A new high power laser diode has been developed and tested. The possibilities for driving high power laser diode bars and stacks at high frequencies have been shown. The driver is with 0.05% noise and ripples at DC, and can be modulated with 15 ns rise/fall times at 100A, with maximum frequency for square wave modulation up to 5 MHz. The spikes for the optical output at switching on/off are not exceeding 5%. The limitation of the used scheme with the existing commercial components allows frequencies up to 25 MHz and currents to 400A to be reached. The driver opens new applications for high rate data transmission at long range, fast scanning designators, materials processing, etc. with laser diodes with more than 100W output power, which will be discussed.