DRV200-A-400
Low: 320 mA
High: 480 mA
Influence of cable length
The DRV200 offers high modulation bandwidth and some care must be taken when connecting the laser diode to the
driver for optimal performance. As a guideline, we measured the modulation response for various length of cable
between the driver and a DFB laser in TO can.
The response is measured using a DRV200-A-200 with a modulation gain set to M and a modulation signal of 500
mV
pp
. The cable is a pair of 22 AWG wires (0.644 mm diameter). The cable length is the length of a single wire. The
wire is always twisted except for the yellow curve.
We see that for twisted wires the peaking in the response increases slightly with the cable length, but it stays bellow 1
dB up to a length of 40 cm. However when the cable is not twisted peaking increases to more than 5 dB.
For optimal modulation performance use a twisted pair of wires with length as short as possible. The exact
modulation response depends also on the laser diode that is used.
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DRV200
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