SLLSFI6A july 2022 – july 2023 TDP1204
PRODUCTION DATA
The TDP1204 provides pre-emphasis and de-emphasis on the data lanes allowing the output signal pre-conditioning to offset interconnect losses between the TDP1204 outputs and a TMDS receiver. Pre-emphasis and de-emphasis is not implemented on the clock lane unless the TDP1204 is in HDMI 2.1 FRL mode and at which time the clock lane becomes a data lane. There are two methods to implement pre-emphasis, pin strapping or through I2C programming. TX pre-emphasis and de-emphasis control is only supported in limited mode.
When using pin strap mode, the TXPRE pin controls four different global pre-emphasis and de-emphasis values for all data lanes when TDP1204 is operating in HDMI 1.4 or HDMI 2.0. Table 8-15 lists these pre-emphasis and de-emphasis values. In HDMI 2.1 FRL mode, the de-emphasis value used is based on the DDC TXFFE snooped value. Table 8-16 lists how the TDP1204 uses the de-emphasis level for each TX FFE level.
LINEAR_EN pin = "0" | LINEAR_EN pin = "F" or "1" | LINEAR_EN pin = "R" | |||
---|---|---|---|---|---|
TXPRE pin | HDMI 1.4 or HDMI 2.0 | HDMI 2.1
FRL TXFF0 Level |
AEQ ADJUSTMENT | AEQ ADJUSTMENT | AEQ ADJUSTMENT |
0 | 3.5 dB pre-emphasis |
Refer to Table 8-16. |
0 |
+1 |
0 |
R | -2.5 dB de-emphasis |
Refer to Table 8-16. |
0 |
+4 |
0 |
F | 0 dB |
Refer to Table 8-16. |
0 |
0 |
0 |
1 | 6.0 dB pre-emphasis |
Refer to Table 8-16 |
0 |
+2 |
0 |
FRL TX FFE Snooped Level | De-Emphasis (dB) |
---|---|
TXFFE0 | -2.5 |
TXFFE1 | -3.5 |
TXFFE2 | -3.7 |
TXFFE3 | -4.6 |