[time-nuts] Did a member of time-nuts buy this?

[Mike Monett]

> Hi

>> On Dec 10, 2014, at 11:12 PM, Mike Monett
>> <timenuts at binsamp.e4ward.com> wrote:

[...]

>>>> Can you tell me some of the ones that do?

>>> I have yet to see one for under $2K that does it correctly. I
>>> don't have the cash to buy ones at those sort of prices. Some
>>> have reported that the old Motorola UT's will do it. The samples
>>> I have tried have not done very well. I may have not had them
>>> running right who knows.

>> OK, that pretty much eliminates the NIST data.

> or means that more research is needed on single sat boards. There
> are a *lot* of them out there.

What is a "single sat board" and can you give some examples?

>>>>> 5) Feed that into your control loop equation.

>>>> There's another term I need to research!

>>> It's not a simple control process, but it's not all that
>>> terrible either. It just takes a bit of work to optimize. Figure
>>> a few months to a few years for the optimization depending on
>>> what you have for issues along the way.

>>>> OK, so I figure out how to do this. How do I tell if this is
>>>> making the gpsdo more accurate? In other words, how do I get
>>>> the ADEV without having an H-Maser?

>>> You get a Cs (or other atomic standard) or you compare several
>>> different GPSDO's against each other. The preference would be
>>> for groups of three so you can rule out ones that are not doing
>>> what they should.

> The ideal would be > 3 TBolts, > 3 same model Rb's, > 3 same model
> OCXO's and more than three groups overall. Each has their own ADEV
> curve. Comparing devices with vastly different ADEV is not the
> best way to go.

Yes, that makes good sense.

[...]

>> There are many new dacs, op amps, and bipolar microwave devices
>> that offer much lower noise than current designs use. I think the
>> performance can be improved in some areas with new components and
>> design techniques, and I have equipment and time to explore.

> There are only two points that system noise really comes into the
> GPSDO design:

> 1) The TDC must have enough resolution

> 2) The DAC on the EFC must have noise below the OCXO

I was more thinking of the Rubidium physics package. Most of the
Rubidiums on eBay are pretty old.

The lamp must have constant intensity. The null detector has to
identify a very shallow drop. The microwave signal needs to have
excellent phase noise.

These all need low noise, low flicker components, and significant
advances have been made in recent years. The surrounding circuitry
could probably benefit from a redesign to take better advantage of
low noise components. For example, SRD's are much noisier than NLTL's.

Probably little can be done to improve the Rubidium cell, but it
should be the limiting factor and not the electronics.

> The TDC is limited by the basic resolution of the GPS system. It's
> easy to build one that has far more resolution than needed /
> useful.

Some people have little faith:)

> The DAC issue is normally solved with a < $4 part. Unless you have
> an OCXO with a very wide EFC range, it's noise is unlikely to be
> an issue. DAC resolution can be addressed to any desired level
> with two DAC's (fine and coarse). (Once you get going, you only
> use the fine DAC).

> The real "fun and games" revolves around the software used to
> implement the filtering / control loop between the GPS and the
> OCXO (or Rb, or TCXO, or MEMS, or VCXO, or Cs or  )

> Focus on the software.

> Bob

I have a few Rubidiums and OCXOs I'd like to get running for a month
or so to stabilize. During this time, I'd like to monitor the
performance to discover any bad units and see which are the best
ones.

For example, TVB shows a 100:1 variation in ADEV in FE-405B
Rubidiums. The section is titled "Variation in FE-405B" in

http://leapsecond.com/pages/fe405/

Clearly, it would be futile to try to use a bad unit in setting up a
gpsdo.

I need some means of measuring the performance of these units while
they are running. A dozen HP5370's would be out of the question. I
did some research to find the different methods available and decide
which has the lowest per-channel cost and best performance.

Here are some of the references I found. I discarded most of the poor ones
and tried to keep only the ones that talk about measurements in the
picosecond or femtosecond range.

I did not include DMTD since the concept is so simple. The Reviews help to
get oriented, but sometimes it takes reading the papers and the patents to
see the timing diagrams and understand what the author is trying to do.

There are many different variations on the FPGA approach. I would be
concerned about the development time, the large DNL, and the problems with
crosstalk on multi-channel units.

The TI THS788 looks good on paper, but it is single-source, not well
stocked, and there is lttle information on crosstalk between channels. It
is also quite expensive per channel. There are no application notes and
little or no information on usage on the web.

The Thesis generally have excellent reviews worth reading.

Articles

Simple PICTIC 250ps time interval counter
http://www.ko4bb.com/dokuwiki/doku.php?id=precision_timing:pictic

Griffiths Time to Digital converters
http://www.ko4bb.com/~bruce/TDC.html

[time-nuts] Experience with THS788 from TI?-
Attila Kinali's post on TDC methods
https://www.febo.com/pipermail/time-nuts/2012-March/065337.html

Reviews

Review of methods for time interval measurements with picosecond
resolution
http://ztc.wel.wat.edu.pl/met4_1_004.pdf

Low resource FPGA-based 32 Channel Time to Digital Converter
- Excellent review of TDC techniques and measurement verification
http://arxiv.org/vc/arxiv/papers/1206/1206.0679v3.pdf

Design, construction and tests of a high resolution, high dynamic
range Time to Digital Converter
- Excellent review of TDC methods and test techniques
http://inspirehep.net/record/1313667/files/getfile.pdf

Review Of Sub-Nanosecond Time-Interval Measurements
http://www.slac.stanford.edu/cgi-wrap/getdoc/slac-pub-1331.pdf

Chapter 1 Time Interval Measurement Literature Review
http://www.rrsg.ee.uct.ac.za/members/jon/activities/timcs.pdf

Time intervals measurements and generation methods review
http://www.ohwr.org/attachments/128/Time_Interval_Measurements_Techniques.pdf

Papers

A Cyclic CMOS Time-to-Digital Converter With Deep Sub-nanosecond
Resolution
http://ntur.lib.ntu.edu.tw/bitstream/246246/2007041910021548/1/00777354.pdf

A 96-Channel FPGA-based Time-to-Digital Converter
http://arxiv.org/pdf/physics/0502062.pdf

Complete and Compact 32-Channel System for Time-Correlated
Single-Photon Counting Measurements
http://ieeexplore.ieee.org/ielx7/4563994/6588410/06617673.pdf?arnumber=6617673

Design and Development of GPS Receiver for PNSS-1
http://www.suparco.gov.pk/pages/presentations-pdf/day-1/session-2/12C-II/1.pdf

A Novel Ultra-fast High Resolution Time-domain EMI Measurement
System based on Field Programmable Gate Arrays
https://mediatum.ub.tum.de/doc/1163324/1163324.pdf

High Precision Frequency Measurement System Based on Different
Frequency Phase Processing (in Chinese)
http://xbzrb.tjujournals.com/oa/pdfdow.aspx?Type=pdf&FileName=11acd53a-876d-4ab0-8906-572aa3836215.pdf

A 51-dB SNDR DCO-Based TDC Using Two-Stage Second-Order Noise Shaping
http://www28.cs.kobe-u.ac.jp/pdf/1205_konishi_iscas.pdf

Integrated High-Resolution Multi-Channel Time-to-Digital Converters
(TDCs) for PET Imaging
- Discusses 100 fs Gated-ring-oscillator (GRO)
http://cdn.intechopen.com/pdfs-wm/12913.pdf

A 26 ps RMS time-to-digital converter core for Spartan-6 FPGAs
http://arxiv.org/pdf/1303.6840v1.pdf

A High-Resolution Flash Time-to-Digital Converter Taking Into
Account Process Variability
http://conferences.computer.org/async2007/PRS/15-minas-async07.pdf

Principles and Instrumentation in Time-of-flight Mass Spectrometry
http://www.wiley.com/legacy/wileychi/ms/articles/1519_a.pdf

TEMPERATURE SENSING CRYSTAL HTS-206
- maybe more stable than thermistor
http://www.abcelectronique.fr/composants/telechargement_datasheet.php?id=385911&part-number=HTS-206

A novel method of measurement of time and amplitude of analog
signals based solely on FPGA units
http://koza.if.uj.edu.pl/pet-symposium-2013/talks/17.pdf

A 16 channel high resolution (<11 ps RMS) Time-to-Digital Converter
in a Field Programmable Gate Array
http://iopscience.iop.org/1748-0221/7/02/C02004/pdf/1748-0221_7_02_C02004.pdf

A 128-channel Time-to-Digital Converter (TDC) inside a Virtex-5 FPGA
on the GANDALF module
http://iopscience.iop.org/1748-0221/7/03/C03008/pdf/1748-0221_7_03_C03008.pdf

FPGA Based Data Digitisation with Commercial Elements
http://indico.scc.kit.edu/indico/getFile.py/access?contribId=4&sessionId=4&resId=0&materialId=slides&confId=21

Time-to-Digital Converter Architecture with Residue Arithmetic and
its FPGA Implementation
http://www.el.gunma-u.ac.jp/~kobaweb/news/pdf/2014/2014-11li_congbing2.pdf

An FPGA-Integrated Time-to-Digital Converter Based on a Ring
Oscillator for Programmable Delay Line Resolution Measurement
- 0.4 ps Xilinx FPGA
http://downloads.hindawi.com/journals/jece/2014/230803.pdf

First Order Noise Shaping Local-Oscillator Based Time-to-Digital Converter
- Gated Ring Oscillator based TDC
http://ims.unipv.it/~franco/ConferenceProc/313.pdf

A High Resolution FPGA-based TDC with Nonlinearity Calibration
http://www2.ess.nthu.edu.tw/~cwlu/conference/5_A%20High%20Resolution%20FPGA-based%20TDC%20with.pdf

A Single-Slope 80MS/s ADC using Two-Step Time-to-Digital Conversion
http://dspace.mit.edu/openaccess-disseminate/1721.1/60073

Simulation of ps-Detector Electronics
http://hep.uchicago.edu/workshops/2005-picosecond/8-Fukun_Tang_ps_sim.ppt

High Precision Time and Frequency Counter for Mobile Applications
http://www.wseas.us/e-library/transactions/circuits/2010/89-747.pdf

Time-to-Digital Converter based on Analog Time Expansion for 3D Time
of Flight Cameras
https://pure.ltu.se/portal/files/95016947/90220A.pdf

A Pc-Based Time Interval Counter With 200 Ps Resolution
http://www.dtic.mil/get-tr-doc/pdf?AD=ADA427911

The Development of Large-area, Picosecond Resolution, Time-of-Flight
Detectors
http://hep.uchicago.edu/~frisch/adr.pdf

Low-Voltage High-Frequency Gated Ring Oscillator Using Bootstrap
Technique
http://www.el.gunma-u.ac.jp/~kobaweb/news/pdf/2012/AMDE2012_Kamiyama.pdf

High-resolution short time interval measurement system implemented
in a single FPGA chip
http://download.springer.com/static/pdf/727/art%253A10.1007%252Fs11434-011-4421-3.pdf?auth66=1418360984_e35e8a8588d3977c4d4d4d2109c1aaaa&ext=.pdf

Implementation of sub-nanosecond time-to-digital convertor in
field-programmable gate array
https://hal.archives-ouvertes.fr/in2p3-00873192/PDF/articleMST_Marteau-et-al_v1.pdf

New Jitter Measurement Technique Using TDC Principle in a FPGA
Component
http://www.inatel.br/biblioteca/component/docman/doc_download/3831-new-jitter-measurement-technique-using-tdc-principle

High Resolution Modular Time Interval Counter
http://ilrs.gsfc.nasa.gov/docs/timing/artyukh_time_interval_counter.pdf

Using Dynamic Reconfiguration to Implement High-Resolution
Programmable Delays on an FPGA
http://www.iro.umontreal.ca/~feeley/papers/BergeronFeeleyDaigneaultDavidNEWCAS08.pdf

A 2.6ps rms -Period-Jitter 900MHz All-Digital Fractional-N PLL Built
with Standard Cells
http://www-bsac.eecs.berkeley.edu/publications/search/send_publication_pdf2client.php?pubID=1307595132

C111 / P111 4 channel Time to Digital Converter User's manual
http://www.esrf.eu/files/live/sites/www/files/Instrumentation/DetectorsAndElectronics/Units/Electronics/digital-electronics-lab/c111.pdf

Carry-chain propagation delay impacts on resolution of FPGA-based TDC
http://www.j.sinap.ac.cn/nst/EN/article/downloadArticleFile.do?attachType=PDF&id=457

A 19.6 ps, FPGA-Based TDC With Multiple Channels for Open Source
Applications
http://ens.ewi.tudelft.nl/pubs/charbon12tcas_favi.pdf

A data driven high performance Time to Digital Converter
http://ph-collectif-lecc-workshops.web.cern.ch/ph-collectif-lecc-workshops/LEB00_Book/tracker/christiansen_track.pdf

On-Chip Timing Measurement Architecture with Femtosecond Resolution
http://eprints.soton.ac.uk/262543/1/collinsm_timemeasurement2.pdf

A 13b 315fs rms 2mW 500MS/s 1MHz Bandwidth Highly Digital
Time-to-Digital Converter Using Switched Ring Oscillators
http://www.cse.psu.edu/~xydong/files/proceedings/ISSCC2012/files/D27_04.pdf

A high resolution Time-to-Digital Converter on FPGA for
Time-Correlated Single Photon Counting
http://libgen.org/scimag/get.php?doi=10.1109/mwscas.2012.6292166

A Design of Vernier Coarse-Fine Time-to-Digital Converter using
Single Time Amplifier
http://ocean.kisti.re.kr/downfile/volume/ieek/E1STAN/2012/v12n4/E1STAN_2012_v12n4_411.pdf

All Digital Time-to-Digital Converter with High Resolution and Wide
Detect Range
http://www.engineeringletters.com/issues_v19/issue_3/EL_19_3_16.pdf

Examples of 1 PPS Clock Measuring Systems
http://www.wriley.com/Examples%20of%201%20PPS%20Clock%20Measuring%20Systems.pdf

On-Chip Processing for the Wave Union TDC Implemented in FPGA
http://lss.fnal.gov/archive/2009/conf/fermilab-conf-09-275-e.pdf

18-channel FPGA Wave Union TDC for Time-of-Flight Applications
http://lss.fnal.gov/archive/2009/conf/fermilab-conf-09-573-ppd.pdf

A 96-channel FPGA-based Time-to-Digital Converter (TDC)
http://www.phys.sinica.edu.tw/~e906/WWW_public/Doc/TDC/FPGA_TDC.pdf

Design of FPGA-based TDC for the ICAL Detector of India-based
Neutrino Observatory
http://www.hecr.tifr.res.in/~sudeshnadg/publication/FPGA_TDC.pdf

FPGA based Time-to-Digital Converter
http://www.sympnp.org/proceedings/56/G7.pdf

A Flash Time-to-Digital Converter with Two Independent Time Coding
Lines
IMEKO-IWADC-2011-12.pdf
http://www.imeko.org/publications/iwadc-2011/IMEKO-IWADC-2011-12.pdf

A 17ps Time-to-Digital Converter Implemented in 65nm FPGA Technology
http://infoscience.epfl.ch/record/139431/files/isfpga09-cfavi.pdf

A 12-Bit Vernier Ring Time-to-Digital Converter in 0.13 um CMOS Technology
http://www.eng.auburn.edu/~daifa01/Top/PubPapers/2010/Jpaper2010-02.pdf

A high-speed wide dynamic range time-to-digital converter
http://www.ssl.berkeley.edu/~mlampton/LamptonRaffanti.pdf

High Resolution Time-Interval Measurement Systems Applied To Flow
Measurement
http://www.metrology.pg.gda.pl/full/2014/M&MS_2014_077.pdf

Accurate time interval measurement electronics for pulsed time of
flight laser radar
http://www.ee.oulu.fi/~kari/Papers/Nantes1997.pdf

Signal Processing for Pico-second Resolution Timing Measurements
http://psec.uchicago.edu/Papers/NIM_v8b_final.pdf

High-Resolution Time-to-Digital Converter in Field Programmable Gate Array
http://cds.cern.ch/record/1158663/files/p383.pdf

Random Errors in Time Interval Measurement Based on SAW Filter Excitation
http://libgen.org/scimag/get.php?doi=10.1109/tim.2007.915465

A 96-channel, 500 ps resolution TDC board for the BaBar experiment at SLAC
http://www.ge.infn.it/babar/ITB/RT99/paper.pdf

A Cyclic Vernier TDC for ADPLLs Synthesized From a Standard Cell Library
http://wwweb.eecs.umich.edu/wics/publications/Park_TCASI2011.pdf

Nonlinearity Correction of the Integrated Time-to-Digital Converter
with Direct Coding
http://libgen.org/scimag/get.php?doi=10.1109/19.571882

PICTIC Interpolator Linearity
http://www.wriley.com/PICTIC%20Interpolator%20Linearity.pdf

Firmware-only Implementation of Time-to-Digital Converter (TDC) in
Field-Programmable Gate Array (FPGA)
http://www-ppd.fnal.gov/EEDOffice-W/Projects/ckm/comadc/PID26522.pdf

High-Precise Portable Time Interval and Frequency Counter
http://tycho.usno.navy.mil/ptti/2012papers/PTTI2012.p247.pdf

FPGA-based time counters with a wander measurement mode
http://www.pwt.et.put.poznan.pl/PWT_2012/PWT%202012_2242.pdf

The Simple PICTIC
http://www.ko4bb.com/dokuwiki/lib/exe/fetch.php?id=precision_timing%3Apictic&cache=cache&media=precision_timing:simple_pictic.pdf

A Saw-tooth Wave Based Design of Time to Digital Converter
http://www.wseas.us/e-library/conferences/2009/budapest/SMO/SMO68.pdf

A Multi-Path Gated Ring Oscillator TDC With First-Order Noise Shaping
http://www.cppsim.org/Publications/JNL/straayer_jssc09.pdf

Micrel LVPECL, CML 5GHz - 7GHz Buffer
http://www.micrel.com/_PDF/Eval-Board/sy58011-12-13u_eb.pdf

Micrel LVPECL, CML 4GbpS - 10.7Gbps Multiplexer
http://www.micrel.com/_PDF/Eval-Board/sy58017-18-19u_eb.pdf

A flash high-precision Time-to-Digital Converter implemented in FPGA
technology
http://indico.cern.ch/event/49682/session/35/contribution/3/material/slides/0.ppt

FPGA-Based High Area Efficient Time-To-Digital IP Design
http://www.ifm.umich.mx/~villasen/TESIS/Mario/TDC.pdf

Firmware-only Implementation of Time-to-Digital Converter (TDC) in FPGA
http://www-ppd.fnal.gov/EEDOffice-W/Projects/ckm/comadc/tdc1s.pdf

A Time-To-Digital Converter (TDC)
https://indico.phys.hawaii.edu/getFile.py/access?contribId=4&resId=0&materialId=slides&confId=392

96-Channel FPGA-Based Time-To-Digital Converter
http://hep.uchicago.edu/~frisch/TDC_NIM_v12.pdf

Texas Instruments THS788 Quad-Channel Time Measurement Unit (TMU)
http://www.ti.com/lit/ds/symlink/ths788.pdf

A 128-channel Time-to-Digital Converter (TDC) inside a Virtex-5 FPGA
on the GANDALF module
http://wwwhad.physik.uni-freiburg.de/gandalf/modules/download_gallery/dl.php?file=59

Vernier's Delay Line Time-to-Digital Converter
http://www.np.ac.rs/yu/preuzimanjasve/publications/vol1br1/181-verniers-delay-line-time-to-digital-converter/download

Time-to-Digit Converter Based on Radiation-Tolerant FPGA
- Interesting calibration analysis
http://kmlinux.fjfi.cvut.cz/~vacekmic/docs/vzlu_tdc.pdf

A High-Resolution Time-to-Digital Converter Implemented in
Field-Programmable-Gate-Arrays
http://mi.sibet.cas.cn/zlgx/201310/W020131024537685817071.pdf

Picosecond Resolution Time-to-Digital Converter Using G m -C
Integrator and SAR-ADC
http://www.ssc.pe.titech.ac.jp/publications/2014/IEEE_trans/xu/Xu_GmTDC_Journal_Final_V5.pdf

A Design of Vernier Coarse-Fine Time-to-Digital Converter using
Single Time Amplifier
http://www.jsts.org/html/journal/journal_files/2012/12/Year2012Volume12_04_05.pdf

Patents

Burbeck METHOD AND APPARATUS FOR AUTOMATICALLY MEASURING TIME
INTERVALS
https://patentimages.storage.googleapis.com/pdfs/US2665410.pdf

Frady DOUBLE INTERPOLATION METHOD AND APPARATUS FOR MEASURING TIME
INTERVALS
https://patentimages.storage.googleapis.com/pdfs/US2665411.pdf

Bagley ELECTRONIC INTERPOLATING COUNTER FQR THE TIME INTERVAL AND
FREQUENCY MEASUREMENT
https://patentimages.storage.googleapis.com/pdfs/US3133189.pdf

Nutt DIGITAL INTERVALOMETER
https://patentimages.storage.googleapis.com/pdfs/US3983481.pdf

Janowitz TIME INTERVAL MEASUREMENT METHOD AND APPARATUS
https://patentimages.storage.googleapis.com/pdfs/US3999128.pdf

Thornton HIGH RESOLUTION DATA ACQUISITION
http://patentimages.storage.googleapis.com/pdfs/US5200933.pdf

Condreva HIGH RESOLUTION TIME INTERVAL COUNTER
https://patentimages.storage.googleapis.com/pdfs/US5333162.pdf

Kattan TIME INTERVAL ANALYZER HAVING MULTIPLE MEASUREMENT CIRCUITS
http://patentimages.storage.googleapis.com/pdfs/US6226231.pdf

Nair CORRECTION FOR PIPELINED ANALOG TO DIGITAL (A/D) CONVERTER
http://patentimages.storage.googleapis.com/pdfs/US6784814.pdf

Gao HIGH RESOLUTION SAMPLING-BASED TIME TO DIGITAL CONVERTER
http://patentimages.storage.googleapis.com/pdfs/US8564471.pdf

Thesis

An Integrated Cmos High Precision Time-To-Digital Converter Based On
Stabilised Three-Stage Delay Line Interpolation
- Excellent review
http://herkules.oulu.fi/isbn951427461X/isbn951427461X.pdf

Multi-Path Differential Delay Line based Time-to-Digital Converter
for ADPLL
http://www.diva-portal.org/smash/get/diva2:635168/FULLTEXT01.pdf

Noise Shaping Techniques for Analog and Time to Digital Converters
Using Voltage Controlled Oscillators
http://cppsim.org/Publications/Theses/straayer_phdthesis.pdf

Implementation of the high resolution high dynamic Time to Digital
Converter
https://www.politesi.polimi.it/bitstream/10589/92658/1/Thesis_V1.0.2_Build04031059.pdf

A Stabilized Multi- Channel Cmos Time-To- Digital Converter Based On
A Low Frequency Reference
http://herkules.oulu.fi/isbn9789514299322/isbn9789514299322.pdf