2011666 - LASER COMPONENTS - Datasheet.Directory

iC-WKN

15V CW LASER DIODE DRIVER

Rev B1, Page 1/9

FEATURES

♦CW operation up to 300mA from 2.4 to 15V supply voltage

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

♦Optimised for N-type laser diodes

♦Simple output power adjustment via an external resistor (APC)

♦Power control loop accuracy better than 1.5% 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 2.5µA to 6.25mA

♦Pin compatible to iC-WK and iC-WKL (SO8 package)

APPLICATIONS

♦Blue laser diodes

♦LD modules

PACKAGES

SO8tp DFN10

4mmx4mm

(on request)

BLOCK DIAGRAM

MD LD

0.5 V

VREF

..47 nF..

OVERTEMP.

TRANSIENT

iC−WKN

OVERCURRENT

..100 nF..

..1 uF..

CLDA

AGND

CVCC

LDK

MDK

MDA

LDA

GND

VCC

+2.4..+15 V

PROTECTION

−

FEEDBACK MON.

0.08..200 k Ω47 pF

suitable laser diode configurations: N, P, M

iC-WKN

15V CW LASER DIODE DRIVER

Rev B1, Page 2/9

DESCRIPTION

iC-WKN is a driver for laser diodes in continuous

wave operation with laser currents of up to 300mA,

which requires only four external components. The

wide power supply range of up to 15V allows for op-

eration of blue laser diodes.

The iC includes integrated circuitry protecting against

destruction by ESD, excessive temperature and over-

current plus a soft start of the regulator to protect the

laser diode when the power supply is switched on.

The iC also ﬁlters the laser diode power supply for

transients.

The regulator is adapted to the laser diode by an ex-

ternal resistor at MDA. The monitor current acts as

a reference and is regulated independent of the in-

ﬂuence of temperature and supply voltage (range:

2.5µA to 6.25mA). 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 analog modulation

input (DC to a few kHz).

In the event of failure, such as overcurrent in the laser

path due to a lack of feedback, for example, a quick

power lockout is activated. The shutdown persists

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 dis-

turbance.

iC-WKN offers additional protection by means of

spike detection at pin MDA. Should spikes or oscilla-

tion occur at pin MDA the power lockout is activated

after a certain time-out.

iC-WKN

15V CW LASER DIODE DRIVER

Rev B1, Page 3/9

PACKAGES SO8tp, DFN10 4mmx4mm to JEDEC standard

PIN CONFIGURATION SO8tp

(top view)

GND

MDK

AGND

MDA

LDA

WKN

VCC

LDK

code...

...

PIN FUNCTIONS

No. Name Function

1 GND Ground

2 CI Capacitance for Power Control

3 AGND Reference Ground for CI, RM

4 MDK Monitor Input 2

(MD Cathode, modulation)

5 MDA APC Setup, Monitor Input 1

(MD Anode)

6 VCC +2.4...+15V Supply Voltage

7 LDA Laser Supply (LD Anode)

8 LDK Driver Output (LD Cathode)

The Thermal Pad is to be connected to a Ground Plane on the PCB. Do not short-circuit pins AGND and

GND, for this may deteriorate the precision of the regulator and interfere with the soft-start!

PIN CONFIGURATION DFN10 4mmx4mm

(top view)

4 7

...

...yyww

iC−WKN

PIN FUNCTIONS

No. Name Function

1 GND Ground

2 CI Capacitance for Power Control

3 AGND Reference Ground for CI, RM

4 MDK Monitor Input 2

(MD Cathode, modulation)

5 n.c.

6 MDA APC Setup, Monitor Input 1

(MD Anode)

7 n.c.

8 VCC +2.4...+15V Supply Voltage

9 LDA Laser Supply (LD Anode)

10 LDK Driver Output (LD Cathode)

The Thermal Pad is to be connected to a Ground Plane on the PCB. Do not short-circuit pins AGND and

GND, for this may deteriorate the precision of the regulator and interfere with the soft-start!

iC-WKN

15V CW LASER DIODE DRIVER

Rev B1, Page 4/9

ABSOLUTE MAXIMUM RATINGS

Beyond these values damage may occur; device operation is not guaranteed.

Item- Symbol Parameter Conditions Fig. Unit

No. Min. Max.

G001 VCC Voltage at VCC -6 16 V

G002 I(VCC) Current in VCC -10 900 mA

G003 I(CI) Current in CI -10 10 mA

G004 I(LDA) Current in LDA -900 10 mA

G005 I(LDK) Current in LDK -10 900 mA

G006 I(MDA) Current in MDA -10 10 mA

G007 I(MDK) Current in MDK -10 10 mA

G008 I(AGMD) Current in AGND -10 10 mA

G009 I(GND) Current in GND -900 10 mA

G010 Vd() ESD Susceptibility at all pins MIL-STD-883, Method 3015, HBM

100pF discharged through 1.5kΩ

2 kV

G011 Tj Operating Junction Temperature -40 150 °C

G012 Tj Storage Temperature Range -40 150 °C

THERMAL DATA

Operating Conditions: VCC = 2.4...15V

Item- Symbol Parameter Conditions Fig. Unit

No. Min. Typ. Max.

T01 Ta Operating Ambient Temperature Range -40 85 °C

T02 Rthja Thermal Resistance Chip/Ambient soldered to PCB;

no additional cooling areas 170 k/W

therm. pad soldered to approx. 2cm²

cooling area 30 50 k/W

All voltages are referenced to ground unless otherwise noted.

All currents into the device pins are positive; all currents out of the device pins are negative.

iC-WKN

15V CW LASER DIODE DRIVER

Rev B1, Page 5/9

ELECTRICAL CHARACTERISTIC

Operating Conditions: VCC = 2.4...15V, RM = 80Ω...200kΩ, Tj = -40...125°C unless otherwise noted

Item- Symbol Parameter Conditions Tj Fig. Unit

No. °C Min. Typ. Max.

Total Device

001 VCC Permissible Supply Voltage 2.4 15 V

002 I(LDK)m Permissible Laser Drive Current power control range 10 300 mA

003 Idc(VCC) Supply Current without load path closed control loop, I(MDK) = 0,

I(LDK) = 290mA 10 20 mA

004 Ioff(VCC) Supply Current on Reset 2.4 5 mA

005 Ir(VCC) Reverse Supply Current RM = 50kΩ, VCC = -6V -6 -3 mA

006 ton() Turn-on Delay VCC: 0 →5V to 95% I(LDK),

I(LDK) = I(LDK)m;

CI = 47 nF 70 µs

CI = 100 nF 150 µs

007 Vc()hi Clamp Voltage hi at VCC, LDA I()= 10mA, other pins open 16 24 V

008 Vc()hi Clamp Voltage hi at LDK V() < VCC + 1 V; I() = 10mA,

other pins open 16 24 V

009 Vc()hi Clamp Voltage hi at MDK vs. LDA I() = 10mA, other pins open 8 11 V

010 Vc()hi Clamp Voltage hi at MDA, CI I() = 10mA, other pins open 1.1 4 V

011 Vc()lo Clamp Voltage lo at VCC, LDA,

MDK, MDA, CI I() = -10mA, other pins open -9 V

Reference and Monitor Inputs MDA, MDK, AGND

101 V(MDA) Reference Voltage at MDA closed control loop,

V(LDK) > Vs(LDK) 480 500 520 mV

102 dV(MDA) Reference Voltage Temperature

Drift at MDA see 101 120 µV/°C

103 Ierr(MDA) Input Current in MDA closed control loop, I(MDK) = 0,

I(LDK) = 10...290mA -100 100 nA

104 dI(MDA) Input Current Temperature Drift in

MDA see 103 -1 1 nA/°C

105 APCerr Control Error RM = 10kΩ, Tj = 0...80°C 0.3 %

RM = 10kΩ, Tj = -40...125°C 1 %

106 dI(RM) Supply Voltage Suppression V(VCC): 2.4 →15V,

I(LDK) = 290mA -1.5 1.5 %

107 Rgnd() Resistor AGND-GND 3 Ω

108 Vf(MDK) Voltage at MDK Vf() = V(LDA) - V(MDK),

I(MDK) = 1µA...1mA 0.46 2 V

109 CR() Current Ratio I(MDA)/I(MDK) I(MDK) = 1µA...1mA 0.98 1.02

I(MDK) = 1..6mA 0.95 1.05

110 TC() Current Ratio Temperature

Coefﬁcient I(MDA)/I(MDK) I(MDK) = 1µA...1mA -0.005 0.005 %/°C

I(MDK) = 1...6mA -0.025 0.025 %/°C

Laser Driver LDA, LDK

201 Vs(LDK) Saturation Voltage at LDK I(LDK) = 40mA 350 mV

I(LDK) = 290mA 700 mV

202 dI(LD) Load Balancing Error I(LD) = 20mA,

I(LDK): 20mA →290mA -1.5 1.5 %

203 It(LDK) Overcurrent Threshold in LDK V(LDK) = 2...5.5V 300 700 mA

204 It(LDK)m Maximum Overcurrent Threshold

in LDK 1.2 A

205 toff() Overcurrent Reset Delay lack of feedback:

I(MD) = 0 to I(LDK) = It(LDK);

CI = 47nF 85 µs

CI = 100nF 170 µs

206 Vf() Flyback Diode Forward Voltage

LDK-LDA I(LDK) < 290mA 1.3 V

207 Rvcc() Transient Protection Resistor VCC to LDA 1.3 Ω

208 Vt(MDA) Shutdown Threshold at MDA t > 1µs 0.7 2 V

iC-WKN

15V CW LASER DIODE DRIVER

Rev B1, Page 6/9

ELECTRICAL CHARACTERISTIC

Operating Conditions: VCC = 2.4...15V, RM = 80Ω...200kΩ, Tj = -40...125°C unless otherwise noted

Item- Symbol Parameter Conditions Tj Fig. Unit

No. °C Min. Typ. Max.

Control Release Flip-Flop

401 VCCen Set Threshold for Enable

Flip-Flop 0.6 1.9 V

-40 1.2 1.9 V

27 1.0 1.7 V

125 0.6 1.2 V

402 Toff Overtemperature Shutdown 140 165 °C

iC-WKN

15V CW LASER DIODE DRIVER

Rev B1, Page 7/9

SAFETY PRECAUTIONS

Laser light can damage the human eye and the

eyes of animals. Do not look at any laser light di-

rectly or through any optical lens. When handling a

laser diode, do not look directly at the light generated

by it. Wear appropriate safety glasses to prevent light

from entering the eye even by reﬂection.

FUNCTION DESCRIPTION

Turn-on behaviour

After switching the supply voltage on, the output stage

remains disabled until the internal enabling ﬂip-ﬂop is

set by a sufﬁciently high voltage at LDA.

I(LDK)

20 m

40 m

60 m

V(CI)

500 mV

1 V

V(MDA)

100 mV

200 mV

300 mV

400 mV

V(LDA)

1 V

2 V

3 V

4 V

5 V

V(VCC)

1 V

2 V

3 V

4 V

5 V

0 10 us 20 us 30 us 40 us 50 us

Time

Phase I Phase II Phase III

Figure 1: Turn-on behaviour

A quick soft-start follows during phase I; the control

capacitor CI is charged at an accelerated rate until the

voltage at pin MDA reaches 1/3 of its nominal value.

With V(MDA)>1/3V(MDA)nom phase II starts, the

controlled start-up. The transition to CW operation

(phase III) is gradual and primarily determined by the

values of CI and RM. CI is properly dimensioned when

the voltage overshoot at MDA is at a minimum.

Turn-off behaviour

iC-WKN works without a ﬁxed undervoltage lockout,

thus the laser diode forward voltage is the prime fac-

tor determining the lowest possible supply voltage.

If the voltage drops below this value, the output driver

is forcibly saturated and the laser current decreases.

iC-WKN simultaneously discharges the control capac-

itor CI so that no excessive laser diode currents occur

when the supply voltage rises again.

I(LDK)

20 m

40 m

60 m

V(CI)

500 mV

1 V

V(MDA)

100 mV

200 mV

300 mV

400 mV

V(LDA)

1 V

2 V

3 V

4 V

5 V

V(VCC)

1 V

2 V

3 V

4 V

5 V

100 us 110 us 120 us 130 us 140 us 150 us 160 us

Time

Phase IV Phase V

Figure 2: Turn-off behaviour

Disruptions in operation

The power control is shut down with excessive driver

temperature or when the laser current reaches the

overcurrent shutdown threshold, for example when the

feedback is interrupted. If the monitor diode or the

bias resistor RM fail, the device is shut down in less

than 250µs, provided that the supply voltage applied

is high enough. When modulating the laser current via

pin MDK, excessive voltage occurring at pin MDA also

may cause a shutdown.

iC-WKN

15V CW LASER DIODE DRIVER

Rev B1, Page 8/9

APPLICATION NOTES

Setting the output power

The output power is simply set by RM = V(MDA) /

I(MD); with V(MDA) = Item-No. 101 and I(MD) = mon-

itor current of the laser diode at the desired operating

point. RM should be combined from a ﬁxed resistor

(max. output power) and a trimmer (calibration).

Further application notes on the iC-WK family (iC-WK,

iC-WKL, iC-WKN) and the data sheet of the demo

board are available as separate documents.

This speciﬁcation is for a newly developed product. iC-Haus therefore reserves the right to change or update, without notice, any information contained herein,

design and speciﬁcation; and to discontinue or limit production or distribution of any product versions. Please contact iC-Haus to ascertain the current data.

Copying – even as an excerpt – is only permitted with iC-Haus approval in writing and precise reference to source.

iC-Haus does not warrant the accuracy, completeness or timeliness of the speciﬁcation on this site and does not assume liability for any errors or omissions

in the materials. The data speciﬁed is intended solely for the purpose of product description. No representations or warranties, either express or implied, of

merchantability, ﬁtness for a particular purpose or of any other nature are made hereunder with respect to information/speciﬁcation or the products to which

information refers and no guarantee with respect to compliance to the intended use is given. In particular, this also applies to the stated possible applications or

areas of applications of the product.

iC-Haus conveys no patent, copyright, mask work right or other trade mark right to this product. iC-Haus assumes no liability for any patent and/or other trade

mark rights of a third party resulting from processing or handling of the product and/or any other use of the product.

iC-WKN

15V CW LASER DIODE DRIVER

Rev B1, Page 9/9

ORDERING INFORMATION

Type Package Order Designation

iC-WKN SO8tp iC-WKN SO8

DFN10 4mmx4mm iC-WKN DFN10

Demo Board WKN4D DEMO

For information about prices, terms of delivery, other packaging options etc. please contact:

iC-Haus GmbH Tel +49(6135)9292-0

Am Kuemmerling 18 Fax +49(6135)9292-192

D-55294 Bodenheim Web: http://www.ichaus.com

GERMANY E-Mail: sales@ichaus.com