DP interface level standard

The core conclusion of the DP interface level standard is as follows: 3.3V power supply, 100Ω impedance matching, differential signal driving. Voltage deviation exceeding ±10% may cause synchronization failure or hardware damage.

1. Signal transmission principle:
The DP interface transmits data through four pairs of low differential signals. Each pair of signals adopts the design of low level indicating logic 0 and high level indicating logic 1. This differential transmission mechanism can reduce electromagnetic interference while increasing the signal transmission rate.

2. Electrical specification parameters:
According to the VESA standard, the working voltage of the signal lines is strictly limited to a range of 3.3V ± 10% (i.e., 2.97 - 3.63V), and the impedance of the signal channel needs to be stable at 100Ω ± 5%. This design ensures that the eye diagram opening remains when transmitting at speeds above 5.4Gbps.

3. DP_PWR pin specification:
The power supply pin requires a mandatory 3.3V direct current input. This voltage value serves as the power supply reference for all chips in the entire interface. If a 5V power supply is connected, it will trigger the protection circuit to shut down. If the voltage is lower than 3V, the effective handshake protocol cannot be established, and there may be a black screen or screen flicker.

4. Maintenance practice verification:
Actual cases show that if the DP_PWR voltage exceeds 3.6V, it may break the TVS diode of the main control chip, and if it is lower than 2.8V, the hot plugging detection function will fail. It is recommended to use a digital multimeter with an accuracy of no less than ±2% for power supply detection.