Agilent Source Monitor Unit (SMU) Fundamentals 3-SMU Fundamentals c20130117 [1] free download

File name Source Monitor Unit (SMU) Fundamentals 3-SMU_Fundamentals c20130117 [1].pdf

Excerpt Edition This PDF is an excerpt from Chapter 3 of the Parametric Measurement Handbook. The Parametric Measurement Handbook Third Edition March 2012 Chapter 3: Source/Monitor Unit (SMU) Fundamentals "You do not really understand something unless you can explain it to your grandmother." -- Albert Einstein SMU overview Introduction The primary measurement resource for parametric test is the source/monitor unit or SMU. This is also sometimes also referred to as a source/measurement unit, although the acronym ends up the same. The SMU can force voltage or current and simultaneously measure voltage and/or current. The diagram below shows a simplified SMU equivalent circuit: A V Figure 3.1. Simplified SMU schematic. Since SMUs must measure very low currents (1 fA or less), they always have triaxial outputs for the reasons discussed in the previous chapter. There are a variety of different types of SMUs. The most common SMU is the medium-power SMU (MPSMU); as the name implies this SMU can supply moderate levels of voltage and current (