DC/DC converter

[Kan]

Hi
Have trouble with the FX1S DC/DC converter IC. It is out of order because of overvoltage. It marked as I01 5212. No information on the net. Could you help with datasheet on it and analogous.

Thank you.

[Al_The_Man]

Is it maybe a 12v regulator IC if it is 12+ then it might be equivalent to a 7812. This is a DC in 12vdc out three terminal regulator IC, if it is for 12dc- then it would be 1 7912.
Al.

[Kan]

Al the Man,
Thank you for respond.

Sorry, I’ve forgotten to mention the IC has four terminals. The 1 is +24DC input, the 4 is ground (0 V), the 2 is the output? with diodes: 2 diodes connected to anodes and 1 diode – to its cathode. And the 3 terminal seems to be a loop back and connected via resistor of very small size (small current).
Sorry for being persist, I believe I can fix this FX1S PLC and have spare unite.

[mauriceduteau]

Usually a switcher chip will have at least 8 pins. I did a search at digikey and not much shows up under IC's. Send a photo of the chip & surroundnig parts and I will see if I can help out.

[NC Cams]

YOu might have a custom, "house numbered" IC - They might be stepping down 24 dc in to 12 or 5vdc out and are using a zener or some other form of preregulation followed up by a regular IC. Fanuc did a lot of this "custom chip" stuff so as to create a smaller package.

What is the input voltage and what output voltage are you ultimately trying to achieve??? How much current???

YOu might want to craft up a pregegulator to initially drop the volage to a lesser level using off the shelf regulators. National has a bunch of regs that will do this along with many application circuits in their vast array of voltage regulator chips.

NOTE: automotive grade regulators are designed for 60 volt spike resistance and can almost run at 24vdc forever - the generic 75xx's don't have this feature. They do this to protect the new computers from "hot shot" battery jumps that some service trucks still use for jump starting.

It is still better to preregulate so as to reduce heat dissipation if you have to step down from say 24 to 5vdc. The power has to go someplace and into heat it will go....

[Kan]

Hi,
Thank you all for response. I’ll try to contact the Mitsubishi for the information.