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MicroZed Rev C docs

Former Member

Are the design docs (schematics, BOM, layout, mechanical) for MicroZed Rev C available?


I'm working on power sequencing for a MicroZed carrier. The current schematics (rev B) don't match the user guide description of the VCCIO_EN signal. The user guide says JX2.10 = VCCIO_EN; the rev B schematics show JX2.10 = PROGRAM#. The user guide also doesn't specify what voltage VCCIO_EN is pulled to for rev C (it says 3.3v for rev B, but I can't find this signal in the rev B schematics).

  • 0

    You should not bring up your PL Vcco supplies on your Carrier prior to Vccint and Vccaux being up and stable. Vccio_en is intended to be used as the enable signal from the MicroZed to the Carrier for the Carrier to use as an input to the PL Vcco supplies.

     

    On Rev B, this was shared with the PROG_B signal, which was pulled up to 3.3V. On Rev C, we decided to use the Power Good output from the 1.8V (Vccaux/Vccpaux) regulator as this allows the Carrier to start enabling the PL Vcco supplies at the earliest possible time.

     

    We are working to have the MicroZed Rev C documentation posted within a week. We have also been actively debugging an issue on the I/O Carrier, which has delayed the release of those documents, Hopefully we will have those posted with ~2 weeks.

     

    Bryan

  • 0 in reply to bhfletcher

    Thanks Bryan.

    Just to confirm- what voltage does rev C pull VCCIO_EN (the net tied to JX2.10) up to? It seems the TLV62130 PG output could handle a 3.3v pullup to mimic the rev B VCCIO_EN levels. But I'm guessing rev C uses the same circuit for PG_1V8 as rev B, giving a 1.8v logic high for the carrier's use of VCCIO_EN.

  • 0 in reply to Former Member

    PG_1V8 is pulled up to 1.8V. At the time 1.8V goes good, the only voltages available are Vin (5V or 12V), 1.0V, or 1.8V. We thought 1.8V was the best of those choices, but you may find your desired Vcco regulator needs >1.8V to enable. In that case, you could use a level translator.

    Bryan