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DS00002774G-page 7

USB4712

2.0

INTRODUCTION

2.1

General Description

The Microchip family of USB4712 USB 2.0 Hi-Speed hub retimers are single-chip devices targeted for automotive appli-

cations. Primary functions of the devices include: single downstream USB port supporting USB 2.0 Low Speed/Full

Speed/Hi-Speed, single USB 2.0 Hi-Speed upstream connection to a USB host / OTG port, battery charging support for

BC1.2, Apple and China charging profiles, USB I/O bridging, and an on-chip microcontroller.

The USB4712 family employs unique Auto-FlexConnect USB functionality, whereby the downstream port can be recon-

figured to become an upstream port, allowing the host or master capability to be switched between ports. This port/host

becomes the master of the new USB bus, while the other port can connect as USB device.

The USB4712 devices are available in an Automotive Grade 3 (-40°C to +85°C) temperature range. An internal block

diagram of the USB4712 is shown in Figure 2-1.

The USB4712 family of devices offer different feature sets depending upon the system needs. Specifically, FlexConnect

can be executed automatically via a package pin or USB command. In some cases, the chip is capable of being cas-

caded. Additionally, the Hub Feature Controller, which can be used for bridging, can be enabled/on or disabled/off.

Table 2-1 provides a summary of the feature differences between family members.

Note:

Auto-FlexConnect requires Battery Charging v1.2 to always be enabled to function. BC1.2 on USB4712PF

may be optionally enabled or disabled without any negative effect.

FIGURE 2-1:

INTERNAL BLOCK DIAGRAM

TABLE 2-1:

FAMILY FEATURE MATRIX

Part Number

Target

Applications

Supports

Head Unit

Suspend

State

Cascadeable Trigger FlexConnect

Hub Feature

Controller

USB4712

Passenger Port

Yes

No

Automatic when new

host detected

On when not flexed

(turns off when flexed)

USB4712PF

Passenger Port or



Cable Extender

Yes

Yes

Executed via package

pin or USB command

Always off

USB4712LS

Passenger Port or



Cable Extender

No

Yes

Automatic when new

host detected

On when not flexed

(turns off when flexed)

USB4712

25 MHz

3.3V

FlexHub Controller

Flex

Port 1

USB

Flex USB 2.0

Hub Feature

Controller

I/O Multiplexer

I

OTP

I/O

USB Host / OTG Port 0