OsTech Laser Lab Source LDC Series, Руководство по эксплуатации

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t
LMDIC
=
2
LMW
and
LMP
as in continuous pulse mode
LMDIC
: 0 . . . 64000
LMDIC
=
0 continuous pulse mode
LMDIC
=
1 single pulse mode
LMDIC
=
2 . . . 64000 n-pulses mode
Figure 5.3:
single pulse mode, n-pulses mode
the number of pulses will be generated. Afterwards, the driver enters the OFF state
automatically. You don’t need to enter
LS
.
Assigning 0 to
LMDIC
switches to the continuous pulse mode described above.
External trigger mode
To switch to this mode activate the gate option in single pulse mode/n-pulses mode.
The gate option (see section 5.3 ) has a different meaning in this mode. Activating
it enables you to trigger the beginning of the generated pulses externally. If
LGR
is
activated and
LR
was entered the driver generates the defined number of pulses as
soon as a low-high transition at the modulation input occurs.
5.4.2 External Digital Modulation
The external digital modulation mode may be activated by entering the LMDX com-
mand. If this mode is active and the laser is run (
LR
) then the laser is activated by
a TTL high-level at the modulation input and vice versa. The command
LMDXNR
negates this logic so that the laser will be activated by TTL low-level. This mode is
similar to the CW mode with the gate option activated. However, in this mode you
can set a laser bias current (
LCB
).
5.4.3 External Analog Modulation
The external analog modulation mode is selected by entering the
LMAX
command.
In this mode the laser current can be controlled by the voltage at the AMOD input
where 4 V corresponds to I
max
. The compliance voltage (
LVC
) has to be set before
and the laser has to be run by
LR
.
The input has an internal terminating resistor of 10 k Ω . If you want to connect e.g.
a 10 V signal, you should use a 15 k Ω resistor in series externally.
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