The **U74LVC573G-P20-R** is a high-performance, low-voltage CMOS octal transparent latch with 3-state outputs. It is commonly used in bus-oriented systems as a buffer or storage element. ### 1. General Specifications Below are the primary technical parameters for the device: | Parameter | Specification | |:---|:---| | **Function** | Octal Transparent D-Type Latch | | **Logic Family** | LVC (Low Voltage CMOS) | | **Operating Voltage ($V_{CC}$)** | 1.65V to 3.6V | | **Output Type** | 3-State (Tri-state) | | **Package Type** | TSSOP-20 (Standard for P20-R suffix) | | **Operating Temperature** | -40°C to +85°C (Standard Industrial) | | **Drive Capability** | ±24 mA at 3.0V | --- ### 2. Pin Configuration and Functions The device features 20 pins, designed for easy PCB routing where inputs are on one side and outputs on the opposite side. * **Inputs ($D_0$ - $D_7$):** Data inputs. * **Outputs ($Q_0$ - $Q_7$):** Data outputs. * **Latch Enable (LE):** When HIGH, the latch is transparent (Output follows Input). When LOW, the data is latched. * **Output Enable ($\overline{OE}$):** When LOW, outputs are active. When HIGH, outputs are in a high-impedance state (Hi-Z). --- ### 3. Logic Truth Table The operation of the U74LVC573G is defined by the following logic states: | Operating Mode | $\overline{OE}$ | LE | D | Output (Q) | |:---|:---:|:---:|:---:|:---:| | **Transparent** | L | H | L | L | | **Transparent** | L | H | H | H | | **Latched** | L | L | X | $Q_0$ (No Change) | | **High Impedance** | H | X | X | Z | --- ### 4. Key Features * **5V Tolerance:** The inputs and outputs (in 3-state mode) can handle up to 5.5V, allowing the chip to interface between 3.3V and 5V systems. * **Low Power Consumption:** Ideal for battery-powered applications due to CMOS technology. * **$I_{off}$ Protection:** Supports partial-power-down mode operation. It prevents damaging backflow current through the device when it is powered down. * **Flow-Through Architecture:** Inputs are directly across from outputs, simplifying high-speed board layout. --- ### 5. Application Examples The U74LVC573G is typically used in: 1. **Address De-multiplexing:** Separating address and data lines in microcontroller circuits. 2. **Bus Buffering:** Driving heavy capacitive loads in backplanes. 3. **Digital Signal Isolation:** Using the 3-state outputs to isolate segments of a data bus.