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LMKDB1102: LMKDB12xx and LMKDB11xx default OE1# value, pull-up or pull-down?

Part Number: LMKDB1102
Other Parts Discussed in Thread: LMKDB1202, LMKDB1204, LMKDB1104, LMKDB1108, LMKDB1120

Tool/software:

Hello!

I am looking at the LMKDB12xx and LMKDB11xx family (they share a datasheet), and I am confused about the default behavior of the OE# pins.

The following variants mention in their pin function tables an "Internal Pull-up resistor" on the OEx# pins:
- LMKDB1102
- LMKDB1202
- LMKDB1204
Screenshot from 1102 pin function table


The following variants mention in their pin function tables an "Internal Pull-down resistor" on the OEx# pins:
- LMKDB1104
- LMKDB1108
- LMKDB1120
Screenshot from 1104 pin function Table 5-3:

This is a little strange but not suspicious on its own. I became confused when I saw the LMKDB1x02 Evaluation Module user manual, where on page 4, table 3-3 it shows "Low" as the default input value.

So which is it for LMKDB1102 and the others that mentioned "Internal Pull-up resistors"? Is an external pull-down resistor required as the datasheet suggests, or is the default value "low" as the evaluation module suggests? Is there a typo in the datasheet or the evaluation module user manual or am I missing something?

Thanks!
- Zoltan

  • Oops, just saw something I missed.

    It seems to me that the "Low (default)" description in the evaluaiton module comes from the header jumper seen here.

    I would still appreciate an answer about the differences in pin function on LMKDB1102 vs. LMKDB1104, where it looks like I WOULD need to add a PD resistor on LMKDB1102, but NOT need one on LMKDB1104 in order to enable all outputs?

    Cheers!

    -Zoltan

  • Hi Zoltan, 
    The DS is correct. 
    There are some differences between the PU/PD values. 

    The LMKDB120x family have internal PUs due to being P2P with Renesas RC1920x family. 

    LMKDB1102 has an internal PU like Renesas RC1902. 

    Best regards, 

    Vicente