MSP-EXP432E401Y: Does one need to current limit VREFA+ (pin 9) when using an external VREF?

Daniel Nanto

Part Number: MSP-EXP432E401Y
Other Parts Discussed in Thread: REF2033, MSP432E401Y,

Good evening, I hope all is well!

I am working on a circuit, and I have run into a question. I am using the REF2033 to create a reference voltage of +1.65V, and will be linking VREF (pin 5) of the REF2033 to VREFA+ (pin 9) of the MSP432E401Y. In the MSP432E401Y's datasheet, §5.15.11 Table 5-33 mentions a typical input current of 330.5μF. Do I need to current limit this input pin?

In the MSP-EXP432E401Y, R41 (0Ω) is attached between 3V3 and VREFA+. Is this some sort of a current limiting resistor or just a 0R jumper?

Thank you for your help and patience,

Dan

11 months ago

+1 Charles Tsai 11 months ago

TI__Guru**** 160015 points

Daniel Nanto said:
the REF2033 to VREFA+ (pin 9) of the MSP432E401Y. In the MSP432E401Y's datasheet, §5.15.11 Table 5-33 mentions a typical input current of 330.5μF. Do I need to current limit this input pin?

Yes, please make sure the current does not exceed the datasheet max value.

This paper will be also useful. https://www.ti.com/lit/slyc147

Daniel Nanto said:
In the MSP-EXP432E401Y, R41 (0Ω) is attached between 3V3 and VREFA+. Is this some sort of a current limiting resistor or just a 0R jumper?

I think this is a 0R jumper. In this LaunchPad, VREF does not have a dedicated reference source but rather tie to VDDA and VDD for simplicity.

0 Daniel Nanto 11 months ago in reply to Charles Tsai

Prodigy 250 points

This is incredibly helpful, thank you!

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MSP-EXP432E401Y: Does one need to current limit VREFA+ (pin 9) when using an external VREF?