Programming Example - Keithley 2520 User Manual

Model 2520 User's Manual
Table 4-2 (continued)
Laser diode test commands
Command
:SOURce[1]:CURRent:MODE FIXed
:SOURce[1]:CURRent:RANGe <range>
:SOURce[1]:CURRent <current>
:SOURce[1]:CURRent:POLarity <polarity>
:SOURce[1]:VOLTage:PROTection <limit>
:SOURce[1]:FUNCtion <function>
:SOURce[1]:PULSe:DELay <delay>
:SOURce[1]:PULSe:WIDTh <width>
:SOURce[1]:CURRent:LOW <low_current>
:SOURce2:VOLTage <voltage>
:SOURce3:VOLTage <voltage>
1
COND = I /V ; RES = V
L L
2
CURR1 = I ; VOLT1 = V
L
3
5.0A maximum pulse mode only. 1A maximum in DC mode.
4
Settings affected by maximum duty cycle. See

Programming example

Table 4-3
steps correspond to those listed previously in
See Figure 4-1
mation.
These commands set up the Model 2520 as follows:
•
•
•
•
•
•
•
•
•
•
/I ; POWER = V * I .
L L L L
; CURR2 = I ; VOLT2 = V
L PD1
Section
summarizes the command sequence for basic laser diode testing. Note that most
for basic circuit configuration and
Laser diode voltage measurement range and polarity: 10V, positive.
Detector measurement polarity: negative (both detectors).
Detector ranges: 10mA (detector #1); 50mA (detector #2).
Laser diode source: 0.5A range, +0.5A amplitude, 5V voltage limit, positive
polarity.
Laser diode source mode: pulse, delay = 200µsec, width = 10µsec, low I = 10mA.
Detector #1 bias source: +20V amplitude.
Detector #2 bias source: +10V amplitude.
Laser diode math function: power.
Detector #1 math function: MX + B, B = 2, M = 0.5.
Returned data: laser diode power, detector #1 MX + B math, detector #2 current.
Select fixed (not sweep) laser diode current source mode.
Select laser diode source range (0.5 or 5).
Set laser diode source current (0 to +5.0).
Set laser diode source polarity (POSitive or NEGative).
Set laser source voltage compliance limit (3 to 10.5).
Select laser diode current source function (DC or PULSe).
Set laser diode source pulse delay (20e-6 to 0.5).
Set laser diode source pulse width (500e-9 to 5e-3).
Set low pulse amplitude for pulse mode (0 to 0.015,
500mA range; 0 to 0.150, 5A range).
Set detector #1 source voltage (0 to ±20).
Set detector #2 source voltage (0 to ±20).
; CURR3 = I ; VOLT3 = V
B2 PD3
5.
"Front panel laser diode testing," page
Section 2
Laser Diode Testing
Description
3
.
B2
for detailed connection infor-
4-7
4
4
4-3.