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DLP4710: Using external illumination, external 3.3V for VCC_INTF, no need for 2.5V (?)

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Replies: 8

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Part Number: DLP4710

I have some questions about the DLPA3005 as used in a DLP4710+ 2X DLPC3439 design.  There's a schematic image below.

1. I will be using external illumination sources and timing circuitry (no color wheel, I just need 1-bit patterns sent to the DMD with no challenging timing requirements), so I don't need any illumination-related function from the DLPA3005: can I NC all the illumination-related pins as shown in the schematic below without causing issues?

2. I don't need a 2.5V source (e.g., PWR3_OUT DLP4710EVM eval board design): can I NC the PWR3-related pins as shown in the schematic below without causing issues?

3. I have an external 3.3V supply from the host that I had planned on using for VCC_INTF of the two DLPC3439 controller chips so I don't need to use any output of the DLPA3005 for this (e.g., PWR4_OUT as used in the DLP4710EVM eval board design): can I NC the PWR4-related pins as shown in the schematic below without causing issues?

3a. This external 3.3V source will be on "all the time" with respect to the DMD-related ICs (even when, for example, PROJ_ON from the host is low): will this cause issues?

3c. I can use the DLPA3005A PWR4 for the VCC_INTF is that makes this lower risk, it's just the minor additional components and complexity I am trying to avoid.

Thanks.