The **U74AHC1G09L-AF5-R** is a high-speed, low-voltage CMOS logic device. Specifically, it is a **single 2-input AND gate with an open-drain output**. This part is commonly manufactured by UTC (Unisonic Technologies). --- ## 1. Technical Specifications The "AHC" series (Advanced High-Speed CMOS) provides a balance between high speed and low power consumption, maintaining compatibility with standard TTL levels. | Parameter | Specification | | :--- | :--- | | **Logic Type** | AND Gate (Single) | | **Output Type** | Open-Drain | | **Operating Voltage (Vcc)** | 2.0V to 5.5V | | **Input Type** | CMOS/TTL Compatible | | **Low Level Output Current** | 8 mA (at 4.5V) | | **Propagation Delay** | ~3.2 ns to 7.5 ns (depending on Vcc/CL) | | **Operating Temperature** | -40°C to +85°C | | **Package Type** | SOT-25 / SOT-23-5 (AF5) | --- ## 2. Pin Configuration (SOT-25) The device features a compact 5-pin layout, typical for "Little Logic" components. | Pin Number | Symbol | Function | | :--- | :--- | :--- | | 1 | B | Data Input | | 2 | A | Data Input | | 3 | GND | Ground (0V) | | 4 | Y | Output (Open-Drain) | | 5 | Vcc | Supply Voltage | --- ## 3. Key Functional Characteristics ### Open-Drain Output Unlike a standard push-pull output, the **Open-Drain** configuration means the device can only pull the output signal to **Low (GND)**. * To achieve a **High** state, an external **pull-up resistor** is required. * This allows for "wired-AND" logic applications and level shifting (e.g., interfacing a 3.3V gate with a 5V signal bus). ### Truth Table The logic follows the standard AND function: $Y = A \cdot B$. Note that the "H" state below is achieved via the external pull-up resistor. | Input A | Input B | Output Y | | :---: | :---: | :---: | | L | L | L (Active Drive) | | L | H | L (Active Drive) | | H | L | L (Active Drive) | | H | H | Z (High Impedance / Pull-up to High) | --- ## 4. Part Number Breakdown Understanding the nomenclature helps in identifying equivalent parts from other brands (like TI or Nexperia). * **U74**: UTC Logic Series. * **AHC**: Advanced High-speed CMOS technology. * **1G**: Single Gate device. * **09**: Function code for "2-Input AND gate with Open-Drain output". * **L**: Lead-free/Halogen-free. * **AF5**: Package code for SOT-25. * **R**: Tape & Reel packaging. ---