The **M5R28XHJ-R** is a high-performance, differential output crystal oscillator (XO) designed for precision timing applications. It is part of the M5R series, typically manufactured by suppliers like MtronPTI. ### 1. Key Technical Specifications The component is characterized by its low jitter and high-speed differential signaling. Below are the primary technical parameters: | Parameter | Specification | | :--- | :--- | | **Output Type** | HCSL (Host Clock Signal Level) | | **Supply Voltage (Vcc)** | 3.3V (Typical) | | **Frequency Range** | Typically fixed (e.g., 100MHz, 125MHz, 156.25MHz) | | **Operating Temperature** | -40°C to +85°C (Industrial Grade) | | **Package Size** | 5.0 x 7.0 mm (6-pad SMD) | | **Stability** | ±50ppm or ±25ppm (depending on sub-variant) | --- ### 2. Functional Characteristics #### Differential Output (HCSL) The "H" in the suffix usually denotes **HCSL** logic. This is a current-steering output technology that provides: * Fast rise and fall times. * Low power consumption compared to LVPECL. * Excellent noise immunity, making it ideal for high-speed serial links. #### Jitter Performance This part is engineered for "Ultra-Low Jitter." In high-speed data transmission, jitter represents the deviation in the timing of the clock edges. Low jitter ensures that data bits are sampled correctly at the receiving end without errors. --- ### 3. Pin Configuration (Typical 6-Pad SMD) | Pin # | Function | Description | | :--- | :--- | :--- | | **1** | E/D or NC | Enable/Disable (Tri-state) or No Connect | | **2** | NC | No Connect | | **3** | GND | Ground | | **4** | Output | Positive Output (Q) | | **5** | Output | Complementary Output (nQ) | | **6** | Vcc | Supply Voltage | --- ### 4. Common Applications The M5R28XHJ-R is primarily used in environments where timing precision and signal integrity are critical: * **PCI Express (PCIe) Gen 3/4/5:** HCSL is the standard clocking requirement for PCIe. * **Networking:** Gigabit Ethernet, Switches, and Routers. * **Fiber Channel:** Storage area networks. * **FPGA Clocking:** Providing high-speed reference clocks to Xilinx or Intel FPGAs. --- ### 5. Part Number Breakdown (General MtronPTI Logic) * **M5R:** Series identifier (5x7mm SMD, 3.3V). * **28:** Temperature Stability/Range code. * **X:** Custom or specific feature set. * **H:** HCSL Output logic. * **J:** Symmetry/Duty Cycle requirements. * **-R:** RoHS Compliant / Tape and Reel packaging.