D-31M Datasheet, PDF (7/7 Pages) Roithner LaserTechnik GmbH – Driver for MID-IR LEDs

The single-shot multivibrator M generates voltage impulses with the adjustable fixed duration
synchronously with rise-up portion of input voltage impulses. Switching of duration of impulses is
carried out by means of switch SW1 in the range from 0,6 to 20 µс.
The multiplexer MX1 by means of the button “Operating mode” switch the clock pulses on the input
of voltage-to-current converter U/I. In addition clock pulses come to the jack “Synchro” for
synchronisation with the external photoreception amplifier.
The IR-light-emitting diode LED recive a pulse current from U/I converter. Start-up of circuit U/I is
carried out by means of the button “On/off”. The green light-emitting diode “Working” lights up in
that case . If the circuit of the LED is broken the light-emitting diode “Break” lights up. Adjustment
of the amplitude of the LED pulse current is implemented by means of a multiposition switch SW2.
The DC / DC circuit is a voltage converter from + 12 V in + 5 V, -5 V for power supply of all the
elements of the D-31M. The input voltage of DC / DC converter supplies from “+12 VDC” jack.
Synchronization
Single-shot
multivibrator M
Multiplexer
МХ1
Voltage-to-current
converter U/I
LED
Sw1
Pulse duration
Pulse
generator
Frequensy
0,5 2 4 8 kHz
Pulse/QCW
Working/Break On/Off
Current
Sw2
+12V
+5V
-5V
DC/DC
GND
Fig.10. The block diagram of D-31M.
09.07.2012
D-31M
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