ZHCSFY1F December 2016 – April 2024 TDP158
PRODUCTION DATA
The TDP158 provides pre-emphasis on the data lanes allowing the output signal pre-conditioning to offset interconnect losses between the TDP158 outputs and a TMDS receiver. Pre-emphasis is not implemented on the clock lane unless the TDP158 is in DP mode; at which time, it becomes a data lane. The default value for pre-emphasis is 0dB. There are two methods to implement pre-emphasis, pin strapping or through I2C programming. When using pin strapping, the SDA_CTL/PRE pin controls global pre-emphasis values of 0dB or 3.5dB. Through I2C, reg0Ch[1:0] pre-emphasis values are 0dB, 3.5dB, and 6dB. The 6dB value has different meanings when the device is in normal operational mode (reg09h[5] = 0) or when the TDP158 has been put into DP-mode (reg09h[5] = 1). As Figure 7-6 shows, the 6dB pre-emphasis setting will result in an output of 3dB of pre-emphasis with 3dB of de-emphasis when device is in normal HDMI operation. As Figure 7-7 shows, the output will be about 5dB pre-emphasis with a 1dB de-emphasis when selecting 6dB pre-emphasis setting for DP-mode. VOD(PP) value will not go above 1V.
Global Control | Independent Lane Control | |||||
---|---|---|---|---|---|---|
Mode | Reg09h[6] Lane CTL | Reg09[5] Mode CTL | P0_Reg0C[7:0] | Reg09h[6] Lane CTL | Reg09[5] Mode CTL | P0_Reg0C[7:0] |
HDMI | 0 | 0 | 8’h00 | 1 | 0 | 8’h00 |
DP SWG0, PRE0 | 0 | 1 | 8’h80 | 1 | 1 | 8’h80 |
DP SWG0, PRE1 | 0 | 1 | 8’hC1 | 1 | 1 | 8’hC1 |
DP SWG0, PRE2 | 0 | 1 | 8’h42 | 1 | 1 | 8’h42 |
DP SWG1, PRE0 | 0 | 1 | 8’hC0 | 1 | 1 | 8’hA0 |
DP SWG1, PRE1 | 0 | 1 | 8’hF1 | 1 | 1 | 8’h21 |
DP SWG1, PRE2 | 0 | 1 | 8’h52 | 1 | 1 | 8’h62 |
DP SWG2, PRE0 | 0 | 1 | 8’h20 | 1 | 1 | 8’h00 |
DP SWG2, PRE1 | 0 | 1 | 8’h51 | 1 | 1 | 8’h61 |