Hi all,
I'm trying to identify the component as per the attached photo.
It bears the marking 4946 (logo) AC (delta) T748, and it is a 8-pin SMD (SOP?) package.
I've already done extensive searching and my findings have narrowed down the possible choices to:
1) Maxim MAX4946
2) A 748 op-amp
Now, the second option is very likely wrong. The "748" is placed at the end of the marking, where usually is shown the manufacturing date a/o production batch. Moreover, the signals and supply routed to the 8 pads are not consistent with the functions of the respective chip pins as shown on the 748 datasheet.
The first option could be a good guess instead, since the device I'm trying to repair is showing a diagnostic error code indicating a fault on supply voltage, and the MAX4946 is designed for this precise purpose.
The doubts come from the logo shown on chip. It is not the MAXIM logo for sure, and as far as I know no other manufacturer has ever produced the 4946. Also the MAXIM datasheet shows that the only SMD package available for the 4946 is the 8uDFN, that's not my case. Moreover, the MAX4946 is almost impossible to find.
I don't have a schematic available for the device under repair (a servo drive) but I'm sure having identified the faulty component, since the voltage diagnosed as wrong is actually correct, and the fault itself is temperature-dependent. It comes on at the first power-up (device cold) and disappears after a minute or two of thermalization. I was even able to reproduce the fault by freezing / heating locally the would-be 4946 and every time the fault appeared when freezing and disappeared heating.
You can easily understand my frustration of seeing a "case solved" transform into "mission impossible" because the lack of a component
I apologize for the long post, I was just trying to provide as much info I could.
Any suggestion appreciated, thanks in advance.
I'm trying to identify the component as per the attached photo.
It bears the marking 4946 (logo) AC (delta) T748, and it is a 8-pin SMD (SOP?) package.
I've already done extensive searching and my findings have narrowed down the possible choices to:
1) Maxim MAX4946
2) A 748 op-amp
Now, the second option is very likely wrong. The "748" is placed at the end of the marking, where usually is shown the manufacturing date a/o production batch. Moreover, the signals and supply routed to the 8 pads are not consistent with the functions of the respective chip pins as shown on the 748 datasheet.
The first option could be a good guess instead, since the device I'm trying to repair is showing a diagnostic error code indicating a fault on supply voltage, and the MAX4946 is designed for this precise purpose.
The doubts come from the logo shown on chip. It is not the MAXIM logo for sure, and as far as I know no other manufacturer has ever produced the 4946. Also the MAXIM datasheet shows that the only SMD package available for the 4946 is the 8uDFN, that's not my case. Moreover, the MAX4946 is almost impossible to find.
I don't have a schematic available for the device under repair (a servo drive) but I'm sure having identified the faulty component, since the voltage diagnosed as wrong is actually correct, and the fault itself is temperature-dependent. It comes on at the first power-up (device cold) and disappears after a minute or two of thermalization. I was even able to reproduce the fault by freezing / heating locally the would-be 4946 and every time the fault appeared when freezing and disappeared heating.
You can easily understand my frustration of seeing a "case solved" transform into "mission impossible" because the lack of a component
I apologize for the long post, I was just trying to provide as much info I could.
Any suggestion appreciated, thanks in advance.
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