Can I use a 1.5ke18AC in place 1.5ke18A transzorb in a DC aplication?

[fjpompeo]

Hi,

Can I use an 1.5KE18AC in place of 1.5KE18A transzorb in a DC application? I mean, I need to protect a 14,4V car radio with a 10A series fuse but I already have only some 1.5KE18AC transzorb so was thinking in use this transzorb with a parallel schottcky diode so it's the same like a 1.5KE18A transzorb. Am I correct?

Thanks in advance,

Fernando

 

[ysba]

Actually the "AC" end part is a bidirectional device. The "A" end part is a uni-directional device, like a diode. The disadvantage in using the AC one is that bi-direcitonal devices usually have larger reverse leakage current than the uni-directional ones. How much is this current larger you should see at the datasheet. I think this is not a issue for your case.

The parallel diode will protect your circuit from reverse battery's polarity.

 

[D.A.(Tony)Stewart]

Hi,

Can I use an 1.5KE18AC in place of 1.5KE18A transzorb in a DC application? I mean, I need to protect a 14,4V car radio with a 10A series fuse but I already have only some 1.5KE18AC transzorb so was thinking in use this transzorb with a parallel schottcky diode so it's the same like a 1.5KE18A transzorb. Am I correct?

Thanks in advance,

Fernando

For automotive protection from load dump and reverse voltage error ( battery charge connect) the Transorb max clamp voltage will be 50% higher than Vbr rating so 18V clamps at 27V. Reverse leakage >10V is only 5uA.

Specs are usually +48 to -24V transients with so many Joules. I recall designing/building a dump simulator for production design test verification, but forgot some details.

For Reverse voltage protection consider 10A PTC series and with reverse diode or forward power Schottky diode.