JAJST20 March 2024 DLPC964
PRODUCTION DATA
The output differential voltage (Vod), driver preemphasis, and driver post-emphasis settings for the HSSI output drivers of the DLPC964 controller can be adjusted from the default settings to modify the performance of the DMD High Speed Serial Interface. Separate control of these settings for each data bus (A, B, C, D) and each data bus clock (A,B,C,D) are available, as well as the common-mode voltage (Vcm) settings for the HSSI receiver in the DMD through the I2C register interface in the DLPC964 controller.
Table 6-3 describes the different settings available for the HSSI drivers in the DLPC964 controller. When changing driver output differential voltage (Vod), driver preemphasis, and driver post-emphasis settings for the HSSI output drivers of the DLPC964 controller from the default settings, the common-mode voltage (Vcm) of the signals at the DMD HSSI receivers can change. Measurement and verification that the input differential voltage (Vid) and input common mode voltage (Vcm) are within the voltage specifications described in the Recommended Operation Conditions section of the DLP991U DMD data sheet is necessary to verify these voltage levels are within the correct specifications after being modified. See the AMD 7 Series FPGAs GTX/GTH Transceivers User Guide for more information.
TXDIFFCTRL(1) | TXPOSTCURSOR(2) | TXPRECURSOR(3) | |||||||
---|---|---|---|---|---|---|---|---|---|
[3:0] | VPPD | [12:8] | Emphasis (dB) | |Coefficient Units| | [20:16] | Emphasis (dB) | |Coefficient Units| | ||
4'b0000 | 0.269 | 5'b00000 | 0.00 | 0 | 5'b00000 | 0.00 | 0 | ||
4'b0001 | 0.336 | 5'b00001 | 0.22 | 1 | 5'b00001 | 0.22 | 1 | ||
4'b0010 | 0.407 | 5'b00010 | 0.45 | 2 | 5'b00010 | 0.45 | 2 | ||
4'b0011 | 0.474 | 5'b00011 | 0.68 | 3 | 5'b00011 | 0.68 | 3 | ||
4'b0100 | 0.543 | 5'b00100 | 0.92 | 4 | 5'b00100 | 0.92 | 4 | ||
4'b0101 | 0.609 | 5'b00101 | 1.16 | 5 | 5'b00101 | 1.16 | 5 | ||
4'b0110 | 0.677 | 5'b00110 | 1.41 | 6 | 5'b00110 | 1.41 | 6 | ||
4'b0111 | 0.741 | 5'b00111 | 1.67 | 7 | 5'b00111 | 1.67 | 7 | ||
4'b1000 | 0.807 | 5'b01000 | 1.94 | 8 | 5'b01000 | 1.94 | 8 | ||
4'b1001 | 0.866 | 5'b01001 | 2.21 | 9 | 5'b01001 | 2.21 | 9 | ||
4'b1010 | 0.924 | 5'b01010 | 2.50 | 10 | 5'b01010 | 2.50 | 10 | ||
4'b1011 | 0.973 | 5'b01011 | 2.79 | 11 | 5'b01011 | 2.79 | 11 | ||
4'b1100 | 1.018 | 5'b01100 | 3.10 | 12 | 5'b01100 | 3.10 | 12 | ||
4'b1101 | 1.056 | 5'b01101 | 3.41 | 13 | 5'b01101 | 3.41 | 13 | ||
4'b1110 | 1.092 | 5'b01110 | 3.74 | 14 | 5'b01110 | 3.74 | 14 | ||
4'b1111 | 1.119 | 5'b01111 | 4.08 | 15 | 5'b01111 | 4.08 | 15 | ||
5'b10000 | 4.44 | 16 | 5'b10000 | 4.44 | 16 | ||||
5'b10001 | 4.81 | 17 | 5'b10001 | 4.81 | 17 | ||||
5'b10010 | 5.19 | 18 | 5'b10010 | 5.19 | 18 | ||||
5'b10011 | 5.60 | 19 | 5'b10011 | 5.60 | 19 | ||||
5'b10100 | 6.02 | 20 | 5'b10100 | 6.02 | 20 | ||||
5'b10101 | 6.47 | 21 | 5'b10101 | 6.02 | 21 | ||||
5'b10110 | 6.94 | 22 | 5'b10110 | 6.02 | 22 | ||||
5'b10111 | 7.43 | 23 | 5'b10111 | 6.02 | 23 | ||||
5'b11000 | 7.96 | 24 | 5'b11000 | 6.02 | 24 | ||||
5'b11001 | 8.52 | 25 | 5'b11001 | 6.02 | 25 | ||||
5'b11010 | 9.12 | 26 | 5'b11010 | 6.02 | 26 | ||||
5'b11011 | 9.76 | 27 | 5'b11011 | 6.02 | 27 | ||||
5'b11100 | 10.46 | 28 | 5'b11100 | 6.02 | 28 | ||||
5'b11101 | 11.21 | 29 | 5'b11101 | 6.02 | 29 | ||||
5'b11110 | 12.04 | 30 | 5'b11110 | 6.02 | 30 | ||||
5'b11111 | 12.96 | 31 | 5'b11111 | 6.02 | 31 |
Table 6-4 describes the different common-mode voltage (Vcm) settings available for the HSSI receivers in the DLP991U DMD. This register must be set to best match the input common-mode voltage (Vcm) at the DLP991U HSSI receivers. If the common-mode voltage at the DMD HSSI receiver does not match the HSSI receiver common-mode voltage register settings in the DLPC964 controller, the performance of the DMD HSSI can be negatively affected.
VCM REGISTER SETTING | VCM INPUT RANGE |
---|---|
3'b000 | 0.759V – 0.800V |
3'b001 | 0.673V – 0.758V |
3'b010 | 0.587V – 0.672V |
3'b011 | 0.501V – 0.586V |
3'b100 | 0.415V – 0.500V |
3'b101 | 0.329V – 0.414V |
3'b110 | 0.243V – 0.328V |
3'b111 | 0.200V – 0.242V |
To modify the HSSI settings at power-up:
To modify the HSSI settings during normal operation (after power-up):