Sutter Instrument Lambda 421, Operation Manual

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LAMBDA 421 OPERATION MANUAL – REV. 1.00N (20170623)
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In addition to the computer interfaces, there is the Strobe input, which is used as a trigger in
the ring buffer mode. There is an analog output and a digital output that are both used to
indicate the currently selected filter. The analog output (DAC) produces a voltage of 0 to 6
volts in 16 steps. Each increment in the filter value adds 0.4 volts to the output voltage. The
digital output is a binary representation of the currently selected filter number.
Table 1. Selecting channel light source intensity via external-control filter value commands.
FILTER
VALUE
LED
SELECTED
SUGGESTED
CURRENT
0 NONE 0%
1 1 100%
2 2 100%
3 3 100%
4 4 100%
5 1 50%
6 2 50%
7 3 50%
8 4 50%
9 1 33%
10 2 33%
11 3 33%
12 4 33%
13 1 15%
14 2 15%
15 3 15%
The actual attenuation is determined by the DAC value associated with each filter value.
These are programmed as indicated in the previous table. However, each value can easily be
changed from external software.
The new Lambda 421 has a new series of trigger options for the ring buffer. Triggering on
the rising edge or the falling edge of the trigger signal can be selected. A special mode that
allows the level of the trigger signal to also control the shutter function is also available. This
allows a typical shutter control signal to advance the filter selection in the ring buffer while
also controlling the on/off state of the light.