iC-HB

TRIPLE 155 MHz LASER SWITCH

Rev A4, Page 2/8

DESCRIPTION

Triple Laser Switch iC-HB enables the spike-free

switching of laser diodes with well-defined current

pulses at frequencies ranging from DC to 155 MHz.

The diode current is determined by the voltages at

pins CIx.

The three fast switches are controlled independently

via LVDS/TTL inputs. Input TTL = hi selects TTL type

inputs. The laser diode can thus be turned on and off

or switched between different current levels (LDKx

connected) defined by the voltages at CI1, CI2 and

CIB. Channel B is preferably used for biasing.

For current monitoring purpose IMON sinks a fraction

of the sum of currents into LDKx:

I(IMON) =

92

+

75

Each channel can be operated at 65 mA DC (chan-

nel B: 60 mA) and up to 300 mA (channel B: 275 mA)

pulsed current depending on the frequency, duty cy-

cle and heat dissipation.

The integrated thermal shutdown feature protects the

IC from damage by excessive temperature.

PACKAGING INFORMATION QFN24 to JEDEC

PIN CONFIGURATION QFN24 4 mm x 4 mm

7

8

9

10

11

1

2

3

4

5

13

14

15

21

22

6

12

16

17

19

20

18

23

24

HB

code...

...

PIN FUNCTIONS

No. Name

Function

1 AGND2 Analogue ground channel 2

2 LDK2

Laser diode cathode channel 2

3 LDKB

Laser diode cathode channel B

4 AGNDB Analogue ground channel B

5 LDK1

Laser diode cathode channel 1

6 AGND1 Analogue ground channel 1

PIN FUNCTIONS

No. Name Function

7 EP1

Positive LVDS/TTL switching input chan-

nel 1

8 EN1

Negative LVDS switching input channel 1

9 SYN1 Sync output channel 1

10 VTTL Sync TTL output supply voltage

11 SYNB Sync output channel B

12 CI1

Current control voltage channel 1

13 ENB

Negative LVDS switching input channel

B

14 EPB

Positive LVDS/TTL switching input chan-

nel B

15 VDD

+5 V supply voltage

16 GND

Ground

17 CIB

Current control voltage channel B

18 IMON Laser diode current monitor output

19 CI2

Current control voltage channel 2

20 NER

Temperature shutdown monitor output

21 TTL

TTL inputs selector (EPx)

22 SYN2 Sync output channel 2

23 EN2

Negative LVDS switching input channel 2

24 EP2

Positive LVDS/TTL switching input chan-

nel 2

For improved heat dissipation the thermal pad is to be connected to a ground plane on the PCB.

Only pin 1 marking on top or bottom defines the package orientation (

HB label and coding is subject

to change).