User`s guide

2 Installation

38 Model N6705 User’s Guide

1. Twist leads

2. 4-wire

disabled

(indicator

is off)

3. 4-wire

enabled

(indicator

is on)

Connect the load to the output terminals using separate connecting

wires. Keep the wire-pair as short as possible and twist or bundle it

to reduce lead inductance and noise pickup. Keep the load leads

under 14.7 meters (50 feet) per lead because of inductance effects.

Connect the sense leads as close to the load as possible. Do NOT

bundle the sense wire-pair together with the load leads; keep the load

wires and sense wires separate. The sense leads carry only a few

milliamperes of current and can be a lighter gauge than the load

leads. However, any voltage drop in the sense leads can degrade the

voltage regulation of the instrument. Try to keep the sense lead

resistance less than about 0.5Ω per lead (this requires 20 AWG or

heavier for a 50 foot length).

Agilent Models N678xA SMU require remote sensing when using any

of the High output bandwidth modes discussed in Chapter 6. Also,

these models have additional wiring restrictions as discussed under

“Agilent N678xA SMU Wiring Requirements”.

After turning the unit on, activate 4-wire remote voltage sensing by

pressing the Settings key. Navigate to and select Advanced. In the

Sense dropdown list select 4-Wire.

+ +

A B

2 3