cable
USB peripheral controller
USB host
USB host
link
controller
USB
peripheral
link
controller
cable
peripheral device
host device
USB
USB
phy
i/f
phy
i/f
USB
type A
connector
USB
physical
layer:
PHY
or
transceiver
USB
Physical
layer:
PHY
or
transceiver
usb-008
USB
type B
connector
Public Version
www.ti.com
High-Speed USB Host Subsystem
22.2.2 High-Speed USB Host Subsystem Environment
The high-speed USB host controller provides two kinds of interfaces for connection:
•
ULPI interfaces for high-speed data transactions (up to 480M bit/s)
•
Serial interfaces (with the use of the USBTLL module) for full- and low-speed data transactions (up to
12M bit/s)
The high-speed USB host controller connects to either controllers (TLL modes) and/or transceivers. It
supports the following configurations with the serial interfaces and ULPI interfaces:
•
External USB transceiver configurations
–
ULPI interface: 12-pin/8-bit data SDR version
–
Serial 6-pin PHY (transceiver) interfaces: 6-pin mode (TX: DAT/SE0 or TX: DP/DM unidirectional
mode), 4-pin mode (DP/DM bidirectional mode) and 3-pin mode (DAT/SE0 bidirectional mode)
•
TLL configurations
–
ULPI TLL interfaces: 12-pin/8-bit data SDR and 8-pin/4-bit data DDR versions
–
Serial 6-pin TLL interfaces: 6-pin mode (DAT/SE0 and DP/DM unidirectional modes), 4-pin mode
(DP/DM bidirectional mode), 3-pin mode (DAT/SE0 bidirectional mode), and 2-pin mode (DAT/SE0
and DP/DM bidirectional modes)
22.2.2.1 Standard USB Implementation: Transceiver Connection
From a logical point of view, a point-to-point USB connection is composed of several blocks, organized in
protocol layers, and shown in
Figure 22-9. USB Connection
The host system (USB master) and the peripheral system (USB slave) connected through the USB cable
include a link or controller (link layer) and a PHY or transceiver (physical layer). Each system talks to its
own controller, which talks to its own transceiver, which is connected to the opposite side (transceiver)
through an assembly of connectors, receptacles, and cable.
22.2.2.2 TLL Connection
The TLL feature enables connection of the high-speed USB host subsystem to an external, onboard USB
peripheral controller, without using USB transceivers or associated circuitry. When TLL is used, the
following components are removed:
•
Both USB transceivers
•
The series resistors
•
Pullup and pulldown resistors
•
VBUS switching components
•
USB connectors and cables, typically used between a USB host controller and the downstream USB
peripheral controller
The TLL signaling system is not suitable for use across a cable. It is intended only for use when the
device is used with an external USB integrated circuit (IC) that is on the same board.
3237
SWPU177N – December 2009 – Revised November 2010
High-Speed USB Host Subsystem and High-Speed USB OTG Controller
Copyright © 2009–2010, Texas Instruments Incorporated