What is the difference between these 2? Is there any benefit of using one over the other? what value should the resistor on pin 2 be?
Also, can i short pin 7 and 6 given i dont need current sense? the datasheet dictates a minimum of 250mV and max 350mV, does it matter? Is this a function that is absolutely necessary for the ic's operation?
You don't need the current sense.
EDIT: I am not sure if the previous is clear. You don't have to use the current sensing, it is OK to short the pins together.
Smajdalf:
You don't need the current sense.
EDIT: I am not sure if the previous is clear. You don't have to use the current sensing, it is OK to short the pins together.
I was concerned because the datasheet mentioned a minimum voltage, but i shorted the pins none the less.
Its says see note 8, which explains it:
- If the output switch is driven into hard saturation (non−Darlington configuration) at low switch currents
(≤ 300 mA) and high driver currents (≥30 mA), it may take up to 2.0 μs to come out of saturation.
This condition will shorten the off time at frequencies ≥ 30 kHz, and is magnified at high temperatures.
This condition does not occur with a Darlington configuration, since the output switch cannot saturate.
If a non−Darlington configuration is used, the following output drive condition is recommended
Basically with the tapped inductor you can allow the external device to saturate (more efficient
on-voltage for the switch), but this is going to limit the switching speed as coming out of saturation
takes longer due to stored change effects.