8.4.2.2 Single Block Phased Mode

Single Block Phased Mode is best described as "phasing" the data load operation with the Block Reset operation. The major advantages of Phased Modes (Single, Dual, and Quad) in general are the idea of not having to wait for the micromirror settling time duration to complete prior to the next block reset, and for not having to wait for the Reset Request to complete prior to loading more data. In the example of Figure 15, Block 15 is loaded with data while the Reset operation is taking place for Block 14 (Rst 14). The Reset Request (BLKMD and BLK_AD) for Block 14 needs to be one row cycle in duration minimum but can be extended to additional row cycles. Subsequent row cycles containing a valid Reset Request will be ignored until RST_ACTIVE goes low. Therefore, BLKMD and BLK_AD should transition from a Reset Request to a Block No-Op while RST_ACTIVE is still asserted as once RST_ACTIVE de-asserts there is the likelihood of an undesired Reset Request to be generated on the same block.

In Figure 15, Block 0 is issued a Block Reset concurrently with data being loaded into the next block (1). The Row Cycles of the Block 1 data loading capture the Reset Request for Block 0, and provide continued Row Cycles for the duration of both the Block Load and the Block Reset. Note that the loading of block 1 does not need to wait for the mirror settling time of Block 0. This is repeated until the last block is Reset (which might also contain loading the next Block 0 data). Since the DLP650LNIR block load time is already longer than the RST_ACTIVE time, full utilization of its bandwidth is readily achieved in a single block phased mode.

Figure 15. Single Block Phased Mode with Longer Block Load Times

Depending on the DMD type, the RST_ACTIVE duration of 4.5us may be longer than a single block load time. For example, the sequence shown inFigure 16 shows that when the Block Load time is shorter than RST_ACTIVE, one should include Row No-Ops to create a delay until the current RST_ACTIVE transitions low. Once RST_ACTIVE transitions low, the first row cycle of the next block data load can occur while also providing the Reset Request for the previously loaded block. At least one row cycle minimum must be completed to initiate the Reset Request and the next Reset Request must wait until the data is loaded and RST_ACTIVE transitions low.

Figure 16. Single Block Phased Mode with Short Block Load TImes

Figure 17 is nearly the same as Figure 16 except that the data loading of each block is timed such that it completes loading the block just about the same time the RST_ACTIVE signal goes low. Row No-Op cycles are used to provide the Reset Requests instead of data load row cycles. The benefit of this would be the delayed loading of data could provide more time for the customer application data processing upstream. In both cases, the next block Reset Request cannot be initiated until the previous Reset Request has completed.

Figure 17. 2nd Single Block Phased Mode with Short Block Load TImes