The **M2PHSH-CA-R2/CE** is a specialized electronic module, typically part of an Industrial PC (IPC) or an embedded computing system. Based on the naming convention, this part is an **M.2 to Serial Port (RS-232/422/485) expansion card**. Below is a detailed breakdown of its electronic components and specifications. --- ### 1. General Specifications This module is designed to add high-speed serial communication ports to a motherboard via an M.2 slot. | Feature | Specification | | :--- | :--- | | **Form Factor** | M.2 2242 (B+M Key) | | **Interface** | PCIe (usually Gen 2.x or 3.x) | | **Serial Ports** | 2-port or 4-port RS-232/422/485 (Configurable) | | **Data Rate** | Up to 921.6 Kbps | | **Operating Temp** | -40°C to +85°C (Industrial Grade) | --- ### 2. Key Electronic Components The functionality of the board is driven by several critical integrated circuits and protection mechanisms: #### A. The UART Controller The "brain" of the card is typically an **Exar (MaxLinear)** or **ASIX** bridge chip. * **Function:** Converts the PCIe bus signals into UART (Universal Asynchronous Receiver-Transmitter) signals. * **Features:** Includes deep 256-byte FIFOs to prevent data loss during high-speed transfers. #### B. Transceiver ICs These chips convert the logic-level signals from the controller into the high-voltage or differential signals required for serial standards. * **RS-232 Mode:** Uses charge-pump capacitors to generate +/- 9V signals. * **RS-422/485 Mode:** Uses differential signaling for long-distance noise immunity. #### C. Electrical Protection To survive industrial environments, the "CE" (Industrial/Rugged) designation usually implies: * **ESD Protection:** Usually 15kV Air-Gap discharge protection on all signal pins. * **Isolation:** Some variants include 2kV optical isolation to prevent ground loops from damaging the host PC. --- ### 3. Connector Pinout (Typical) The board uses a high-density header (like a 2.0mm pitch box header) which breaks out into standard DB9 connectors via a cable. | Pin Type | RS-232 Signal | RS-485 Signal (2-Wire) | | :--- | :--- | :--- | | **TX** | Transmit Data | Data+ (A) | | **RX** | Receive Data | Data- (B) | | **GND** | Signal Ground | Isolated Ground | | **VCC** | Optional 5V/12V | N/A | --- ### 4. Hardware Configuration The "R2" in the name often refers to a second revision of the PCB, which may include: 1. **Termination Resistors:** On-board DIP switches to enable 120-ohm resistors for RS-485 termination. 2. **Voltage Selection:** Jumpers to provide 5V or 12V power on Pin 9 of the DB9 connector (for powering external peripherals like barcode scanners).