I’d like to use the WLD3343 Driver and WLD3393 Demo Board to modulate a laser in constant power mode. Do I need any additional or external circuitry?
If you use those two components together to drive a laser in constant power mode, the only additional equipment you will need to modulate the laser is a source for the modulation signal (ie. function generator).
The maximum modulation bandwidth in constant power mode is about 1 MHz, but it will also be determined by the bandwidth of the photodiode in the laser.