User Manual

5-8 Pulse Mode Operation (Model 2430 only) 2400 Series SourceMeter

User’s Manual

NOTE With auto zero disabled, zero drift will eventually corrupt the accuracy of

the pulse measurement. To re-establish an accurate pulse measure

ment, enable auto zero or change the speed setting.

NOTE From the front panel, auto zero is controlled from the A/D CONTROLS

item of the Main Menu. For remote operation, the :SYSTem:AZERo com

mand controls auto zero.

Pulse-only

The fastest pulses are achieved by disabling measurements. With the signal not

measured, as shown in Figure 5-4, the pulse width can be as short as the

150µsec overhead. With reference and zero not measured, and display disabled,

the output off-time can be as short as the 1.9msec overhead.

NOTE Measurements cannot be disabled from the front panel. For remote oper-

ation, measurements can be disabled by sending the [SENSe]:FUNC-

tion:OFF:ALL command. See Section 18 for details. To disable the

display from the front panel, press CONFIG then EDIT, then select NOW.

Figure 5-4

Pulse-only timing

Pulse jitter

Pulse jitter is defined as the variance in the configured pulse on and off times. The

amount of jitter that can occur depends on how the SourceMeter is set up. For the

least amount of jitter (<5µsec for pulse on-time), turn off the display. See

Section 1, “Disabling front panel display.” With the display on, pulse on-time jitter

depends on the pulse width. For pulses <1msec wide, on-time jitter can be up to

20µsec. For pulses >1msec wide, on-time jitter is 5–40µsec.

Delay = Pulse width delay, used to achieve pulse width setting.

150µs = Minimum pulse width overhead

1.90ms = Minimum output off-time overhead

PD = Pulse delay setting, used to determine time between pulses.

1.9ms

0V or 0A

Pulse Width

(Output On-Time)

Output Off-Time

Delay 150µs