SLLSFI6A july 2022 – july 2023 TDP1204
PRODUCTION DATA
The TDP1204 can be designed into many different applications. In all the applications there are certain requirements for the system to work properly. The EN pin must have a 0.1-µF capacitor to ground. The processor can drive the EN pin, but the EN pin needs to change states (low to high) after the voltage rails have stabilized. Using I2C is the best way to configure the device, but pin strapping is also provided as I2C and is not available in all cases. As sources may have many different naming conventions, it is necessary to confirm that the link between the source and the TDP1204 are correctly mapped. A Swap function is provided for the input pins in case signaling is reversed between the source and receptacle. Table 9-1 lists information on expected values to perform properly.
For this design example, the TDP1204 is assumed to be configured for pin-strap mode. If I2C mode is desired, the MODE pin should be set to "F" and software must configure TDP1204. For how to configure TDP1204, refer to Section 8.4.1.
Design Parameter | Value |
---|---|
VCC | 3.3-V |
VIO (1.2-V, 1.8-V, or 3.3-V LVCMOS levels) | 1.8-V |
Maximum HDMI 2.1 FRL Datarate (3, 6, 8, 10, or 12-Gbps) | 12-Gbps |
Pin-strap or I2C mode (if I2C, then MODE = "F"). | Pin-strap |
Pin Strap Mode.(MODE = "0", "R" or "1"). | Mode = "0" (Fixed EQ with DDC Buffer support) |
DDC Snoop Feature. (Y/N). Required when in pin strap. Optional in I2C mode. | Yes |
SWAP function (Y / N). In pin strap mode controlled by SDA/CFG1 pin. | No. SDA/CFG1 pin = L. |
DDC Level Shifter Support (Y / N) | Yes |
HPD_IN to HPD_OUT Level Shifter Support (Y / N) | Yes, HPD_OUT is used. If no, then HPD_OUT can be left floating. |
Pre-Channel Length (Table 9-2 provides the length restrictions) | Length = 8 inches (≅ 7.2-dB at 6-GHz insertion loss) |
Post-Channel Length (Table 9-2 provides the length restrictions) | Length = 2 inches (≅ 1.8-dB at 6-GHz insertion loss) |
Limited or linear redriver mode? | Limited redriver (LINEAR_EN pin = "0"). |
TX is DC or AC-coupled to HDMI receptacle? | DC-coupled. AC_EN pin = Low. |
GPU Launch Voltage (500 mV to 1200 mV) if using limited redriver mode. If using linear redriver mode, then refer to the GPU requirements listed in Table 8-4. | 500-mV |
GPU HDMI 2.1 pre-shoot and de-emphasis levels used if using redriver in limited mode | If MODE = "0" or "R", GPU's TX FFE pre-shoot and de-emphasis levels shall be set
to 0-dB for all four TXFFE levels If MODE = "1", then GPU TXFFE pre-shoot and de-emphasis levels shall meet the requirements listed in Table 8-4. |
CTLE HDMI Datarate Map (Map A, Map B, or Map C) | Map C |
RX EQ (16 possible values. Value chosen based on pre-channel length). | EQ1 pin: "R" ADDR/EQ0 pin: "R"(7.5-dB) |
TX Pre-emphasis. In pre-strap mode controlled by TXPRE pin. | Default 0-dB of pre-emphasis. Float TXPRE pin. |
TX Swing. In pre-strap mode controlled by TXSWG pin. | Default TX swing level. Float TXSWG pin. |
Symbol | Parameter | Condition | Min | Typ | Max | Units |
---|---|---|---|---|---|---|
RESD | External series resistor between ESD component and TDP1204 | 0 | 2.5 | Ω | ||
LAB(1)(3) | PCB trace length from GPU to TDP1204 | At 12-Gbps | 1 | 10 | inches | |
LINTRA-AB | Intra-pair skew from GPU to TDP1204 | 5 | mil | |||
LCD(1) | PCB trace length from TDP1204 to receptacle | At 12-Gbps | 0.75 | 2 | inches | |
LINTRA-CD | Intra-pair skew from TDP1204 to receptacle | 5 | mil | |||
LCAP-RX | PCB trace length from TDP1204 to optional external CAC-RX capacitor | 0.3 | inches | |||
LCAP-TX | PCB trace length from TDP1204 to optional external CAC-TX capacitor | 0.3 | inches | |||
LESD | PCB trace length from ESD component to receptacle | 0.5 | inches | |||
LR_ESD | PCB trace length from RESD to ESD component | 0.25 | inches | |||
LINTER-PAIR(3) | Inter-pair skew between all four channels (D0, D1, D2, and CLK) | 1 | inches | |||
ILPCB | PCB trace insertion loss | 0.1 | 0.17 | dB / inch / GHz | ||
ZPCB_AB | Differential impedance of LAB | 75 | 110 | Ω | ||
ZPCB_CD | Differential impedance of LCD | 90 | 110 | Ω | ||
VIAAB | Number of vias between GPU and TDP1204 | 2 | VIA | |||
VIACD | Number of vias between HDMI connector and TDP1204 | 1 | VIA | |||
XTALK | Differential crosstalk between adjacent differential pairs on PCB. | ≦ 3 GHz | −24 | dB |