Optionally, either the optical output power (via APC), the laser diode current (using ACC), or a fully controller-based control can be used to control the laser diodes. The laser diode current is measured with the voltage drop at the shunt. The maximum laser diode current per channel is defined via an external power transistor and is scalable across a wide range from a few mA up to several amps. In addition, an automatic overcurrent shutdown is adjustable. Due to the high integration of the analogue functions for controlling and regulating the laser diodes with the microcontroller interface, powerful laser diode controllers can be implemented easily and compactly. Internal operating points and various voltages can be output via analog-digital converters.
The integrated temperature sensor allows monitoring of the system temperature also for feedback in the control loop. Logarithmic digital-to-analog converters provide optimal optical power control across a wide dynamic range for a variety of applicable laser diodes and LEDs. The respective configuration is stored in two equivalent memory areas. Internal current limits, supply voltage monitoring, an interruption switch input, and a watchdog ensure operation of the laser diode or LED via the iC-HTG. The device is controlled via an SPI or I²C interface. The iC-HTG operates with a supply voltage range of 3 to 24 V and thus also drives blue and green laser diodes as well as stacks (series circuits with several laser diodes). Operating in the -40 to +85°C temperature range, the device is housed in a 24-pin 5x5mm QFN package.
iC-Haus - www.ichaus.com