i have a car JBL monoblock amp. and the power supply is build from IRF540. and i have new IRFZ44.
can i put IRFZ44 in place the not good IRFZ44.
úîéø
can i put IRFZ44 in place the not good IRFZ44.
úîéø
Obviously you already have the Z44, and in the time it took
you to pose the question you could have soldered it in and told
us about what happened, and then we'd all really know. 😉
you to pose the question you could have soldered it in and told
us about what happened, and then we'd all really know. 😉
The IRFZ44 is 60V, and 50amp @25 degrees C and the IRF540 is 100V and 28amp @25 degrees C. Hope that helps in some way.
Regards
Bowdown
Regards
Bowdown
Are you sure those IRF540s are part of the power supply?
IRFZ44 has lower input capacitance [no need to change gate drive], similar output capacitance [no need to change RC damping networks] and much lower Rds-on so it will be a great replacement for IRF540 in any 12V push-pull SMPS
Anyway, all car-audio amplifiers I've seen using IRF540 for SMPS were essentially worthless. Apparently those amplifier designs had undergone so extreme cost reduction processes that manufacturers didn't hesitate to save some more cents of dollar by using IRF540 instead of IRFZ34 or IRFZ44 on the SMPS
[JBL has been applying severe cost and quality reduction policies to its car audio market for some years]
IRFZ44 has lower input capacitance [no need to change gate drive], similar output capacitance [no need to change RC damping networks] and much lower Rds-on so it will be a great replacement for IRF540 in any 12V push-pull SMPS
Anyway, all car-audio amplifiers I've seen using IRF540 for SMPS were essentially worthless. Apparently those amplifier designs had undergone so extreme cost reduction processes that manufacturers didn't hesitate to save some more cents of dollar by using IRF540 instead of IRFZ34 or IRFZ44 on the SMPS
[JBL has been applying severe cost and quality reduction policies to its car audio market for some years]
Don't do it, it is quite pointles work, nothing will be change 🙁 . Save up time ( better is spend it with your girlfriend 😎 ).
OOOooo......
it is a secend time that i fix the power supply...
OK so i will buy a new IRF540.... (8)
it is a secend time that i fix the power supply...
OK so i will buy a new IRF540.... (8)
<OK so i will buy a new IRF540.... >
No way! "better is spend it with your girlfriend "
I fully agree Eva's opinion, exclude the cost comparison - irfz44 cheaper then irf540, and the irf540n cost close to irf3205 even, which 110A@25c 55V! 😎
No way! "better is spend it with your girlfriend "
I fully agree Eva's opinion, exclude the cost comparison - irfz44 cheaper then irf540, and the irf540n cost close to irf3205 even, which 110A@25c 55V! 😎
Result with both types will be the same, so use cheaper ones 😉 - Eva, if is driving stage designed for higher input capacity ( what certainly is ), is lower capacity of new ones for nothing !
Oh, IRFxx prices vary a lot over time and depending on the quantity and procedence of the devices, but as an exmaple, when some chinese car amplifier manufacturer has 10.000 IRF540 in stock and there is no demand for MOSFET output stages it's allways cheaper to use them for SMPS than to buy another 10.000 IRFZ34 or IRFZ44 and eat the 10.000 IRF540 with potato chips 😀
Interesting post Eva as always. It is interesting that you say that all car amps which have the IRF540 are worthless. Can you please explain why? Does the high Rds ON resistance affect the sound quality or is it just an efficiency issue. I recently built a car amplifier using a pushpull converter plus 2 x LM3875 for stereo operation. I used 4 x IRF540 (2 on each side) as the switching mosfets and the sound was not the same as running it from the toroidal. It was as if there was something missing. It lacked vitality. Lets see what you have to say about this.
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