Continuous wave laser diode driver features MCU interface
A laser diode driver that permits MCU-based driving of laser diodes with common cathodes or P-type laser diodes in Continuous Wave (CW) mode has been introduced by iC-Haus. With the iC-HTP, either Automatic Power Control (APC), Automatic Current Control (ACC), or a full controller-based power regulation can be used.
For driving N-type and M-type laser diodes in CW mode, the laser iC-HT diode driver can be used. The maximum laser diode current per channel is 750mA. Both channels can be connected in parallel for higher laser diode currents of up to 1.5A. A current limit can also be configured for each channel. Due to the high integration level of the analogue functions for driving the laser diodes with a MCU interface, multi-channel laser diode control units can be implemented directly.
Internal operating points and voltages can be output through ADCs. The integrated temperature sensor permits the system temperature to be monitored and can also be used for feedback in the control circuit.
Logarithmic DACs allow optimal power regulation across a large dynamic range, enabling a variety of laser diodes to be used.
The relevant configuration is stored in two equivalent memory areas; internal current limits, a supply voltage monitor, channel-specific interrupt switching inputs, and a watchdog secure the operation of the laser diodes through iC-HTP.
Alternatively, the device can be operated by pin configuration instead of the SPI or I2C interface, where external resistors define the APC performance targets.
An external supply voltage can be controlled through the current output DCO to reduce the system power dissipation to a minimum, such as in battery-operated devices or systems.
iC-HTP uses supply voltages of 2.8 to 11V and can thereby drive both blue and green laser diodes. Operating temperatures range from -40 to +85°C. The device is packaged in a 28-pin 5x5mm QFN.
The design-in process is supported by ready-to-operate demo boards and software for evaluation with a PC.