This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

CSD95377Q4M: Compatible with UCD924x controllers?

Part Number: CSD95377Q4M
Other Parts Discussed in Thread: UCD9224E, UCD9246E, UCD9248E, UCD9222, UCD9244, UCD74120, UCD9246, UCD74111

Is CSD95377 easily compatible with UCD924x digital controllers?

It looks like they would match up well, I believe UCD924x.SRE pin would connect to the SKIP# pin of the CSD95377.

The literature for the UCD924x appears to be geared mostly around the UCD7xxx devices.

  • Hi,

    Yes, in principle CSD95377Q4M would be compatible with digital controllers from the UCD924x family.

    If you want the Zero Crossing comparator inside CSD95377 to be active, then you can drive the SKIP# pin straight from UCD924x SRE pin.

    If SKIP pin is driven High by SRE, then CSD95377Q4M will operate in forced CCM ( continuous Conduction Mode).

     For better Light Load efficiency , SR FET may be disabled by driving SKIP# low.

    Additionally, you can use SKIP# pin as an IC Disable by driving it inside the tri-state window.

    Best Regards.


  • I do not know of any examples of the CSD95377 being used with a UCD92xx controller but it appears that it could be compatible with the latest controller iterations which implement a feature that allows the PWM output to be tri-stated when the rail is disabled.

    I know the UCD9222 and the UCD9244 implement this feature by default as they do not have SRE pins and I know the UCD9224E and the UCD9246E/UCD9248E have an option to turn on this functionality.

    The E versions are not shown on the web but are fully released and in production and all supported by the Fusion GUI.

    I believe several of the non-E versions may also support this but I would need to dig into this to be sure.

    Most customers use the UCD92xx devices with the UCD7xxx drivers which do not require the tri-state PWM.

    The CSD95377 does not have any current sensing functionality built in as do the UCD7xxx drivers so you would lose the ability to monitor current and respond to current faults unless you could implement an external amp with DCR current sensing to replace that capability.

    How much current per phase would you need?

  • The design consists of an FPGA, DRAM, and a large flash Array.  FPGA core currents could be ~30A, but don't know for sure, which is why I'm considering a flexible solution.

    The CSD9x devices are compelling because they are small. 
    We may need more accurate current sensing so the DCR current sense method may not be sufficient. 
    We may have to use a sense resistor anyway.

    I am looking at the UCD74120, '74106, and '7242 devices.  They may be sufficient.

    Why are the 'E versions of the controllers not published?

  • The E version was a FW spin for a large telecom, I do not know why it was never rolled out to general market but it has been offered to other customers previously.
    If you need more than 25A then you could always set the UCD9246 to implement two phases for that rail with two UCD74111/120.