IC-HTP Datasheet, PDF (2/51 Pages) IC-Haus GmbH – DUAL CW P-TYPE LASER DIODE DRIVER

iC-HTP
DUAL CW P-TYPE
LASER
DIODE
DRIVER
preliminary
Rev B1, Page 2/51
DESCRIPTION
Dual CW laser diode driver iC-HTP can operate two
individual laser diodes with up to 750 mA laser cur-
rent depending on the heat dissipation. Each channel
can be enabled independently. The laser diode driver
can be controlled by an external microcontroller (MCU
mode) or operate stand alone with pin/resistor config-
uration (iC-WK mode). In MCU mode, both channels
can be combined for driving up to 1500 mA.
Each channel can be operated individually either in
automatic current control (ACC) or automatic power
control (APC). All parameters including the internal
reference voltages are set via serial communication
(I²C or SPI). A 10 bit resolution D/A converter with
logarithmic characteristic is used for setting the oper-
ating point. This allows an operating point resolution
better than 1%.
In APC control, the monitor diode photocurrent is used
to track the optically emitted power of the laser diode.
The feedback for the laser diode driver is the voltage
of the photocurrent at a monitor resistor. An 8 bit inter-
nal programmable logarithmic monitor resistor (PLR)
or an external monitor resistor can be selected for
closing the control loop. The PLR ranges from 100 Ω
to 500 kΩ with a step width less than 5%.
In ACC control, the laser diode current can be set
directly. Current ranges are selectable.
iC-HTP allows disabling the laser channels when an
overcurrent threshold has been exceeded. The over-
current threshold of each channel has 2 ranges and is
programmable through an 8 bit linear D/A converter.
The temperature monitor measures the internal chip
temperature. iC-HTP disables the laser channels
when overtemperature is detected.
A variety of voltages can be measured with a 10 bit
A/D converter. The following voltages can be mea-
sured:
• V(LDAx)
• V(VBLx)
• V(VDD)
• V(VB)
• V(PLRx)
• V(MDKx)
• V(RACCx)
The DCO current output pin can control an external
DC/DC converter. Controlling the DC/DC output volt-
age can optimize the power dissipation of the whole
system e.g. to extend battery life or reduce total power
consumption.
iC-HTP in standby mode has a very low current con-
sumption (< 10 µA) and does retain its configuration.
The device features for safe operation:
• Configuration verification
• Tri-state configuration pins
• Write protection in operating mode
• Safe default/startup state
• Software parameter controllable channel disabling
• Hardware pin controllable channel ensabling
• Configuration timeout for access monitoring