The **LM339L-P14-R** is a specific variant of the widely used LM339 family. It is a **Low Power Quad Voltage Comparator** designed to operate from a single power supply over a wide range of voltages. Below is a detailed breakdown of its electronic specifications and characteristics. --- ### 1. General Specifications The "L" in the part number often signifies "Low Power," and the "P14" refers to the package type. | Feature | Specification | | :--- | :--- | | **Number of Comparators** | 4 (Quad) | | **Supply Voltage (Single)** | +2V to +36V | | **Supply Voltage (Split/Dual)** | ±1V to ±18V | | **Supply Current** | 0.8mA (Typical, regardless of supply voltage) | | **Input Offset Voltage** | ±2mV (Typical) | | **Output Type** | Open Collector | | **Package Type** | TSSOP-14 or DIP-14 (Depending on manufacturer suffix) | --- ### 2. Pin Configuration (14-Pin Layout) The device contains four independent comparators sharing a single Vcc and Ground. | Pin Number | Function | Description | | :--- | :--- | :--- | | 1 | **OUTPUT 2** | Open collector output of 2nd comparator | | 2 | **OUTPUT 1** | Open collector output of 1st comparator | | 3 | **Vcc** | Positive Supply | | 4 | **INPUT 1-** | Inverting input of 1st comparator | | 5 | **INPUT 1+** | Non-inverting input of 1st comparator | | 6 | **INPUT 2-** | Inverting input of 2nd comparator | | 7 | **INPUT 2+** | Non-inverting input of 2nd comparator | | 8 | **INPUT 3-** | Inverting input of 3rd comparator | | 9 | **INPUT 3+** | Non-inverting input of 3rd comparator | | 10 | **INPUT 4-** | Inverting input of 4th comparator | | 11 | **INPUT 4+** | Non-inverting input of 4th comparator | | 12 | **GND** | Ground (or negative supply) | | 13 | **OUTPUT 4** | Open collector output of 4th comparator | | 14 | **OUTPUT 3** | Open collector output of 3rd comparator | --- ### 3. Key Electronic Characteristics #### A. Open Collector Output The output stage is an NPN transistor with an uncommitted collector. * **Pull-up Resistor:** You **must** use an external pull-up resistor to interface with logic families (TTL, CMOS). * **Voltage Level Shifting:** The pull-up resistor can be connected to a different voltage than Vcc (e.g., Vcc is 12V, but pull-up is 5V for MCU compatibility). #### B. Common-Mode Input Range The input common-mode voltage range includes ground (0V), even when operated from a single supply voltage. This makes it ideal for sensing signals near the negative rail. #### C. Low Power Consumption Designed for battery-operated devices, the drain current is significantly lower than standard operational amplifiers used as comparators. --- ### 4. Typical Applications * **Limit Comparators:** Checking if a signal is within a specific voltage window. * **Zero Crossing Detectors:** Detecting when an AC signal crosses 0V. * **Voltage Level Detectors:** Used in battery monitoring to trigger "Low Battery" LEDs. * **Oscillators:** Can be used to create square wave generators. --- ### 5. Part Number Suffix Decoding While coding varies by manufacturer (like UTC or TI), the "P14-R" usually breaks down as follows: * **P14**: 14-pin package. * **R**: Tape and Reel packaging (for automated PCB assembly).