Keithley 2520, Руководство по обслуживанию, Страница: 119 / 137

HW
Rev. D
2/26/03
2520 Pulsed Laser Diode Test System
Notes
1
1 year, 23°C ±5°C.
2
If Cycle Duty ·1 exceeds 0.2, accuracy specifications must be derated with an additional error
term as follows:
500mA Range: ±0.1% rdg. · D ·1
5A Range: ±0.3% rdg. · D ·1
where: I = current setting
D = duty cycle
This derating must also be applied for a period equal to the time that D ·I was • 0.2.
3
Not including overshoot and setting time.
4
Pulse mode only.
5
Output: 500mA DC on 500mA range and 1A DC on 5A range.
6
Refer to 2520 Service Manual for test setup of current accuracy.
7
Figures 1 and 2 are typical pulse outputs into resistive loads.
8
Typical
9
Per ANSI/IEEE Std 181-1977.
10
Per ANSI/IEEE Std 181-1977 10% to 90%.
11
DC accuracy ±700mV @ output terminal. 0.2 : typical output impedance.
12
At DC, 10μs measurement pulse width, Filter off.
13
Standard deviation of 10,000 readings with 10μs pulse width, filter off, with I source set to 0
amps DC.
14
The A/D converter has 14 bit resolution. The useful resolution is improved by reading averaging.
The useful resolution is:
Setting Filter Averaging
100ns
400ns (ns) Width Pulse
1
2
Range
Resolution Useful
14
˜
˜
15
Excluding total programmed (Pulse ON time + Pulse OFF time).
16
Front panel off, calc off, filter off, duty cycle < 10%, binary communications.
17
Returning 1 voltage and 2 current measurements for each source point.
18
Sweep mode.
19
Valid for both continuous pulse and sweep modes.
20
Shown is the Power Distribution % based on current settings.
21
Timing Cycle (
pw
/
(pw
+
pd)
): 4% max.
Specifications are subject to change without notice.
Pulse Waveform Flatness - 500mA Into 20 Ohms
0
0.1
0.2
0.3
0.4
0.5
0.6
0 5 10 15 20 25
Time ( s)
0.485
0.49
0.495
0.5
0.505
0.51
0.515
Full Pulse
Current
(A)
Current
(A)
Expanded Pulse Top
Figure 1
Pulse Waveform Flatness - 5A into 2 ohms
0
1
2
3
4
5
6
0 5 10 15 20 25
Time ( s)
4.94
4.96
4.98
5
5.02
5.04
5.06
Expanded Pulse Top
Full Pulse
Current
(A)
Current
(A)
Figure 2
Pulse Output/Trigger Output Relationship
-2
-1
0
1
2
3
4
5
6
-1.00E-06 -5.00E-07 0.00E+00 5.00E-07 1.00E-06 1.50E-06
Time
Volts
Pulse
Trigger
Figure 3
Model 2520 Pulsed Laser Diode Test System Service Manual Specifications A-7