Anfatec AMU2.4 User manual

PCI-BUS LOCKIN AMPLIFIER 1 Hz TO 1 MHz
Anfatec Instruments AG
Melanchthonstr. 28
08606 Oelsnitz /V.
Germany
Tel.: [phone]
Fax.: [phone]
http://www.anfatec.de
email: [email protected]
Manual Anfatec PCI-Lockin Amplifier AMU2.4 – Rev. 1.10 dated 30/09/20 Page 1 (70)

Table of contents
1 General Information .............................................................................................................. 6
1.1 Specification of the AMU2.4-LIA ..................................................................................... 6
1.1.1 Signal Input ........................................................................................................................ 6
1.1.2 Reference Output ............................................................................................................... 6
1.1.3 PLL .................................................................................................................................... 6
1.1.4 General .............................................................................................................................. 7
1.2 Licence for the software ................................................................................................ 7
2 Get started ........................................................................................................................... 8
2.1 System requirements ..................................................................................................... 8
2.2 Software installation ...................................................................................................... 8
2.3 Card and Driver installation ............................................................................................ 8
2.3.1 Check your APIC configuration ............................................................................................. 8
2.3.2 Card Installation ................................................................................................................. 8
2.3.3 Driver Installation .............................................................................................................. 9
2.4 Connections to the card ................................................................................................. 9
2.5 APIC configuration ....................................................................................................... 10
3 LockIn Amplification Basics ................................................................................................... 11
3.1 The general idea of Lockin Amplification -> LockIn ........................................................ 11
3.2 Mathematical description ............................................................................................. 12
3.3 Time constant Definition .............................................................................................. 13
3.4 RollOff Definition ........................................................................................................ 13
3.5 Noise Measurements ................................................................................................... 14
4 Software Description (Lockin.exe) .......................................................................................... 15
4.1 Overview .................................................................................................................... 15
4.2 Functions in the Menu Line .......................................................................................... 16
4.2.1 File ................................................................................................................................... 16
4.2.2 Option .............................................................................................................................. 16
4.2.3 View ................................................................................................................................. 16
4.2.4 Help ................................................................................................................................. 16
4.3 Functions in the Function Line ...................................................................................... 16
4.3.1 Frequency Sweep .............................................................................................................. 16
4.3.2 Oscilloscope ...................................................................................................................... 16
4.4 Parameter settings ....................................................................................................... 18
4.4.1 Time constant ................................................................................................................... 18
4.4.2 RollOff .............................................................................................................................. 18
4.4.3 Dynamic ........................................................................................................................... 18
4.4.4 Coupling ........................................................................................................................... 18
Manual Anfatec PCI-Lockin Amplifier AMU2.4 – Rev. 1.10 dated 30/09/20 Page 2 (70)

4.4.5 The Meters ....................................................................................................................... 18
4.4.6 Frequency ........................................................................................................................ 19
4.4.7 Amplitude ......................................................................................................................... 19
4.4.8 Phase ............................................................................................................................... 19
4.4.9 Harmonic .......................................................................................................................... 19
4.5 Sweep Frequency ........................................................................................................ 19
4.5.1 Window Description .......................................................................................................... 19
4.5.2 Options for the frequency sweep ........................................................................................ 20
5 Examples ............................................................................................................................ 23
5.1 Demonstrate time constant .......................................................................................... 23
5.2 Demonstrate RollOff .................................................................................................... 24
5.3 Resonance Detection ................................................................................................... 25
5.4 Thermal noise ............................................................................................................. 26
5.4.1 Simulation of the noise voltage in qucs ............................................................................... 26
5.4.2 Noise Voltage Detection ..................................................................................................... 27
Calculation of the noise voltage ............................................................................... 28
5.5 Fourieranalyse of a square signal .................................................................................. 29
5.6 Acoustic resonance ...................................................................................................... 30
6 DLL Description .................................................................................................................... 33
6.1 Working with the DLL in C projects .......................................................................... 33
6.2 DLL-Functions ............................................................................................................. 34
6.3 Example programs ....................................................................................................... 37
7 Remote Control with LabView ................................................................................................ 38
7.1 Files and Locations ...................................................................................................... 38
7.2 General Programming Directions in LabView .................................................................. 39
7.3 Description of Example VI Files .................................................................................... 40
Example Time Constant .......................................................................................... 42
Example Fourier Analysis of a square signal ............................................................. 42
7.4 Multiple LockIn Amplifiers in LabView ............................................................................ 48
8 Remote Control in Python 3 .................................................................................................. 49
8.1 Files and Locations ...................................................................................................... 49
8.2 Call DLL Functions in Python ........................................................................................ 49
8.3 Multiple Devices in Python ........................................................................................... 49
8.4 Python Example Files ................................................................................................... 50
8.4.1 Spectrum Analyzer ............................................................................................................ 50
Simple Frequency sweep ....................................................................................... 51
Example FourierAnalyse .......................................................................................... 51
8.4.2 Transient Recorder ............................................................................................................ 52
8.4.3 Network Analyzer .............................................................................................................. 52
Manual Anfatec PCI-Lockin Amplifier AMU2.4 – Rev. 1.10 dated 30/09/20 Page 3 (70)

Example Measurement Resonance ........................................................................... 52
Example Acoustic Resonance .................................................................................. 53
8.4.4 Parametric Sweep (Only USBLockin) ................................................................................... 55
Example Diode AUX ................................................................................................ 55
8.4.5 Multiple Devices ................................................................................................................ 57
8.4.6 Experiment: Distance Measurement .................................................................................. 58
9 Remote Control in Scilab ....................................................................................................... 59
9.1 Files and Locations ...................................................................................................... 59
9.2 Call DLL Functions in Scilab .......................................................................................... 59
9.3 Scilab Example Files .................................................................................................... 59
9.3.1 Spectrum Analyzer ............................................................................................................ 59
9.3.2 Transient Recorder ............................................................................................................ 60
9.3.3 Networkanalyzer ............................................................................................................... 60
9.3.4 Parametric Sweep (Only USBLockin) ................................................................................... 61
10 Example: Electrical Force Microscope ................................................................................... 62
11 Revision History .................................................................................................................. 64
11.1 Manual-related Revisions ............................................................................................ 64
11.1.1 Till 19th June 2007 .......................................................................................................... 64
11.1.2 10th April 2008 .............................................................................................................. 64
11.1.3 10th Frebruary 2009 ...................................................................................................... 64
11.2 Hardware Revisions ................................................................................................... 64
11.2.1 1st November 2006 – Rev 2.2 to Rev 2.3 ......................................................................... 64
11.2.2 1st December 2006 – Rev 2.3 to Rev 2.3a ....................................................................... 65
11.2.3 14th April 2007 – Rev. 2.3a to Rev 2.4 ............................................................................ 65
11.2.4 10th April 2008 – Rev 2.4 ................................................................................................ 65
11.3 Software Revisions ..................................................................................................... 65
11.3.1 10th April 2008 – Version 1.02 ......................................................................................... 65
11.3.2 11th May 2009 – Version 1.04 ......................................................................................... 65
11.3.3 11th July 2009 – Version 1.05 .......................................................................................... 65
11.3.4 26th August 2009 – Version 1.06 ..................................................................................... 66
11.3.5 May 2013 ...................................................................................................................... 66
11.4 Driver Revisions ......................................................................................................... 66
11.4.1 November 2013 ............................................................................................................. 66
12 Troubleshooting .................................................................................................................. 66
12.1 Device driver ............................................................................................................. 66
12.2 Application ................................................................................................................ 69
12.2.1 App ................................................................................................................................ 69
12.2.2 DLL ............................................................................................................................... 69
Manual Anfatec PCI-Lockin Amplifier AMU2.4 – Rev. 1.10 dated 30/09/20 Page 4 (70)

Copyright 2002-2020 Anfatec Instruments AG. All rights reserved. Anfatec is a registered
trademarks of Anfatec Instruments AG. Other product and brand names may be trademarks or
registered trademarks of their respective owners. Anfatec Instruments AG assumes no
responsibility for any damage or loss resulting from use of this manual. Anfatec Instruments AG
assumes no responsibility for any damage or loss resulting from use of the software. Anfatec
Instruments AG assumes no responsibility for any damage or loss by deletion of data as a result of
malfunction, dead battery, or repairs. Be sure to make backup copies of all important data on
other media to protect against data loss. Important: Please read Anfatec Licence Agreement
contained in this handbook before using the accompanying software programs. Using any part of
the software indicates that you accept the terms of Anfatec Software Licence Agreement.
Manual Anfatec PCI-Lockin Amplifier AMU2.4 – Rev. 1.10 dated 30/09/20 Page 5 (70)

1
1 ENERAL INFORMATION ENERAL INFORMATION
1.1 SPECIFICATION OF THE AMU2.4-LIA
eneral
Digital Quad(1)-Phase Lock-In Amplifier
Dynamic Reserve > 135 dB (1)
Noise < 6 nVrms/Hz0.5 @100kHz (1)
Time Constants 0.1 ms ... 1 ks (1)
Sensitivity 10 nV ... 10 V
Phase Resolution 0.001°
1.1.1 SI NAL INPUT
Voltage Input single-ended SMB
Input coupling: dc or ac (f3dB = 2 Hz)
Input Impedance 100 k || 20 pF (1) / 1 M on requ.
Damage Threshold /- 12 V
Bandwidth dc to 1 MHz (f3dB > 1 MHz)
Input Ranges ± 5 V, ± 500 mV, ± 50 mV (1)
Input Sensitivity 10 nV to 10 V
Typical Input Noise: Uac = 0 V, 50 W @ input
@ 100 kHz, high dynamic < 300 nVrms/Hz0.5
@ 100 kHz, normal dynamic < 50 nVrms/Hz0.5
@ 100 kHz, low dynamic < 8 nVrms/Hz0.5
RollOff 6 dB/oct, 12 dB/oct, 24 dB/oct
Time Constants 0,2 ms ... 5 s
Gain deviations between dynamic ranges: < 5%
1.1.2 REFERENCE OUTPUT
Internal Oscillator 10 mHz .. > 1 MHz
Frequency Resolution < 10 mHz
Frequency Accuracy /- 50 ppm from 0 °C to 70 °C
Reference Output Voltage < 1 mVpp ... 15 Vpp
Output Noise Uac = 1 mV
@ 100 kHz < 200 nVrms/Hz0.5
1.1.3 PLL
Frequency range 1 Hz .. 1 MHz
Locking time < (100 ms 10 Cycle)
Phase error < 4 deg @ f < 1 kHz
Input amplitude TTL
Phase delay ~ 1 µs
(1)See Revision History on Page 27
Manual Anfatec PCI-Lockin Amplifier AMU2.4 – Rev. 1.10 dated 30/09/20 Page 6 (70)

1.1.4 ENERAL
Interface Plug & Play PCI-Bus 2.4 interface
Drivers Windows NT/2000, Windows XP,
Windows 7 & Windows 10 - both 32 bit & 64 bit
Interrupt rate 40 kHz
Warranty 2 years
1.2 LICENCE FOR THE SOFTWARE
The LockIn software is provided with the General Public Licence (GPL). This licence has been
developed within a project of the "Free Software Foundation". It gives the user the liberty, to add
changes in the code and the programmer the security, not to get in trouble due to the users
changes.
Most commercial software packages don't use this licence, because they want to keep the right to
sell the newer version later as update. An open software can be changed by the user. So, he can
adapt the software to his problem. Free software, has to stay free, even if the user add some
changes. Therefore, GPL protects the software so, that all programs which are based on a GPL
protected source code has to provided with the same GPL again. The licence also hinders software
patenting.
Manual Anfatec PCI-Lockin Amplifier AMU2.4 – Rev. 1.10 dated 30/09/20 Page 7 (70)

2
2 ET ET START STARTED ED
2.1 SYSTEM REQUIREMENTS
–compatible PC
–free PCI slot
–APIC installed (recommended) - for details see here
–1 MB hard disk space
–Windows NT 4.0 / Windows 2000 or Windows XP / Windows 7
2.2 SOFTWARE INSTALLATION
There are two ways for installation:
automatic. Start the setup.exe in the root directory of the installation CD.
Manual: Before installing the driver, install the software. Put the installation disk named “Software
for the AMU2.4” in the disk drive and and copy at least the four needed files
lockin.exe, lockin.ini, lockin.sys and lockin.inf
into a new directory, for instance: C:\Programme\Anfatec\LockIn . On the installation CD, you find
these files under the directories: /bin (*.exe, *.ini) and /driver (*.sys, *.inf).
If you later want to use the source code, you find it in the directory /sources. Please contact us for
newer versions.
2.3 CARD AND DRIVER INSTALLATION
2.3.1 CHECK YOUR APIC CONFI URATION
The APIC improves the interrupt control in your system. The APIC will dramatically increase the
performance of the PC. It is installed together with the Power Manager while Windows installation.
Check it as follows:
•Windows 2000
Open “Einstellungen / Systemsteuerung / System / Hardware” (“Configuration / System control /
System / Hardware”) and start the “Geräte Manager” (“Device Manager”). It appears a list of
devices. The information about the APIC is in the submenu “Computer”.
•Windows XP
Open “Systemsteuerung / System / Hardware” (“System control / System / Hardware”) and start
the “Geräte Manager” (“Device Manager”). It appears a list of devices. The information about the
APIC is in the submenu “Computer”.
The APIC is installed, if the “ACPI-Uniprocessor-PC” is shown in “Computer”. If only “Standard PC”
is found there, even the changes of the BIOS will not help, to make Windows use the APIC. If you
find the entry “Standard PC”, you can follow the instructions in the APIC configuration.
2.3.2 CARD INSTALLATION
Switch off the PC.
Remove the power completely, because PC's keep the supply voltages at the PCI slots on, if the PC
is only shut down.
Manual Anfatec PCI-Lockin Amplifier AMU2.4 – Rev. 1.10 dated 30/09/20 Page 8 (70)

Plug the card in one of the PCI-slots of your PC and switch on again. Start the setup.exe on the
CD. All related files are copied to the related directories.
2.3.3 DRIVER INSTALLATION
•Windows 2000/ Windows XP
While Windows boots, it finds new hardware. Log in as administrator. WindowsTM will mention,
that it has found new hardware on your computer. If the software is not yet on your computer, you
can copy the recommended files now to your hard disk.
Check the second point, which means “Treiber aus einer Liste auswählen”. Say OK and give the
path to the “lockin.inf” (for instance: C:\Programme\Anfatec\LockIn\Driver) with the button
“Durchsuchen” (“Search”). Check the driver “LockIn Interface” and finish with “Fertigstellen”
(“Finish””).
•Later re-installation of a driver
Log in as administrator and call in the “System control” the topic "system". Chose the card
“hardware“ and open the “device manager”. It shows all hardware components installed on your
PC. With a double click on the "Anfatec Measurement Unit", the submenu "Anfatec Measurement
Unit" or “Anfatec LockIn” is opened. A second double click opens a window, which shows the
properties of the device.
Select the card “Driver” and start the button “Driver actualisation”. A dialogue is opened, which
asks: “Do you want to actualise the driver?”. In the next window please check the second option
“Search for a suitable driver” and click “OK”. At the question, where the driver is, the right path
has to be given as “other sources”. It is the path, where the new *.inf file is located. Eventually,
you have to select again the right device from a list of possible devices. Check the Anfatec
Measurement Unit again and say “OK” and “Finish”. The PC has to be rebooted in order to activate
the new driver.
2.4 CONNECTIONS TO THE CARD
Manual Anfatec PCI-Lockin Amplifier AMU2.4 – Rev. 1.10 dated 30/09/20 Page 9 (70)
Figure 1: Photograph of the LockIn board and description of the location of the single parts.

Connect the reference output to the excitation
input of your experiment. The signal input has
to be connected to the signal to be analysed.
The microscope control is used for the external
D/A- and A/D-channels, which can be updated
any time.
This card supports digital data outputs, only.
The connector “Controller” provides a digital
reference output signal as 2.8 V LVTTL wit the
same frequency like the sine wave at the “Out”
connector.
2.5 APIC CONFI URATION
Attention: this change is critical for your system. It can cause that your computer
refuses to boot. Only administrators should perform this action.
The way to switch on the APIC later, if the system has been installed as “Standard PC” without
Power Management, is described in detail in the computer magazine C't 19/03 on page 190/191 in
German. It works as follows:
Double click on the “Standard PC” icon and say “actualise driver” (Treiber aktualisieren). Check the
second line: “Show all known drivers”. Say OK and check again, that all known hardware
components for this device class are shown (“Alle Hardwarekomponenten dieser Geräteklasse
anzeigen.”. It appears a list on the right sight, which shows “standard PC”, “ACPI-Uniprocessor-PC”
and others. Select now the “ACPI-Uniprocessor-PC” and say OK. Because this change can cause a
real damage on your system, the computer will ask you “Do you really want to exchange this
driver?”. Say “Yes” and complete with “finish”.
When the computer restarts, you have to go into the BIOS setup now! Press “Entf” or
“Del” button on your keyboard during system reboot. In the BIOS, switch on the ACPI mode with
“ACPI Aware O/S = Yes” under the Power Management menu. For most BIOS types, this is only
one point to change. But for some BIOS, the APIC, which is part of the ACPI, has to be switched
on separately. Therefore, check your BIOS settings careful, that the APIC is really switched on.
If the computer does not reboot alone now, you have to reset and to repair your system from the
Windows Installation CD.
Remark: Wrong BIOS settings can cause, that Windows refuses to repair the system from CD. It
will stop with “could not find ntkrnlmp.exe – error code 7” for instance.
Manual Anfatec PCI-Lockin Amplifier AMU2.4 – Rev. 1.10 dated 30/09/20 Page 10 (70)
Figure 2: Connections to the LockIn card.
• Figure 3: Pinout of the connector "Controller"
or "Microscope Out".