48V Based Application Question

Have a 48V nominal input voltage application and am wondering if you can help me decide whether I should use a PAC5523A device (with a 72V Abs Max) or a PAC5532B device (which is 160V Abs Max)? Appreciate any guidance you may offer!

Hi eBLDC, good question on 48V applications. The reality is we see both devices being employed with applications in which the input power sits at 48V nominal. Nonetheless, whether you will want to use any of the 72V based devices (such as the PAC5523 or PAC5524), or a PAC5532 will depend on what kind of voltage swings you can expect to experience while the motor is being driven. For example, certain battery based applications are pretty good at staying very close to the 48V mark, and since they hardly ever have incursions into the PAC5523’s 72V Abs Max, they can operate quite reliably.

We do see some other applications in which higher voltage swings are possible, in some cases getting too close to the 70V mark. For applications of this sort we highly recommend considering any of the PAC5x32 devices, as they will have plenty of headroom left even during the harshest of transient events.

One last note. The most I would ever recommend a PAC5523 to be operated at on battery based applications is 48V, assuming leaded acid batteries. If you are using Lithium Ion battery chemistries, and the nominal voltage is more like 50V to 56V, I definitely think you should only consider PAC5x32 devices as it would be very hard to ensure the PAC5523’s Abs Max is not abused. Luckily, our code projects contain code base for either PAC5523 or PAC5532 so with a single flip of a flag, the code reconstitutes itself so you do not need to worry about differences between each device. Hope the info helps!