USB334X datasheet(32/92 Pages) MICROCHIP

32 / 92 page

USB334x

DS00002646A-page 32

 2009-2018 Microchip Technology Inc.

5.7

USB On-The-Go (OTG)

The USB334x provides support for the USB OTG protocol. OTG allows the USB334x to be dynamically configured as

a host or peripheral depending on the type of cable inserted into the Micro-AB receptacle. When the Micro-A plug of a

cable is inserted into the Micro-AB receptacle, the USB device becomes the A-device. When a Micro-B plug is inserted,

the device becomes the B-device. The OTG A-device behaves similar to a Host while the B-device behaves similar to

a peripheral. The differences are covered in the “On-The-Go Supplement to the USB 2.0 Specification”. In applications

where only USB Host or USB Peripheral is required, the OTG Module is unused.

5.7.1

ID RESISTOR DETECTION

The ID pin of the USB connector is monitored by the ID pin of the USB334x to detect the attachment of different types

of USB devices and cables. For device only applications that do not use the ID signal the ID pin should be connected

to VDD33. The block diagram of the ID detection circuitry is shown in Figure 5-7 and the related parameters are given

in Table 4-9.

FIGURE 5-6:

ULPI START-UP TIMING

DIR

RESETB

STP

TSTART

REFCLK

SUPPLIES

STABLE

PHY Drives Idle

DATA[7:0]

REFCLK valid

PHY Tri-States

PHY Drives High

LINK Drives Low

RXCMD

IDLE

USB334X 数据表(PDF) 32 Page - Microchip Technology