Control commands
lason
: Should be set to 1 to enable the laser current (default value: 0)
ilaser
: Laser current in mA (default value: 0.0).
rtset
: Thermistor resistance setpoint in Ω (default value: 10000.0).
pgain
: Proportional gain of the temperature controller (default value: 0.001).
igain
: Integral gain of the temperature controller (default value: 0.0001).
dgain
: Differential gain of the temperature controller (default value: 0.0005).
rtmin
: Minimum thermistor resistance in Ω. Below this value, the laser is automatically
disabled (default value: 5000.0).
rtmax
: Maximum thermistor resistance in Ω. Above this value, the laser is automatically
disabled (default value: 15000.0).
vtmin
: Minimum TEC voltage in V (default value: -2.0).
vtmax
: Maximum TEC voltage in V (default value: 2.0).
Status commands
version
: Return the firmware version (e.g. V0.1)
lason
: Laser status (0 when disabled, 1 when enabled)
vlaser
: Laser voltage in V.
iphd
: Photodiode current in mA (maximum value: 2.5 mA).
rtact
: Actual value of the thermistor resistance in Ω.
itec
: TEC current in A.
vtec
: TEC voltage in V.
ain1
: Voltage on pin AIN1 in V.
ain2
: Voltage on pin AIN2 in V.
Configuration switch
Switch 1
: When SW1 is ON, the user configuration is loaded at start-up. When SW1 is OFF,
the default configuration is loaded at start up.
Switch 2
: SW2 is used for firmware update. It should be kept OFF for normal operation.
Status LEDs
STATUS
: Always ON during normal operation
LASER
: Turns ON when the photodiode current is above 10 mA.
TEMP
: Turns ON when the thermistor resistance is within 1 Ω of the setpoint.
Modulation inputs
The CTL200 has two current modulation inputs available on SMA connectors:
DC modulation input
for modulation between DC and 10 MHz. Modulation range is +/- 1
V. A jumper allow to choose between 3 modulation gains (200 µA/V, 2 mA/V or 20 mA/V
for the 200 mA version).
AC modulation input
for modulation above 100 kHz. Modulation gain is 20 mA/V.
