TX(transmitter) and Rx(Receiver) are there in LPDDR, so why do we place TX near to ESD device? why not RX?

In an I/O (Input/Output) device floorplan, both transmitters (TX) and receivers (RX) are essential components for communication with external devices. The placement of these components, especially the TX near ESD (Electrostatic Discharge) protection devices, is a strategic design choice.

TX and RX play different roles in I/O communication:

Transmitter (TX): The TX component is responsible for sending data or signals from the device to the external world. It generates and drives the electrical signals out. In LPDDR (Low Power Double Data Rate) interfaces, this is often associated with sending data to memory or other peripherals.

Receiver (RX): The RX component, on the other hand, receives data or signals from external sources, such as memory modules or other devices, and processes them for the device to use.

ESD protection devices are crucial to safeguard the I/O pins and the overall device from electrostatic discharges, which can damage or disrupt the operation of electronic components.

So, when it comes to the placement of TX and RX near ESD protection devices, it's typically a matter of signal integrity and design considerations. Placing the TX near ESD protection is a common practice because:

Outgoing signals are often more sensitive to noise and interference than incoming signals. Placing the TX near ESD protection helps protect the device and the signal integrity of the transmitted data. This positioning reduces the risk of ESD-induced damage and distortion for the signals leaving the device.

TX signals are actively driven by the device, which means they have a higher current and voltage compared to RX signals. Therefore, it's important to ensure that TX signals are protected from any potential ESD events.

Proper placement of TX and ESD protection devices is part of a comprehensive ESD protection strategy that aims to minimize the chances of damage to the device. RX components may also have their own ESD protection, but TX components are often given more priority because of their active role in signal transmission.

In summary, TX components are placed near ESD protection devices in an I/O device floorplan to ensure the protection of outgoing signals and to maintain signal integrity, as outgoing signals are generally more sensitive to ESD-related issues. While RX components may also have ESD protection, TX components are strategically positioned to mitigate the risks associated with transmitting data.

One other reason is that, TX has hight voltage(VDDIO) device(IO), like Driver, while RX has core voltage(VDDA) devices, so in order to make Power plan also it is easy to place ESD device near to TX because ESD device has also High voltage(VDDIO).

In short, in power planning also this floorplan is better.