ZHCSFE1B June 2016 – August 2017 ADS8920B , ADS8922B , ADS8924B
PRODUCTION DATA.
The device provides an option to transfer the data to the host controller at a single data rate (default, SDR) or at a double data rate (DDR). Set the DATA_RATE bit in the SDO_CNTL register to select the data transfer rate.
In SDR mode (DATA_RATE = 0b), the RVS pin toggles from low to high, and the output data bits are launched on the SDO pins on the output clock rising edge.
In DDR mode (DTA_RATE = 1b), the RVS pin toggles (from low-to-high or high-to-low), and the output data bits are launched on the SDO pins on every output clock edge, starting with the first rising edge.
The device supports all 24 combinations of output clock source, bus width, and output data rate, as shown in Table 9.
PROTOCOL | OUTPUT CLOCK SOURCE | BUS WIDTH | OUTPUT DATA RATE | SDI_CNTL | SDO_CNTL | #OUTPUT CLOCK (Optimal Read Frame) | TIMING DIAGRAM |
---|---|---|---|---|---|---|---|
SRC-EXT-SS | SCLK(1) | Single | SDR | 00h, 01h, 02h, or 03h(2) |
03h | 8 | Figure 75 |
SRC-INT-SS | INTCLK(3) | Single | SDR | 43h | 8 | Figure 76 | |
SRC-IB2-SS | INTCLK / 2(3) | Single | SDR | 83h | 8 | ||
SRC-IB4-SS | INTCLK / 4(3) | Single | SDR | C3h | 8 | ||
SRC-EXT-DS | SCLK(1) | Dual | SDR | 0Bh | 8 | Figure 79 | |
SRC-INT-DS | INTCLK(3) | Dual | SDR | 4Bh | 8 | Figure 80 | |
SRC-IB2-DS | INTCLK / 2(3) | Dual | SDR | 8Bh | 8 | ||
SRC-IB4-DS | INTCLK / 4(3) | Dual | SDR | CBh | 8 | ||
SRC-EXT-QS | SCLK(1) | Quad | SDR | 0Fh | 4 | Figure 83 | |
SRC-INT-QS | INTCLK(3) | Quad | SDR | 4Fh | 4 | Figure 84 | |
SRC-IB2-QS | INTCLK / 2(3) | Quad | SDR | 8Fh | 4 | ||
SRC-IB4-QS | INTCLK / 4(3) | Quad | SDR | CFh | 4 | ||
SRC-EXT-SD | SCLK(1) | Single | DDR | 13h | 8 | Figure 77 | |
SRC-INT-SD | INTCLK(3) | Single | DDR | 53h | 8 | Figure 78 | |
SRC-IB2-SD | INTCLK / 2(3) | Single | DDR | 93h | 8 | ||
SRC-IB4-SD | INTCLK / 4(3) | Single | DDR | D3h | 8 | ||
SRC-EXT-DD | SCLK(1) | Dual | DDR | 1Bh | 4 | Figure 81 | |
SRC-INT-DD | INTCLK(3) | Dual | DDR | 5Bh | 4 | Figure 82 | |
SRC-IB2-DD | INTCLK / 2(3) | Dual | DDR | 9Bh | 4 | ||
SRC-IB4-DD | INTCLK / 4(3) | Dual | DDR | DBh | 4 | ||
SRC-EXT-QD | SCLK(1) | Quad | DDR | 1Fh | 2 | Figure 85 | |
SRC-INT-QD | INTCLK(3) | Quad | DDR | 5Fh | 2 | Figure 86 | |
SRC-IB2-QD | INTCLK / 2(3) | Quad | DDR | 9Fh | 2 | ||
SRC-IB4-QD | INTCLK / 4(3) | Quad | DDR | DFh | 2 |
Figure 75 to Figure 86 show the details of various source synchronous protocols. Table 9 shows the number of output clocks required in an optimal read frame for the different output protocol selections.