Analog In And Trigger In; Analog Out And Trigger Out - THORLABS HPLS301 User Manual

Free-Space Plasma Light Source
NOTE: The shutter button on the front panel is always operational, even when external control mode is enabled.
Pressing the shutter button changes the shutter state and disables the external control mode. The shutter button
on the Front Panel is always active for safety reasons .

5.5.2. ANALOG IN and TRIGGER IN

In external control mode, the light intensity tuning knob on the front panel is disabled. Users can control the light
intensity by sending signals to the "ANALOG IN" and "TRIGGER IN" ports on the back panel.
The "ANALOG IN" female BNC port accepts 0 to 5 V analog signal input. Input voltage signals of 0 V and 5 V
correspond to 1.5% and 100% transmitted intensity respectively.
The light source does not respond to the input on "ANALOG IN" on its own. In order for the voltage signal on
"ANALOG IN" port to cause a change in the intensity, a trigger signal must be sent to the "TRIGGER IN" port. This
female BNC accept 5 V CMOS. When the falling edge of the pulse sent to the "TRIGGER IN" port is detected, the
light source will start to change the transmitted intensity to that specified by the voltage on the "ANALOG IN" port.
Port Name
ANALOG IN
TRIGGER IN

5.5.3. ANALOG OUT and TRIGGER OUT

The HPLS300 series light sources also have two female SMA ports on the back panel for monitoring the light
source.
The "ANALOG OUT" female SMA port outputs a 0 to 5 V signal that is proportional to the intensity percentage of
the light source.
The "TRIGGER OUT" female SMA port outputs a 5 V CMOS. The output is in high state by default. When the light
source starts intensity tuning, "TRIGGER OUT" outputs low state until the intensity tuning is finished.
Port Name
ANALOG OUT
TRIGGER OUT
Both "ANALOG OUT" and "TRIGGER OUT" are functional all the time, even when external control is disabled.
Rev C, June 12, 2019
Connector Signal Type
BNC Female 0 to 5 V
20 kΩ Impedance
BNC Female 5 V CMOS
Connector Signal Type
SMA Female 0 to 5 V
20 kΩ Impedance
SMA Female 5 V CMOS
Signal definition
Light source sets the output light
intensity percentage propotionally
to the input voltage
High: 3.5 to 5 V
Low: 0 to 1.5 V
Trigger at falling edge of a pulse
Pulse width >0.1 ms
Signal definition
Output voltage is propotional to the
intensity percentage
High: 4.3 to 5 V
Low: 0 to 0.55 V
Outputs high by default;
Outputs low during intensity tuning.
Chapter 5: Operation
Page 9