FEATURES

? iC-WK MSOP8 AEC-Q100 qualified (Grade 3)

? CW operation up to 90 mA from 2.4 to 6 V supply voltage

? Rapid soft start after power-on typical within 70 μs

? Simple power adjustment via the external resistor

? Control loop accuracy better than 1% with changes in

temperature, supply voltage and load current

? Integrated reverse polarity protection for the iC and laser diode

? Strong suppression of transients with very small external

capacitors; integrated flyback path

? Permanent shutdown with excessive temperature and

overcurrent (i.e. if the laser diode is damaged or the feedback

current path fails)

? Two feedback inputs permit all current LD types to be used

(N/P/M configurations)

? Modulation via the feedback inputs is possible

? Wide monitor current range from 10 μA to 2.5 mA

? iC-WK with additional spike detection at monitor input MDA

APPLICATIONS

? Battery-powered LD modules

? LD Pointers

? Laser levels

? Bar-code readers

DESCRIPTION

The iC-WK/L device is a driver for laser diodes in

continuous wave operation which requires only four

external components. The wide power supply range

of 2.4 to 6 V and the integrated reverse battery protection allow for battery operation with a minimum of two

cells. A reversed battery connection destroys neither

the iC nor the laser diode.

The iC includes integrated circuitry protecting against

destruction by ESD, excessive temperature and overcurrent and a soft start which regulates the power and

protects the laser diode when the power supply is

switched on. The iC also filters the laser diode power

supply for transients.

The power supply is regulated and adapted to the

laser diode used by an external resistor at MDA. The

monitor current acts as a reference and is regulated

independent of the influence of temperature and supply voltage (range: 10 μA to 2.5 mA). The capacitor at

CI determines the control time constants and start-up

time.

A second monitor input, pin MDK, allows the driver to

be used for other types of laser diode configuration; alternatively, it can be used as an analogue modulation

input (DC to a few kHz).

In the event of failure, such as overcurrent in the

laser path with a lack of feedback, for example, a

quick power lockout is activated. The shutdown continues until power is reapplied, permitting a restart.

The strain on power packs and batteries is relieved

and the laser class is retained even in the event of a

disturbance.

iC-WK offers additional protection by means of spike

detection at pin MDA. Should spikes or oscillation

occur at pin MDA the power lockout is activated.