Modules are removable cassettes that are placed in the slots of the rack. The SPI-rack has 12 (almost) identical slots (to be specific: they are divided in 4 supply/breakout groups of 3). Each module contains a specific function identified by the code. The modules are identified by a letter-number(-letter) code on the front.

The modules function can be determined by the first letter in the code: source (S–), measure (M–), controller (C–) etc. The second digit in the module code is a digit denoting a module category, and the third position (-) denotes a specific type within that category, usually a letter. For example: the S4g. The ’S’ denotes a source module, the ‘4’ indicates a current source and the ‘g’ a specific module type.

The tables below contain the modules that have been developed specifically for the SPI Rack. For the IVVI rack modules, see: The IVVI modules are compatible with the SPI Rack, provided that a IVVI Rack Compatibility module (B1/B2b etc.) is used. For more information, see IVVI Rack Compatibility.


Module Info
C1 - Non-Isolated Controller PC directly connected to the SPI Rack.
C1b/C2 - Isolated controller PC connected to C2 which has a galvanically isolated connection with the C1b.

Current Source

Module Output Range Info
S4g - 4 Channel, 18-bit current source ±50 mA, ±25 mA, +50 mA Span adjustable in software.

Voltage Source

Module Output Range Info
D5a - 16 Channel, 18-bit DAC ±4V, ±2V, +4V, (±8V, +8V) Span adjustable in software. ±8V and 8V possible with extra power supply. Slow ramp down switch for emergencies.
D5b - 8 Channel, 18-bit DAC + microcontroller ±4V, ±2V, +4V, (±8V, +8V) Hardware identical to D5a, with an added high speed ARM Microcontroller. Allows for complex/high speed local control. Can synchronise with D4b modules.
S5k - 16 Channel AWG

Voltage Measurement

Voltage Measurement Input Range Info
D4 - 2 Channel, 24-bit ADC ±4V High resolution ADC module. Can be used as an alternative to a Keithley DMM.
D4a - 2Channel, 24-bit ADC ±4V Redesign of the D4. Added functionality: can be used as break-out module and can do automatic calibration. Recommended over the D4.
D4b - 2 Channel, 24-bit ADC + microcontroller ±4V Hardware identical to D4, with an added high speed ARM Microcontroller. Can run at higher sample rates and store data locally. Can synchronise with a D5b module. In development


Module Frequency Output Info
S5i - RF Generator 40 MHz - 4 GHz -14 to 20 dbm Outputs square wave, needs external filtering
F1d - IQ Demodulator RF/LO from 40 MHz to 1.4 GHz Adjustable 1/3/10 MHz IF output Adjustable output gain
F1e - IQ Demodulator RF/LO from 40 MHz to 1.4 GHz Adjustable 200 MHz / 500 MHz IF Output In development
M2j - Low Noise Amplifier 40 MHz to 4 GHz Variable gain from 40 to 70 dB Noise Figure of 1.3dB at maximum gain


Module Info
S5t - 10MHz Sync Trigger Generates triggers divided from the 10 MHz reference.
S5l - Trigger processor Two trigger inputs and 4 outputs. Can be configured with different processing functions: splitter, AND, OR etc.
U2 - Cryomux control Control module for the cryogenic multiplexer PCB.

IVVI Rack compatibility

Module Info
B1a - Analog Break-in/Break-out Basic isolated analog input & output module for interfacing with IVVI modules.
B1b - Analog Break-in Contains software controlled switches to determine the routing of signals from the frontpanel to the IVVI modules.
B1c - Analog Break-in/Break-out MCX non-isolated inputs and outputs only. Can not connect to other measurement equipment.
B1d - Analog Break-out Dual channel isolated outputs. PCB based on IVVI M0a module.
B2a - Digital Break-out Contains a 2 channel 24-bit ADC.
B2b - Digital Break-out Contains a 2 channel 24-bit ADC + microcontroller. In hardware identical to the D4b module.
B2c - Digital Break-in/Break-out Contains 4 internal DAC channels and a dual channel 24-bit ADC.
B2d - Ditigal Break-in Contains 4 internal DAC channel and 2 isolated inputs.