Keithley 6487 Reference Manual

7-6 Triggering Model 6487 Reference Manual
Trigger-In source — The Trigger-In control sources are explained as follow:
• Immediate (TRIGger:SOURce IMMediate) — Event detection for the trigger
layer is satisfied immediately allowing operation to continue to perform a
measurement.
• TLink (TRIGger:SOURce TLINk) — Event detection for the trigger layer is satis-
fied when an input trigger via the TRIGGER LINK connector is received by the
Model 6487. Note that if the source bypass is set to ONCE (TRIGger:DIRection
SOURce), operation will loop around the source detector on the initial pass
through the arm layer. Detection for each subsequent pass is satisfied by an input
trigger. The bypass resets when the Model 6487 leaves the trigger layer.
Trigger delay
A programmable delay is available after event detection. It can be set manually (0 to
999.9998 seconds) or an auto delay can be used. With auto delay selected, the Model 6487
automatically sets delay according to range. The auto delay settings are listed in Table 7-1.
Table 7-1
Auto delay settings
Range Delay
2nA
20nA
200nA
2μA
20μA
200μA
2mA
20mA
10ms
10ms
10ms
10ms
5ms
5ms
1ms
0.5ms

Keithley 6487 Specifications

General

Type	Picoammeter/Voltage Source
Current Measurement Range	20 fA to 20 mA
Interfaces	GPIB, RS-232
Voltage Burden	< 200 µV
Input Impedance	>10^14 Ω
Power	100 V / 120 V / 220 V / 240 V
Basic Current Measurement Accuracy	0.4%