Connect DSP?microcontroller directly to IRS2101 - It is safe?

[sei]

Hi,

Is it safe to connect DSP/Microcontroller directly to High & Low Side Driver, IRS2101 (for driving PWM)? The IRS2101 will be driving the IRF840 Mosfet power switch. Usually, the literature on the internet shows a lot of people will use an optocoupler between a DSP/microcontroller and a high & low side driver. The optocoupler switching speed is slower, this is annoying.

In my point of view, WE CAN CONNECT DIRECTLY FROM DSP/MICROCONTROLLER TO HIGH & LOW SIDE DRIVER.

My reason:
1) The mosfet switching (IRF840), allows high current to flow from Drain (D) to Source (S) only. Your Get (G) is safe - protection no.1
2) If the mosfet switch breakdown, worst case scenario, the IRS2101 will protect from back current whatsoever into the DSP/Microcontroller - protection no. 2

What is your opinion? Any bad experience you want to share? :???:

 

[alexan_e]

I don't see a problem to connect them directly assuming that the output voltage level of your DSP/mcu in high enough, the input transition levels for LOW are <0.8v and for HIGH >2.5v.
The datasheet says that the input bias for high/low levels are just 5-10uA so you could also add resistors between the IRS chip and DSP/mcu

Alex