AT43301-AC

Overview

The AT43301-AC 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 5V supply (4.4V to 5.25V), consuming 24mA, and includes an on-chip 3.3V regulator requiring a 0.27µF capacitor at CEXT1. It supports bus-powered or self-powered modes, featuring port overcurrent monitoring via the OVC pin and power switching control via the PWR pin. The 32-lead LQFP package provides a dedicated 48 MHz clock input.

Feature Summary

• Full compliance with USB Specification Revision 1.1 for reliable protocol handling
• Integrated 3.3V voltage regulator simplifies power distribution within the hub circuitry
• Supports both bus-powered and self-powered operational configurations
• Includes global port overcurrent detection and external power switching control

Applications

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

Procurement Notes

Verify component authenticity through authorized Microchip Technology distributors. Confirm the specific AC suffix indicates the 32-lead LQFP package with 48 MHz clock capability. Ensure the source documentation matches the official datasheet revision. Check for RoHS compliance status if required by local regulations. Validate that the supplier provides genuine parts without modification.

Selection Notes

Select the AT43301-AC when a 32-lead LQFP package is preferred over the 24-lead SOIC variant. This version requires a 48 MHz clock input if the 48N pin is grounded, differing from the standard 6 MHz crystal requirement. Ensure the design accommodates the specific pinout differences between the AC and SC packages. Verify that the application supports USB 1.1 speeds, as this controller does not support high-speed transactions.

Part Context

The AT43301 series serves as a low-cost solution for USB hub implementations. The AT43301-SC utilizes a 24-lead SOIC package, while the AT43301-AC uses a 32-lead LQFP package. Both variants share identical functional capabilities regarding port management and protocol handling. The primary distinction lies in the physical packaging and the availability of a dedicated 48 MHz clock input on the AC version.

Replacement Considerations

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