qutools quTAG MC User manual

quTAG MC
Time-to-Digital Converter
Manual V1.0

2 quTAG MC Manual www.qutools.com
Contents
1. Introduction.................................................................................................................... 4
1.1 quTAG MC –state of the art time-to-digital converter............................................... 4
1.2 Technical overview................................................................................................... 4
1.3 Jitter Measurement.................................................................................................. 5
2. Safety and Maintenance.................................................................................................. 6
2.1 Legend..................................................................................................................... 6
2.2 General Instructions................................................................................................. 6
2.3Environmental Conditions........................................................................................ 7
2.4 Electrical Installation................................................................................................ 7
2.5 Preventive Maintenance........................................................................................... 7
2.6 Safety Testing .......................................................................................................... 8
2.7 Cleaning .................................................................................................................. 8
3Technical Specifications .................................................................................................. 9
4Variants and Options......................................................................................................11
5Hardware Description ....................................................................................................12
5.1 Front side................................................................................................................12
5.2 Displays on the front panel......................................................................................13
5.3 Rear side .................................................................................................................13
5.4 Marker Inputs .........................................................................................................14
5.5 Output Channels.....................................................................................................15
5.6 Synchronization ......................................................................................................16
5.7 First Setup ..............................................................................................................16
6Software Installation and Configuration .........................................................................17
6.1 Software Installation...............................................................................................17
6.2 Firmware Update ....................................................................................................18
6.3 Hardware ID ...........................................................................................................19
6.4 Option Upgrade ......................................................................................................20
7Daisy Software...............................................................................................................21
7.1 Counting ................................................................................................................21
7.2 Coincidences...........................................................................................................23
7.3 Histograms.............................................................................................................24
7.4 Correlation Measurement: HBT ...............................................................................25
7.5 Lifetime Measurement............................................................................................27
7.6 Detector Parameter Settings ...................................................................................28
7.7 Filters .....................................................................................................................30
8Other Software Components..........................................................................................32
8.1 quTAG custom software ("DLL") ...............................................................................32
8.2 Tarec ......................................................................................................................32
8.3 Command Line Interface .........................................................................................33
9FAQ / Trouble Shooting ..................................................................................................34
9.1 USB Driver Version ..................................................................................................34
9.2 Firmware Version....................................................................................................34

www.qutools.com quTAG MC Manual 3
9.3 Unexpected Delays .................................................................................................34
9.4 Low Resolution........................................................................................................35
10 Revision History..........................................................................................................36

4 quTAG MC Manual www.qutools.com
1. Introduction
1.1 quTAG MC –state of the art time-to-digital converter
The quTAG MC –Multi Channel –is a time-to-digital converter that measures electric signals
and marks them with time tags. This stream of time tags can be used in various and versatile
applications –from measurements in the picosecond range up to an hour.
The universal time tagging method allows correlation measurements (cross-correlation, auto-
correlation), lifetime measurements (start-(multi)stop) and many more possibilities within one
measurement. The saved stream of time tags contains all information needed to reconstruct
every measurement and analysis performed.
1.2 Technical overview
The key features of the quTAG device are:
•High timing resolution (bin size 1 ps)
•High event rates
•USB3.0 interface
•Easy-to-use
The device can be used for a variety of Applications:
•Time correlated single photon counting (TCSPC)
•Fluorescence lifetime imaging
•Quantum information experiments
•LIDAR

www.qutools.com quTAG MC Manual 5
•High energy/accelerator physics
•High precision time measurements
Channels input
1 Start / 8, 16, 32 Stop
Bin width
1 ps
Timing jitter –RMS, FWHM
20 ps, 50 ps
Input pulse high level
-5.0 V ... + 3.5 V
Input Impedance
50 Ohm
1.3 Jitter Measurement
In order to measure the jitter, we generate an electrical pulse with steep edges. This pulse gets
split into two by a power splitter and sent into two different inputs of the quTAG (i.e. start and
stop-X or stop-X and stop-Y). Then we use the quTAG software to generate a start-stop-
histogram.
We fit a Gaussian function to this histogram and determine RMS and FWHM. The single
channel jitter corresponds to σ/ √2 from this two-channel measurement, assuming equal
Gaussian contributions from both signals. The FWHM can be obtained by the standard
deviation with the relation FWHM = 2 √2 ln 2 σ≈2.35 σ.

6 quTAG MC Manual www.qutools.com
2. Safety and Maintenance
2.1 Legend
Caution
General risk of danger.
Warning
An instruction which draws attention to the
risk of injury or death.
Warning
Risk of electric shock. High voltages present.
2.2 General Instructions
The equipment, as described herein, is designed for use by personnel
properly trained in the use and handling of mains powered electrical
equipment. Only personnel trained in the servicing and maintenance of this
equipment should remove its covers or attempt any repairs or adjustments.
If malfunction is suspected, immediately return the part to the vendor for
repair or replacement. There are no user-serviceable parts inside the
electronics. Modified or opened electronics cannot be covered by the
warranty anymore. Take special care if connecting products from other
manufacturers. Follow the General Accident Prevention Rules.
If this equipment is used in a manner not specified by the manufacturer,
the protection provided by the equipment may be impaired. Do not operate
the instrument outside its rated supply voltages or environmental range. In
particular, excessive moisture may impair safety.
For laboratory use only. This unit is intended for operation from a normal,
single phase supply, in the temperature range 5° to 40°C, 20%to 80%RH.

www.qutools.com quTAG MC Manual 7
2.3 Environmental Conditions
Warning. Operation outside the following environmental limits may
adversely affect operator safety:
•Indoor use only
•Maximum altitude 2000 m
•Temperature range 5°C to 40°C
•Maximum humidity less than 80%RH (non-condensing) at 31°C
•To ensure reliable operation the unit should not be exposed to
corrosive agents or excessive moisture, heat or dust. If the unit has
been stored at a low temperature or in an environment of high
humidity, it must be allowed to reach ambient conditions before
being powered up.
2.4 Electrical Installation
The unit must be connected only to an earthed fused supply of 100 to 240V
(Japan, USA and Europe).
Use only power supply cables supplied by the manufacturer, other cables
may not be rated to the same current. The unit is shipped with appropriate
power cables for use in Europe. When shipped to other territories the
appropriate power plug must be fitted by the user.
Never connect any cabling to the electronics when contacts are exposed!
Avoid short-cuts.
Prevent electrical shock from electronic. To prevent electrical shock do not
remove the cover of the control unit. Unplug power cord and all other
electrical connections and consult qualified service personnel when
servicing or cleaning. Operate only under dry conditions and at room
temperature conditions.
2.5 Preventive Maintenance
The equipment contains no user serviceable parts. There is a risk of severe
electrical shock if the equipment is operated with the covers removed. Only
personnel authorized by the vendor and trained in the maintenance of this
equipment should remove its covers or attempt any repairs or adjustments.
Maintenance is limited to safety testing and cleaning as described in the
following sections.

8 quTAG MC Manual www.qutools.com
2.6 Safety Testing
Safety testing in accordance with local regulations, should be performed on
a regular basis, (typically once per year for an instrument in daily use).
Caution. The instrument contains a power supply filter. Insulation testing
of the power supply connector should be performed using a DC voltage.
2.7 Cleaning
Disconnect the power supply before cleaning the unit. Never attempt to
clean the quTAG by immersion into any liquid. Never allow water to get
inside the case. The quTAG parts are sensitive to any kind of liquid. Do not
use any type of abrasive pad, scouring powder, or solvent, e.g. alcohol or
benzene. Please note that all parts of quTAG are cleaned in our production
facility.

www.qutools.com quTAG MC Manual 9
3 Technical Specifications
Time to digital converters
Digital resolution
1 ps
Timing jitter –RMS, FWHM
20 ps, 50 ps
Max. event rate per channel
100 Mcps
Sustained throughput rate
100 Mcps (USB3.0)
Delay range
-50 … +50 ns
Delay resolution
1 ps
Min. pulse to pulse separation
10 ns
Differential non-linearity
<1%
Max. acquisition time without overflow
1.25 h
Input Channels
Number of channels
1 start / 8, 16, 32 stop
Connector
SMA
Signal level range
-5.0 V … + 3.5 V, e.g. LVTTL, NIM
Offset voltage max.
± 10 mV
Min. input level
± 50 mV
Threshold level resolution
0.15 mV
Threshold voltage range
- 3.0 V…+ 3.0 V
Threshold voltage offset max.
± 25 mV
Edge
Rising, falling
Min. input pulse width
1 ns
Termination
50 Ohm
Output Channels
Number of channels
2
Connector
D-Sub, Pins 3 & 1
Signal levels
LVTTL
Delay range
-100… 100 ns
Delay resolution
10 ps
Impedance
50 Ohm

10 quTAG MC Manual www.qutools.com
Clock Input
Frequency
1 –100 MHz
Signal levels (threshold)
-5 V … +5 V
Signal form
Sinusoidal, square wave
Termination
50 Ohms
Input connector
SMA
Marker Inputs
Marker Inputs
4
Input pulse width minimum
10 ns
Input pulse level
Low -0.5 … 0.8 V
High 2.0 … 5.5 V
Input Impedance
470 Ohm
Digital resolution
5 ns
Timing Jitter
2 –5 ns
Connector
D-Sub, Pins 7, 6, 20, 19
Sync Output
Signal type
Square wave
Frequency
10 MHz
Signal level
LVTTL
Output impedance
50 Ohms
Connector
SMA
Operation
Interface
USB3.0
Operating system
Windows, Linux
Power consumption
< 50W at 100 to 230 VAC, 50-60 Hz

www.qutools.com quTAG MC Manual 11
4 Variants and Options
The quTAG MC can be upgraded with the following features. The optional features that can also
be installed individually. The basic variant does not include any of the options listed below. For
the procedure of installation refer to section 6.4 .
Option
Meaning
Cross-correlation
Enables correlation measurement software, see section 7.4 for details.
Lifetime
Enables lifetime measurement software, see section 7.5 for details.
Markers
4 GPIO-Inputs can be used as data markers. The markers are included in
the timeline to help sorting timestamps. See sections 5.4 and 7.6 .
Device
Synchronization
Devices can be synchronized by the Sync-Out SMA connector via 10 MHz.
If an external clock is connected, the Sync-Out signal is phase locked to the
input.
External Clock
The device may be synchronized to an external clock signal 10 MHz.
User defined
External Clock
The external clock frequency can be changed from 1 –100 MHz.
Filters
Filters timestamp events that are not needed for the application. This
filtering happens inside the device and therefore saves bandwidth on the
USB connection. See section 7.7 for more details.
Channel Output
The two programmable outputs enable conditional measurements, state
preparation, gating of detectors, control of shutters and more to
synchronize events. An adjustable delay can be added on the output signal
by software.

12 quTAG MC Manual www.qutools.com
5 Hardware Description
5.1 Front side
The quTAG MC comes in different variants with 8, 16 or 32 stop input channels.
Figure 1: Front side of the quTAG MC - 8 stop input channels
Figure 2: Front side of the quTAG MC - 16, 32 stop input channels
1
SMA start input connector
2
SMA clock input connector
3
One of 8 or 16 SMA stop input connectors on the front side,
see rear side 5.3 for channels 17-32
4
Start channel display
5
Menu display for options, see detailed description 5.2
•Switching the stop input channels to the SMA stop input connectors of the rear
side, only at 32 channel devices
•showing information about markers on the front displays
•switching the displays off/on

www.qutools.com quTAG MC Manual 13
5.2 Displays on the front panel
Single tap on the left display to toggle on and off the
illumination of all displays within the device.
Channel mode (start/stop) and channel number.
Displaying the counts per second.
Threshold with rising / falling edge. The threshold level
is displayed next to it.
External Clock connected / Clock not connected
Filter (see section 7.7 for details) active on that channel
5.3 Rear side
Figure 3: Rear side of the quTAG MC 32 channels
Make sure the cooling fans are not obstructed.
Otherwise, the quTAG may be damaged due to overheating.
1
LAN port
2
USB3.0 connection
3
Service port
4
GPIO port: marker inputs, channel outputs and general purpose IOs
5
Synchronization output
6
WIFI antenna

14 quTAG MC Manual www.qutools.com
7
Stop input channels 17-32, device dependent
8
AC power input and power switch
5.4 Marker Inputs
In addition to the channel inputs, the device features marker inputs that insert marker
timestamps in the timeline. They can be connected e.g., to some pixel clock or line clock in order
to help sorting the timestamps. The GPIO Connector is used for those inputs:
Figure 4: D-Sub connector at the back panel
Marker inputs 1...4 reside on pins 7, 6, 20, 19. Use the additionally shipped breakout cable.
If configured by software, Marker events are saved within the data stream as timestamps.
Channel numbers 100-103 are the Markers 1-4 with rising edge and 105-108 with falling edge.

www.qutools.com quTAG MC Manual 15
Marker Inputs
4
Input pulse width min.
10 ns
Input pulse level
Low -0.5 … 0.8 V
High 2.0 … 5.5 V
Input Impedance
470 Ohm
Digital resolution
5 ns
Timing Jitter
2 –5 ns
5.5 Output Channels
In addition to the channel inputs, the device features 2 output channels. The two programmable
outputs enable conditional measurements, state preparation, gating of detectors, control of
shutters and more to synchronize events. An adjustable delay can be added on the output signal
by software. The GPIO Connector is used for those outputs:
Figure 5: D-Sub connector at the back panel
The output channels 1 and 2 reside on pins 3 and 1. Use the additionally shipped breakout cable.

16 quTAG MC Manual www.qutools.com
5.6 Synchronization
Multiple quTAGs can be synchronized –provided the "Sync" option (see section 4 ) is activated.
To synchronize devices, connect the Sync-Out from your master device to the clock input of the
next quTAG. The Sync-Out synchronizes the internal clock via 10 MHz of both devices. Additional
devices can be connected by the same principle.
Multiple instances of Daisy can be run to work with different synchronized devices. The usage of
multiple devices by the DLL is described in a Python software example.
5.7 First Setup
•Install the USB driver included in the software package,
downloaded from the homepage.
•Supply power to the quTAG via the AC power input and turn it on using the power
switch.
•Connect the quTAG to a PC using the USB 3.0 connector. An USB 2.0 can be used, but
limits the transfer rate.
•The clock input hasn't to be connected in most cases. It is used only to synchronize the
device with an external clock source.
•"Payload" signals are connected to the start and the stop input connectors, see input
channel specifications.
Output channels
2
Connector
D-Sub, Pin 3 and 1
Signal levels
LVTTL
Delay range
-100… 100 ns
Delay resolution
10 ps
Impedance
50 Ohm

www.qutools.com quTAG MC Manual 17
6 Software Installation and Configuration
6.1 Software Installation
The quTAG software can be installed on Windows 7, 8, 8.1, and 10, 32- and 64 Bit. The Linux
version requires a x86-64 Bit distribution with libc 2.19 or newer.
On Windows, using the
installer
Daisy@QUTAG-MC-
V x.y.z .exe
Start the installer program and follow the instructions. Drivers
and necessary libraries will be installed automatically.
On Windows, using the
zip archive QUTAG-MC-
V x.y.z .zip
Extract the zip archive to a directory of your choice.
Install the device driver in the usbdriver directory using
dpinst32.exe or dpinst64.exe, whatever conforms to your
Windows version.
On Linux, using the
tgz archive QUTAG-MC-
V x.y.z .tgz
1. The software is built for x86 systems; builds for 32 bit and 64
bit (AMD architecture) systems are available. It is linked
against libc 2.19; binary compatibility has been verified with
different distributions / distribution families.
2. Besides the standard installation, the following software is
required:
a) Qt4 Core, GUI, and OpenGL libraries
(Ubuntu: packets libqtcore4, libqtgui4 libqt4-opengl:
e.g. add the repository:
sudo add-apt-repository ppa:rock-core/qt4)
b) libusb 1.0 (don't confuse with libusb 0.1)
(Ubuntu: libusb-1.0-0)
3. Extract the directory tree to a place of your choice. E.g.
/home/me/daisy .
4. Add nhands.rules from /home/me/daisy/install to the udev
rules. (Ubuntu: copy to /etc/udev/rules.d, requires root
privileges).
The file installs a rule that grants access to nhands USB
devices to every user.
5. Daisy et al. require a couple of shared libraries that reside in
the program folder. The program loader must be enabled to
find those libs. Using the start scripts "rundaisy" and
"runflasher" instead of "daisy" and "nhflash" will do the job.
To call the programs (or userlib applications) directly, the
library path has to be published. This may be achieved
a) temporarily: add the extra search path to your shell:
export
LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/home/me/daisy

18 quTAG MC Manual www.qutools.com
Daisy only can be started by command from that shell
window:
/home/me/daisy/daisy &
b) permanently: add the extra search path to the loader
config. Ubuntu: create a file "daisy.conf" that contains just
one line /home/me/daisy .
Copy that file to /etc/ld.so.conf.d and call ldconfig for cache
generation. Root privileges required.
Daisy now can be started by command or file manager click.
Note that daisy versions can't be installed in parallel this way
because daisy's shared libs don't have real version
management.
The following software is packed in the zip/tgz archive:
daisy
"Data Analysis and Imaging System" –the main control software
for the quTAG. See chapter 7 .
nhflash
The firmware update tool. See section 6.2 .
tarec
A record & merge tool for synchronized devices. See section 8.1 .
tdccli
A command line tool for simple tasks. See section 8.3 .
userlib
The directory contains the custom programming library, with
HTML documentation and LabView wrapper VIs. See section 8.1 .
usbdriver
USB driver packet for Windows 32 and 64 Bit.
firmware
Firmware for the device.
When using the Windows installer, also start menu entries for the programs are created.
6.2 Firmware Update
Attention: Naturally, firmware updates are a delicate process and can
potentially harm the device if done incorrectly. Please read and follow the
instructions carefully.
A firmware update is generally necessary when a new software version is installed. If the control
software is warning about an outdated firmware or if you are unsure if the firmware currently
running is up to date, execute the following procedure:
1. Turn on the device. If any quTAG software is still running, close it.

www.qutools.com quTAG MC Manual 19
2. Start nhflash(.exe). After some time, the indicator turns green. Proceed only if the tool
display "Firmware: outdated".
3. Press "Flash". Make absolutely sure the device is not shut down or disconnected during
this step! The flash process takes several minutes and may seem to hang without
progress for up to 3 minutes. After the update is completed successfully, the indicator
stops flashing and the text next to it shows "Update complete".
4. Close the firmware update utility.
5. Turn the quTAG device off and on again.
Figure 6: The firmware update tool nhflash
6.3 Hardware ID
The Hardware ID is a (positive) number stored in the device so that it can be used to distinguish
between multiple quTAG that are connected to the same PC. If the Daisy software detects more
than one device, it asks the user to select a device using the Hardware IDs and serial numbers.
Also, the DLL uses the ID to identify a device. If device discrimination is an issue, individual IDs
should be programmed.
To assign a device ID start Daisy.exe, locate "id.ngc" in the installation folder with the file manager
and drag it into the program window (or open the program menu using ctrl+F9 and select file/
load panel). Enter an individual ID and press "Save". Close the program window and restart the
device.
Figure 7: Programming the Hardware ID

20 quTAG MC Manual www.qutools.com
6.4 Option Upgrade
As stated in chapter 4 the number of axes and some features of quTAG are optional. Options and
axes may be upgraded (or downgraded) on-site by entering a device specific key. The serial
number of the quTAG is required when ordering an upgrade key.
To inspect the active options or to install a new one start Daisy. In the file manager, locate
"feature.ngc" in the installation folder and drag it into the program window (or open the program
menu using ctrl+F9 and select file/load panel). Enter the key obtained from the vendor and press
Enter. Close the program window and restart the device.
Figure 8: Option upgrade