## Overview of the AM26LS32AI The **AM26LS32AI** is a quadruple differential line receiver designed for balanced or unbalanced digital data transmission. It is commonly used in industrial environments where noise immunity is critical, such as RS-422 and RS-423 communication interfaces. --- ### Key Technical Specifications The following table summarizes the primary electrical and physical characteristics of the AM26LS32AI: | Parameter | Specification | | :--- | :--- | | **Logic Family** | LS (Low-power Schottky) | | **Number of Receivers** | 4 (Quad) | | **Supply Voltage ($V_{CC}$)** | 4.75V to 5.25V (Standard 5V) | | **Input Threshold Voltage** | ±200 mV | | **Common-Mode Input Voltage** | ±7 V | | **Input Hysteresis** | 50 mV (Typical) | | **Propagation Delay** | 17 ns to 25 ns | | **Operating Temperature** | -40°C to 85°C (Industrial Grade) | | **Package Options** | SOIC, PDIP, SOP | --- ### Functional Components 1. **Differential Inputs (A and B):** These pins receive the differential signals. The chip detects the voltage difference between $V_A$ and $V_B$. If $V_A - V_B > 200mV$, the output is High. 2. **Enable Pins (G and $\bar{G}$):** These are "Active High" and "Active Low" enable pins that control all four receivers simultaneously. 3. **3-State Outputs (Y):** When the device is disabled via the enable pins, the outputs enter a high-impedance state, allowing multiple devices to share a common bus. --- ### Internal Logic Block Diagram (Simplified) ```text Input A1 ----(+)-----------+ | Receiver 1 |---- Output Y1 Input B1 ----(-)-----------+ Input A2 ----(+)-----------+ | Receiver 2 |---- Output Y2 Input B2 ----(-)-----------+ Enable G ---+----[ Control Logic ] Enable /G ---+ ``` --- ### Typical Application: RS-422 Receiver In a typical setup, the AM26LS32AI acts as the receiving end of a long-distance data line. Because it measures the **difference** in voltage rather than the absolute voltage relative to ground, it effectively cancels out electromagnetic interference (EMI) that affects both wires equally. **Connection Example:** - **Pin 1 (B1):** Connected to Negative Line. - **Pin 2 (A1):** Connected to Positive Line. - **Pin 3 (Y1):** Connected to Microcontroller RX pin (TTL level). - **Pin 16 ($V_{CC}$):** +5V DC. - **Pin 8 (GND):** Common Ground. ---