AT43301-AU

Overview

The AT43301-AU is a USB hub controller supporting one upstream and four downstream ports, compliant with USB Specification Rev 1.1. It facilitates full-speed (12 Mb/s) and low-speed (1.5 Mb/s) data transfers using a 6 MHz oscillator and internal PLL. The device operates on a 4.4 V to 5.25 V supply, drawing 24 mA typically. It supports both bus-powered and self-powered configurations, featuring an on-chip 3.3 V regulator requiring a 0.27 µF capacitor at CEXT1. The component is housed in a 24-lead SOIC package.

Feature Summary

• Full compliance with USB Specification Revision 1.1 for standard connectivity
• Integrated Serial Interface Engine handling protocol management and signal encoding
• Supports both bus-powered and self-powered hub operational modes
• Includes port overcurrent monitoring and global power switching control

Applications

• Low-cost standalone USB hubs for portable computers
• Expansion of non-USB peripherals such as keyboards via USB connectivity
• Desktop peripheral connectivity solutions requiring multiple downstream ports

Procurement Notes

Verify the specific ordering suffix 'AU' against official Microchip documentation to confirm package type and temperature range specifications. Ensure compatibility with existing PCB layouts designed for the 24-lead SOIC form factor. Confirm that the design accommodates the required external components, including the 6 MHz crystal and 0.27 µF regulator capacitor, as detailed in the electrical specifications.

Selection Notes

Select this component for applications requiring strict adherence to USB 1.1 standards with minimal bill of materials. Consider the 6 MHz oscillator requirement for EMI reduction compared to higher frequency alternatives. Evaluate power budget constraints carefully, as bus-powered mode limits available current to downstream devices. Verify that the host system supports enumeration of standard USB hubs through Endpoint 0 and Endpoint 1.

Part Context

The AT43301 series includes variants such as the AT43301-SC in a 24-lead SOIC package and the AT43301-AC in a 32-lead LQFP package. The AT43301-AC variant specifically supports a 48 MHz clock input option, whereas the standard version utilizes a 6 MHz crystal. This model represents the low-cost solution within the Microchip USB hub controller portfolio.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation.