SNLS231P September 2006 – August 2024 DS90UR124-Q1 , DS90UR241-Q1
PRODUCTION DATA
The DS90UR124 Deserializer supports two signal quality enhancers. The SLEW pin is used to increase the drive strength of the LVCMOS outputs when driving heavy loads. SLEW allows output drive strength for high or low current drive. Default setting is LOW for low drive at 2mA and HIGH for high drive at 4mA.
There are two types of Progressive Turnon modes (Fixed and PTO Frequency Spread) to help reduce EMI: simultaneous switching noise and system ground bounce. The PTOSEL pin introduces bank skew in the data/clock outputs to limit the number of outputs switching simultaneously. For Fixed-PTO mode, the Deserializer ROUT[23:0] outputs are grouped into three groups of eight, with each group switching about 2 or 1 UI apart in phase from RCLK for Group 1 and Groups 2, 3, respectively (see Figure 5-15). In the PTO Frequency Spread mode, ROUT[23:0] are also grouped into three groups of eight, with each group is separated out of phase with the adjacent groups (see Figure 5-16) per every 4 cycles. Note that in the PTO Frequency Spread operating mode RCLK is also spreading and separated by 1 UI.