Source Measure Unit (SMU)

Precision Voltage and Current Instruments

 

WHY AN SMU?

Source Measure Units test the multitudes of components produced every day! Their importance can't be overstated: SMUs verify that components meet their specifications SO THAT electronic equipment - medical, communication, aviation, media - function correctly, accurately and reliably!

What types of components can be tested?

1. Passives - resistors, capacitors, inductors, etc.
2. Actives - diodes, BJTs, FETs, etc.
3. IC's - amplifiers, references, regulators, timers, etc.
    

WHY THIS SERIES?

Benefits of dicovering how SMUs work:

1. Showcases key areas of analog design:
    amplifiers, control loops, V-I sensing.
2. Provides deeper insight into component behavior.
3. Understand component specifications and tests.

TWO MODES

With just two operating modes, you can perform a variety of characterizations on the Device Under Test (DUT).

• Force Voltage, Measure Current (FVMI)
  • Tests:  resistance, leakage current, photo-voltaic V-I, etc.
  • Example - Audio Amp Input Resistance:  Rin = 50k ± 20% @ 10V
      Set FV = 10V, perform MI, Calc Rin = MV/MI and Check Limits.
• Force Current, Measure Voltage (FIMV)
  • Tests:  zener voltage, load regulation, battery discharge, etc.
  • Example - Zener Voltage:  Vz = 5.6V ± 2% @ 5mA
      Set FI = 5mA, perform MV, Check Limits.

 

1. BASICS

Understand the SMU's basic building blocks with tutorials and hands-on SPICE simulations.

Topic	Link
Basic SMU Blocks - Force Voltage (FV)	SMU FV
Basic SMU Blocks - Force Current (FI)	SMU FI

2. ADVANCED

Build knowledge and intuition of more complex SMU topics along with hands-on SPICE Simulations and Excel Design Calculators.

Topic	Link
Basic SMU Circuit - FVFI	SMU Schematic and Overview