## Overview of the UM-1-R Electronic Component The **UM-1-R** refers to a specific type of **Quartz Crystal Resonator**. It is widely used in electronic circuits to provide a stable clock frequency or reference signal. The "UM-1" designation refers to the physical package size (a tall, slim metal can), while the "R" typically signifies that the part is **RoHS compliant** (lead-free). --- ### 1. Key Technical Specifications A typical UM-1-R crystal unit features the following technical characteristics: | Parameter | Typical Value / Range | | :--- | :--- | | **Frequency Range** | 1.0 MHz to 200 MHz | | **Package Type** | Through-hole (Metal Can) | | **Frequency Tolerance** | ±10 ppm to ±50 ppm | | **Frequency Stability** | ±10 ppm to ±50 ppm | | **Operating Temperature** | -20°C to +70°C (Standard) | | **Load Capacitance** | 12pF, 20pF, or Series | | **Drive Level** | 10µW to 100µW | --- ### 2. Physical Characteristics The UM-1 is a "slimmer" alternative to the classic HC-49/U package. It is designed for applications where vertical space is available but PCB real estate is limited. * **Height:** Approximately 8.0 mm to 8.1 mm. * **Mounting:** Through-hole (leads are inserted into the PCB). * **Sealing:** Resistance welded for hermetic protection against moisture and contaminants. --- ### 3. Functional Mechanism The UM-1-R operates on the principle of **Piezoelectricity**. 1. **Input:** An electric field is applied to the quartz wafer inside the metal can via the leads. 2. **Vibration:** The quartz wafer vibrates at a very precise mechanical frequency. 3. **Output:** This mechanical vibration is converted back into an electrical signal, which the circuit uses as a stable timing heartbeat. --- ### 4. Common Applications Due to its high Q-factor (quality factor) and stability, the UM-1-R is found in: * **Radio Communication:** Used in filters and oscillators for transceivers. * **Microprocessors:** Providing the base clock for CPUs and MCUs. * **Consumer Electronics:** Older video equipment, clocks, and measuring instruments. * **Telecommunications:** Network synchronization modules. --- ### 5. Circuit Example (Oscillator) In a standard Pierce Oscillator circuit, the UM-1-R is connected between the input and output of an inverter. ```cpp // Schematic Representation // +-----------[ R1 ]-----------+ // | | // ----o----[ C1 ]----(GND) | // | | | // [XTAL UM-1-R] [ Inverter/MCU ] // | | | // ----o----[ C2 ]----(GND) | // | | // +----------------------------+ ```