USB251XB中文资料微芯科技数据手册PDF规格书

General Description

The Microchip USB251xB/xBi hub is a family of lowpower,

configurable, MTT (multi transaction translator)

hub controller IC products for embedded USB solutions.

The x in the part number indicates the number of

downstream ports available, while the B indicates battery

charging support. The Microchip hub supports lowspeed,

full-speed, and hi-speed (if operating as a hispeed

hub) downstream devices on all of the enabled

downstream ports.

Features

• USB251xB/xBi products are fully footprint compatible

with USB251x/xi/xA/xAi products as direct

drop-in replacements

— Cost savings include using the same PCB

components and application of USB-IF Compliance

by Similarity

• Full power management with individual or ganged

power control of each downstream port

• Fully integrated USB termination and pull-up/pulldown

resistors

• Supports a single external 3.3 V supply source;

internal regulators provide 1.2 V internal core voltage

• Onboard 24 MHz crystal driver or external

24 MHz clock input

• Customizable vendor ID, product ID, and device

ID

• 4 kilovolts of HBM JESD22-A114F ESD protection

(powered and unpowered)

• Supports self- or bus-powered operation

• Supports the USB Battery Charging specification

Rev. 1.1 for Charging Downstream Ports (CDP)

• The USB251xB/xBi offers the following packages:

- 36-pin SQFN (6x6 mm) (Preferred)

- 36-pin QFN (6x6 mm) (Legacy)

• USB251xBi products support the industrial temperature

range of -40ºC to +85ºC

• USB251xB products support the extended commercial

temperature range of 0ºC to +85ºC

Applications

• LCD monitors and TVs

• Multi-function USB peripherals

• PC motherboards

• Set-top boxes, DVD players, DVR/PVR

• Printers and scanners

• PC media drive bay

• Portable hub boxes

• Mobile PC docking

• Embedded systems