Transistor KSP44 with Ic(max) 300mA can I use it for 150mA
Remember that a Bipolar Junction Transistor is an amplifier.

By feeding the Base a current, it allows 40-200x more current to flow from Collector to Emitter (see hFE, Current Gain Characteristic).

To enable this amplification, you must saturate the Collector-Emitter field (Vce) and the Base-Emitter field (Vbe). Looking at the datasheet, we can see a potential difference of 0.75V is needed across the Collector to the Emitter, and also 0.75V across the Base and Emitter. The column labelled "Test Conditions" isn't useful for you.

Now, looking at Figure 1 of the datasheet, 150mA Collector current sets the DC Current Gain (hFE) at around 70x. 

150mA / 70 = 2.1428mA is needed at the Base (at 10v Vce).