## Overview of the TUSB321AI The **TUSB321AI** is a USB Type-C Configuration Channel (CC) logic and Port Control integrated circuit (IC). It is designed to enable USB Type-C systems to determine port attachment and detachment, cable orientation, and role detection (Source, Sink, or Dual-Role Power). --- ### Core Specifications The following table summarizes the key electrical and physical characteristics of the TUSB321AI: | Parameter | Specification | | :--- | :--- | | **Supply Voltage (VDD)** | 4.5 V to 5.5 V | | **Current Consumption** | Active: 332 µA (Typical) / Shutdown: 1.3 µA | | **Interface Roles** | Source (DFP), Sink (UFP), or DRP (Dual Role) | | **Detection Method** | Configuration Channel (CC) pins (CC1, CC2) | | **Temperature Range** | -40°C to 85°C (Industrial Grade) | | **Package Type** | 12-pin X2QFN (1.6 mm x 1.6 mm) | --- ### Key Electronic Components & Pin Functions The TUSB321AI operates by monitoring the voltage levels on the CC lines. Here are the primary functional pins: #### 1. Configuration Channel Pins (CC1 & CC2) These pins are used to detect cable attachment and orientation. The IC automatically applies the necessary pull-up ($R_p$) or pull-down ($R_d$) resistors depending on the mode selected. #### 2. PORT Pin This is a tri-state input pin used to configure the device role: * **GND:** Sink (Upstream Facing Port - UFP). * **VDD:** Source (Downstream Facing Port - DFP). * **High-Z (Unconnected):** Dual-Role Power (DRP). #### 3. ADDR Pin Defines the I2C address of the device. If I2C is not used (GPIO mode), this pin is typically tied to GND. #### 4. CURRENT_MODE Pins These pins allow the system to advertise different USB power capabilities: * **Default USB Power:** 500mA/900mA. * **1.5 A:** Medium current. * **3.0 A:** High current. --- ### Operating Modes The TUSB321AI can operate in two primary modes: 1. **GPIO Mode:** This is a "stand-alone" mode where the IC uses physical pins (like `OUT1`, `OUT2`, and `ID`) to signal status to a microcontroller or power management IC without needing software overhead. 2. **I2C Mode:** This allows a host processor to communicate with the TUSB321AI to read status registers, change roles dynamically, and monitor more detailed connection events. --- ### Simplified Application Circuit Below is a conceptual representation of how the TUSB321AI sits between the USB-C connector and the system power delivery logic. ```mermaid graph LR A[USB-C Connector] -- CC1/CC2 --> B[TUSB321AI] B -- Status/ID --> C[Application Processor] B -- Enable --> D[Power Switch / VBUS] ``` --- ### Common Applications * Smartphones and Tablets * Industrial PC peripherals * USB-C Wall Chargers * Power Banks (Portable Chargers)