The **TS391CG-AF5-R** is a low-power, single voltage comparator designed for efficiency and versatility in space-constrained applications. It is commonly produced by manufacturers like **UTC (Unisonic Technologies)**. --- ### ## 1. Key Technical Specifications | Parameter | Specification | | :--- | :--- | | **Type** | Low Power Single Voltage Comparator | | **Supply Voltage Range** | 2V to 36V (Single) / ±1V to ±18V (Split) | | **Current Consumption** | ~0.8mA (Low Power) | | **Output Type** | Open Collector | | **Package Type** | SOT-25 / SOT-23-5 | | **Operating Temperature** | -40°C to +85°C | --- ### ## 2. Pin Configuration (SOT-25/AF5) The "AF5" suffix typically indicates the SOT-25 package. Below is the standard pinout for this part: 1. **OUT**: Output (Open Collector) 2. **VCC+**: Positive Power Supply 3. **VCC-**: Ground / Negative Power Supply 4. **IN-**: Inverting Input 5. **IN+**: Non-Inverting Input --- ### ## 3. Core Features and Functionality * **Wide Supply Range:** It can operate from a single lithium battery (3V) up to industrial 24V/36V rails. * **Open Collector Output:** This requires an external **pull-up resistor**. This feature allows the output to interface with different logic levels (e.g., the comparator runs on 12V, but the output pulls up to 3.3V for a microcontroller). * **Low Input Bias Current:** Minimizes errors when using high-impedance source signals. * **Common-Mode Input Range:** Includes ground, which is essential for single-supply applications. --- ### ## 4. Common Applications The TS391 is frequently used in the following circuits: * **Limit Comparators:** Checking if a voltage is above or below a threshold. * **Zero-Crossing Detectors:** Identifying when an AC signal crosses 0V. * **Pulse Generators:** Converting sine waves into square waves. * **Battery Monitors:** Triggering an LED or alarm when battery voltage drops. --- ### ## 5. Circuit Design Tip: The Pull-Up Resistor Because the output is an **Open Collector**, the device can only "sink" current to ground. It cannot "push" voltage out. To get a "High" signal, you must connect a resistor from the `OUT` pin to your desired logic voltage ($V_{pull-up}$). ```c // Simple logic representation If (IN+ > IN-) { Output = High-Impedance (Pulled up to VCC by resistor) } Else { Output = Ground (0V) } ```