Products

PC Power Distribution System

The “DC Power Distribution System” is designed for the low voltage supply of many different electronic devices that are relatively close together. This is usually observed in physics experiments on optical tables where a large number of different electronic devices need to be powered. In such environments, many wall plug-in power supplies are often found or several adjustable laboratory power supplies are used. Such solutions are cumbersome, prone for incorrect voltage settings combined with inadequate current limitation and hard to debug.

For cleaning up the power supply system in physics experiments with many electronic devices the “DC Power Distribution System” is a perfect solution. Each of its ten output channels can be current limited separately (eFused) and the outputs are automatically switched off when an incorrect input voltage is applied. Further, each output channel can be current- and voltage-monitored and switched on/off manually. All these features significantly increase the reliability and the safety of the power supply system.

The "DC Power Distribution System" is available for these standard voltages: ±5 V, ±12 V, ±15 V (±18 V).

Each voltage has its own plug system, which prevents from accidentally confusing the different voltages of an experiment. Please note that the bipolar power supply that must be connected to the back of the "DC Power Distribution System" is not included – it must be selected and purchased by the user.

To download the user manual, please click here.

Balanced Photo-Detector (SP 1’023)

This Balanced Photo-Detector (BPD) combines large bandwidth (50 MHz) with low noise performance. At 1 MHz the typical dark noise density is only 1.7 pA/sqrt(Hz). At a wavelength of 800 nm this corresponds to an optical power noise density of 3.2 pW/sqrt(Hz). At an optical power of 8.3 μW (@800 nm) on both photodiodes, the shot-noise density reaches to the dark noise density. The device is equipped with two large-area (d = 0.8 mm) silicon PIN-photodiodes (Hamamatsu S5972). Those cover an optical wavelength range from 320 nm to 1 μm. At 800 nm these photodiodes have a quantum-efficiency of around 84%. Since the photodiodes are mounted on sockets they can be changed easily. They can also be replaced by other low-capacitance photodiodes, covering different wavelength ranges.

The BPD has a gain of 1E4 V/A and the broadband output signal drives up to ±3.5 V when terminated with 50 Ohm. Several monitor signals (I-PD+, I-PD-, I-PD Diff) are available for DC-readout or slow-control; they are also very handy when setting up and adjusting an optical experiment.
With the M4 mounting-thread at the bottom the BPD can be mounted directly onto an optical table. Since the mounting-adapter is made out of plastics the device remains electrically isolated from the optical table.In combination with the included floating power supply no ground-loops can occur.

User Manual

The "High-Gain" version (1E5 V/A) of the Balanced Photo-Detector has a better noise performance but a reduced bandwidth of 15 MHz. At 0.5 MHz a typical dark noise density
of only 0.6 pA/sqrt(Hz) is reached; this corresponds to an optical power noise density of 1.1 pW/sqrt(Hz) at 800 nm.

HIGH-GAIN User Manual

This 1 MHz differential voltage amplifier combines low input voltage noise and low offset voltage drift. This combination is important for long-lasting measurements on samples at cryogenic temperatures. Commercial available amplifiers suffer from higher voltage noise or lower offset voltage stability over temperature and in time.   Low input voltage noise is reached by using a discrete dual J-FET (IF 3602) in the input stage. The offset voltage drift of this low noise J-FET input stage is reduced by a precise servo control-loop. The voltage gain can be switched between x100, x1'000, x10'000 and a variable LP-Filter (100 Hz... 1 MHz) is also integrated. At a gain of x100 an input differential voltage up to ±100 mV can be  amplified linearly. The amplifier can be AC or DC coupled, the input resistance can be switches between 10 MOhm, 1 GOhm and infinite (DC-only) and the common-mode voltage can be up to ±1 V. All these features make the Low Noise / Low Drift Differential Amplifier a versatile laboratory preamplifier.   To download the data sheet (SN 001...021) click here.(Version 1.0)  To download the data sheet (from SN 022) click here. (Version 2.1)

This 1 MHz differential voltage amplifier combines low input voltage noise and low offset voltage drift. This combination is important for long-lasting measurements on samples at cryogenic temperatures. Commercial available amplifiers suffer from higher voltage noise or lower offset voltage stability over temperature and in time. 

Low input voltage noise is reached by using a discrete dual J-FET (IF 3602) in the input stage. The offset voltage drift of this low noise J-FET input stage is reduced by a precise servo control-loop. The voltage gain can be switched between x100, x1'000, x10'000 and a variable LP-Filter (100 Hz... 1 MHz) is also integrated. At a gain of x100 an input differential voltage up to ±100 mV can be  amplified linearly. The amplifier can be AC or DC coupled, the input resistance can be switches between 10 MOhm, 1 GOhm and infinite (DC-only) and the common-mode voltage can be up to ±1 V. All these features make the Low Noise / Low Drift Differential Amplifier a versatile laboratory preamplifier. 

To download the data sheet (SN 001...021) click here.(Version 1.0) 
To download the data sheet (from SN 022) click here. (Version 2.1)

Low Noise | Low Drift Amplifier: Remote Control Interface (SP 1'004a)

For best performances the Low Noise / Low Drift Differential Amplifier (SP 1'004) should be installed as close as possible to the sample. Optimally it is attached directly to the breakout-box on top of the cryostat which is often hard to access during running experiments. This Remote Control Interface allows controlling the voltage-gain and LP cut-off frequency via a flat-cable with a length of serval meters. In addition, the OVERLOAD and OFFSET-COMPENSATED status of the amplifier is readout by the Remote Control Interface. Since the remote control inputs on the LNLD Differential Amplifier are galvanically isolated by optocouplers no ground loops can occur by using this remote control. The Remote Control Interface comes with a 2.8'' touchscreen for manual control and has a serial port (RS-232) for simple ASCII communication with a computer. 

This Remote Control Interface is based on a single-board Raspberry Pi B+ computer running a Linux operation system. 

To download the user manual, please click here

Optical Intensity Stabilization – OIS (SP 999)

For the intensity stabilization of lasers and other light-sources the Optical Intensity Stabilizationcan be used. The OIS is a tiny box containing an optical detector (PIN-photodiode and amplifier) a PID-controller, a stable reference value and a 50 Ohm driver unit. The versatile OIS-box can be mounted directly onto an optical table with an M4 thread. The large area (7 mm2) photodiode is mounted in the center of a 30 mm cage plate (SM1, CP02/M from Thorlabs) and has a bandwidth of 500 kHz. It is suitable for wavelengths in a range from 400 nm to 1'100 nm. 

To download the user manual, please click here.

Low Noise | High Stability I to V Converter (SP 983)

The LNHS I to V Converter combines low input voltage noise with high stability and low drift input voltage (< ±0.2 μV/K). This combination is very important for measurements on samples at temperatures near the absolute zero. Commercial available I/V converters suffer from higher input voltage noise or lower input voltage stability over temperature. The gain can be selected in decades from 105 up to 109 V/A and the low-pass filter can be adjusted between 30 Hz and 100 kHz. These settings can also be done remotely by using the Remote Control Interface (SP 983a). At the maximum gain (109 V/A) the bandwidth is typical 1.6 kHz and at the minimum gain (105 V/A) reaches 600 kHz. By applying an external voltage the input offset voltage can be varied within ±100 mV. 

The device can be equipped with two different J-FETs in the input stage:

1) STANDARD: LSK389A

PRO: Lower input current noise (significant in the 108 and 109 V/A ranges) CON: Slightly higher input voltage noise. Smaller gain-bandwidth-product (68 MHz) increases output noise at large input-capacitances. 

Data Sheet STANDARD

2) HIGH-GBWP: IF3602 

PRO: Slightly lower input voltage noise. Lager gain-bandwidth-product (620 MHz) makes output noise significant smaller at large input-capacitances. CON: Higher input current noise (significant in the 108 and 109 V/A ranges) 

Data Sheet HIGH-GBWP

Low Noise | High Stability I to V Converter (SP 983c)

The version SP 983c of the "LNHS I to V Converter" is completely the same as the SP 983 above, only that the external applied input offset voltage is internally subtracted and is no longer on top of the output signal.
This option was demanded by users sweeping or altering the input offset voltage of the "LNHS I to V Converter".

The device can be equipped with two different J-FETs in the input stage:

1) STANDARD: LSK389A

PRO: Lower input current noise (significant in the 108 and 109 V/A ranges)CON: Slightly higher input voltage noise. Smaller gain-bandwidth-product (68 MHz) increases output noise at large input-capacitances.

Data Sheet STANDARD (SP 983c)

2) HIGH-GBWP: IF3602 

PRO: Slightly lower input voltage noise. Lager gain-bandwidth-product (600 MHz) makes output noise significant smaller at large input-capacitances. 
CON: Higher input current noise (significant in the 108 and 109 V/A ranges)

Data Sheet HIGH-GBWP (SP 983c)

LNHS I to V Converter Remote Control Interface (SP 983a)

It is recommended to install the Low Noise / High Stability I to V Converter (SP 983) as close as possible to the sample. Therefore the I/V converter is often located in a places hard to access during running experiments. This Remote Control Interface allows for the remote control of the gain and LP cut-off frequency via a flat-cable with a length of serval meters. Since the remote control inputs on the LNHS I to V Converter are galvanically isolated by optocouplers no ground loops can occur. The Remote Control Interface comes with a 2.8'' touchscreen for manual control and has a serial port (RS-232) for simple ASCII communication with a computer. 

User Manual

This Remote Control Interface is based on a single-board Raspberry Pi B+ computer running a Linux operation system. 

Low Noise | High Resolution DAC (SP 927)

The LNHR DAC is an eight channel voltage source with exceptional low noise performance and high resolution. It is designed to drive high-ohmic gates with ultra-stable voltages in fundamental physics experiments at cryogenic temperatures. For such experiments constant DC bias-voltages and high resolution sweep-voltages with very low fluctuations are mandatory. The output range of ±10 V, combined with the 24 bit resolution, allows adjusting the voltages with a step size of only 1.2 μV. The output voltage noise is below 1 μVRMS, measured in a frequency range of 0.1 Hz to 100 Hz. With its bandwidth of DC…70 Hz the LNHR DAC can be used for DC-biasing, for ramping/sweeping and for low frequency waveform generation. The device can be controlled locally by the rotary/push knob (encoder) or remotely by using the RS-232 interface. The actual voltages can be displayed on the LCD. 

User Manual

User Manual 2.6 (from serial number 0051)

For fast switching between two output channels of the LNHR DAC use the Analog Selector Switch (SP 944). To generate precise voltages up to ±100 V use the HV-Amplifier (SP 908).

Analog Selector Switch (SP 944)

The Analog Selector Switch allows fast and low-glitch switching between two analog voltages in a range of up to ±10 V. To prevent from interferences and ground-loops the TTL-compatible control input is galvanically isolated by an optocoupler. The low noise performance combined with the low ON-resistance (<200 Ohm) and a charge-injection smaller than 1 pC makes this switch suitable for high-sensitive physics experiments. The device can be mounted directly to the BNC connectors on the front-panel of the LNHR DAC (SP 927) and allows fast switching (up to 100 kHz) between two different low noise output voltages. 

Data Sheet

HV-Amplifier (SP 908)

If the standard ±10 V voltages, generated from the LNHR DAC (SP 927), are too low the HV-Amplifier with a voltage gain of ten can be used. It has an output voltage of up to ±100 V with a maximum output current of ±70 mA. To prevent from ground loops, the analog in/out are floating and not referenced to the ground/earth carried by the 230 V mains. An analog voltage-indicator on the front-panel shows the actual output voltage. The device can be used to drive capacitive-loads such as piezo-electrical crystals. The bandwidth can be switched between 10 kHz and 100 kHz; this makes it compatible with the Analog Selector Switch (SP 944). 

Data Sheet

Magnetic Field Stabilization (SP 962)

The Magnetic Field Stabilization allows fast and precise controlling/stabilization of the magnetic field at certain location of the experiment. By using a magnetometer (e.g. from Bartington) the actual magnetic field is measured and a Helmholtz-coil driven by an external low-noise current source is used to control the field. The device is installed between the magnetometer and the coil driver current source. For controlling/stabilization of all three space axes three such devices are needed. The PID controller can be adjusted by potentiometers on the front-panel. For fast and precise switching the magnetic field the device automatically changes between PID- and PD-controller, depending on the output voltage of the coil driver current source. This reduces the switching-time of the magnetic field without over/under-shooting by more than a factor two. 

Detailed Description (available in German)

Piezo-Motor Controller PMC (SP 869)

The Piezo-Motor Controller offers the flexible and robust operation of up to eight slip-stick piezo-motors. It allows a bidirectional movement in up to eight axes (channels), whereas only one axis can be driven at the same time. The PMC can drive a wide range of piezo-motor capacitances up to 15 nF. The saw-tooth output voltage of the PMC has a fast back-jump (slip) rise/fall time of only 1 μs at a load-capacitance of 10 nF. This leads to efficient and reliable operation of slip-stick piezo-motors also at cryogenic temperatures. The applied saw-tooth voltage can be adjusted from zero up to ±400 V and the frequency from 1 Hz up to 4 kHz. The PMC can be operated by the Hand-Control Unit (SP 869a) or via a computer-control interface.

User Manual


Contact

Electronics Lab
Departement of Physics
University of Basel
Klingelbergstrasse 82 (Offices: 2.17 & 2.21)
4056 Basel, Switzerland

T +41 (0)61 207 37 22
F +41 (0)61 207 37 84

Head Electronics Lab

Team