ASEK37612-BUSBAR chip

I have an ASEK37612-BUSBAR evaluation board. The data sheet only shows the available IC’s and does not say which is on the eval board (page 2). The BOM on page 18 just says 37612. The only hint is figure 21 on page 14, which shows a 3.3V device, but that does not have the same busbar as the eval kit. Looking at the chip, the very faint marking is 612 with 2250, which looks like a YYWW date code.
I really need the voltage before smoking anything or getting unreliable data.


I can understand the confusion. It looks like there’s one board variant offered with a busbar configuration, and 3 for current-through-PCB applications, with differing copper widths under the part, if I’m reading correctly.

The datasheet doesn’t distinguish between 3 and 5v variants in the abs max table; on that basis there should be no smoke even if you put 5v to a 3v part, though the numbers may go a bit wonky if operating outside the range for which the part was trimmed. Watching the (unloaded) supply current as you turn up Vcc may offer a clue as to which chip is populated.

Plugging the numbers for the bus bar they sent you into the calculator software ought to give you an idea of what analog output a person could expect for a known current. The difference between 5/10/15 mv/g is pretty substantial, and ought to give you another point of inference.

I offer the above as suggestions in case you’re feeling impatient. I’ll put a request in for clarification, along with a suggestion that the documentation be updated to speak to the point.

Hi Rick,

Thanks for the response. I would appreciate knowing the part number rather than guessing. The actual calculator software is not what they have in the illustration. It defaults to one set of values for the ACS37612 rather than the selection shown in the data sheet.


After reading through various documentation on this part, I’d place money on that Allegro only manufactures one version of this part and then programs its EPROM to configure its characteristics to match the various part number options. This would explain why the 3.3V part can handle same absolute max voltage as the 5V part, and it would explain why there is only one part marking despite multiple variations of part numbers.

Hopefully we’ll have an answer back soon as to which one is in that board.

Figuring that Allegro might not know (did the guy/gal who set this up leave 2 years ago?), I made some measurements. This appears to work as a 5V, bi-directional, 10 mV/G chip.
Thanks to Digi-Key for responding.