problem with l298n

[hamza_hamza11981]

Posted on July 14, 2009 at 16:08

problem with l298n

[hamza_hamza11981]

Posted on May 17, 2011 at 10:15

hi everybode

i have a problem with l298n ic at this moment i burn 5 pes of l298n i don no what is the problem can anyone help me motor current 0.5A MOTOR VOLTAGE 24

[hamza_hamza11981]

Posted on May 17, 2011 at 10:15

m using pwm at 500HZ or 2KH

AND the motor run at clockwise and ccw plz see attached scematic diagram :D

[enrico-dora-spa]

Posted on May 17, 2011 at 10:15

Hello hamza,

your application schematic seems ok. I think you control motor current varying PWM duty-cycle, are you sure that motor current never exceed device absolute limits? Are BR1 diodes of fast type? This is very important in order to correctly protect device. Regards Enrico POLI Motor control team

[hamza_hamza11981]

Posted on May 17, 2011 at 10:15

thanx for your reply

1-the max current is 0.5A(not more 0.5A) 2- the duty cycle at 100% 3-i m using usual bridge diode(selecon si) not sottky diode**** I read the data sheet they prefare to be sottky DOIDE 4- i have 3 motors and 3 h_bridge**(plz see real scematic diagram) and the three bridgs WAS burned THEN AA- is the capacitor (100nf) at Vs and Vss very impotant??? BB- can i add resistors to enable,and all inputs of the h bridge???

[enrico-dora-spa]

Posted on May 17, 2011 at 10:15

I think device failure can be due by a lack of protection. During motor current recirculation external diodes should quickly clamp output pin voltage, this is why shottky diodes, or in general ''fast'' diodes, are recommended.

AA- The 100nF capacitors on VS and VSS are very important too. Sorry if I do not noticed they are not present in your schematic. I suggest to add an electrolytic capacitor to VS too (about 100uF should be enough). BB- Sorry, but I not sure of the meaning of the question. Do you mean if you can pull-up L298 enable signals with a resistor instead to drive them through the micro? [ This message was edited by: enrico-dora-spa.poli on 14-07-2009 10:08 ]

[hamza_hamza11981]

Posted on May 17, 2011 at 10:15

thanx for your answer

i will do the changes and then tell you again thanx agian :D