U1c - Cross-point Matrix

U1c front panel


The U1c is essentially a switch board - allowing the user to make or break a connection between ‘input’ points to ‘output’ points fitted on the module. Each connection can be set individually to an ‘open’ or ‘closed’ state.

There are 8 ‘input’ connectors (a.k.a. ‘sample’/DUT connectors) and 8 ‘output’ connectors (‘instrument’ connectors). This gives the user a grid of 64 possible connections, fully-configurable per each single connection. See illustration below.

U1c Full Grid Diagram

Therefore the U1c can: * Rotate / sweep across multiple sample points with single source & measurement instruments * Fan out an instrument with limited connections to multiple samples - simultaneously or sequentially * Link samples - short multiple samples together * Fix non-stimulated sample locations to an external bias or GND.

The U1c is especially designed to work with delicate sensitive samples. In general, switching hardware may introduce transient voltage spikes and charge injections during switching, and DC leakage currents. The U1c is designed to minimize such interference and is fitted with RC filters on all external connectors. It is also recommended to use the U1c module together with the stand-alone Matrix Module (matrix rack), which adds further filtering.

Particular attention was given to protecting the ‘sample’ contacts, hence a tighter filtering was applied to the sample connectors. Additionally, sample-side connections are kept by default at GND via a weak pull-down to prevent charge accumulation. These safeties make the module not symmetrical - the ‘sample’ and ‘instrument’ connectors are not equivalent. Therefore the U1c is not suitable for transient measurements, but is intended for steady-state measurements.


Parameter Value Units Conditions
Static Characteristics
Roff Sample connector to instrument connector
Ron Sample connector to instrument connector
R leakage Sample connector to ground
C sample-instrument pF
C sample-sample 5 pF Typical
Dynamic Characteristics
Switching Rate