imx.233 VDDIO_DRAM

[cnguyenterasci]

Hi guys,

I'm running the imx233 chip but have problems with the 2.5V VDDIO_DRAM.  All the other voltages are there (5Vsupply, 3.3V, 1.8V, 1.2V) except 2.5V for my DDR memory.  Is there something I need to do to enable the 2.5V regulator output on the IMX 233 chip?

[AnsonHuang · Accepted solution]

Hi, Calvin

     You may need to enable this 2P5 regulator manually, as it is disable by default. See below code:

    // DDR1,VDDM = 2.5V

        // Clear pulldown as it isn't needed for internal linear regulator

        HW_POWER_VDDMEMCTRL_CLR(BM_POWER_VDDMEMCTRL_PULLDOWN_ACTIVE);

        HW_POWER_VDDMEMCTRL.B.TRG = 0x10; // ~2.5v

        HW_POWER_VDDMEMCTRL_SET(BM_POWER_VDDMEMCTRL_ENABLE_ILIMIT);

        HW_POWER_VDDMEMCTRL_SET(BM_POWER_VDDMEMCTRL_ENABLE_LINREG);

        // Wait 10ms for 2p5 capacitor to fully charge

        XLDRStall(20000);

        HW_POWER_VDDMEMCTRL_CLR(BM_POWER_VDDMEMCTRL_ENABLE_ILIMIT);