP22-DEMO-KIT MNR 1979 System Yes Box
TDC-GP21:
TDC-GP21 MNR 1839 QFN32 Yes Tray
TDC-GP21 MNR 1720 QFN32 Yes Tape & Reel (3K/5K)
GP21-EVA-KIT MNR 1781 System Yes Box
TDC-GP2:
TDC-GP2 MNR 1058 QFN32 Yes Tray
TDC-GP2 MNR 1480 QFN32 Yes Tape & Reel (2k)
TDC-GP1:
TDC-GP1 MNR 278 TQFP44 Yes Tray
TDC-GPX:
TDC-GPX MNR 975 TQFP100 Yes Tray
TDC-GPX-FG MNR 1089 TFBGA120 Yes Tray