PDIUSBD11 Datasheet, PDF (3/20 Pages) NXP Semiconductors – USB device with serial interface

Philips Semiconductors
USB device with serial interface
Product specification
PDIUSBD11
Analog Transceiver
The transceiver interfaces directly to the USB cables through some
termination resistors. They are capable of transmitting and receiving
serial data at “full speed” (12 Mbit/s) only.
PLL
A 12 MHz to 48 MHz clock multiplier PLL (Phase-Locked Loop) is
integrated on-chip. This allows for the use of low-cost 12 MHz
crystal. EMI is also minimized due to lower frequency crystal. No
external components are needed for the operation of the PLL.
Bit Clock Recovery
The bit clock recovery circuit recovers the clock from the incoming
USB data stream using 4X over-sampling principle. It is able to track
jitter and frequency drift specified by the USB specification.
Philips Serial Interface Engine (PSIE)
The Philips SIE implements the full USB protocol layer. It is
completely hardwired for speed and needs no firmware intervention.
The functions of this block include: synchronization pattern
recognition, parallel/serial conversion, bit stuffing/de-stuffing, CRC
checking/generation, PID verification/generation, address
recognition, handshake evaluation/generation.
Memory Management Unit (MMU) and Integrated
RAM
The MMU and the integrated RAM is used to handle the large
difference in data rate between USB, running in bursts of 12 Mbit/s
and the I²C interface to the microcontroller, running at up to 1 Mbit/s.
This allows the microcontroller to read and write USB packets at its
own speed through I²C.
I²C Slave Interface
This block implements the necessary I²C interface protocol. A slave
I²C allows for simple micro-coding. An interrupt is used to alert the
microcontroller whenever the PDIUSBD11 needs attention. As a
slave I²C device, the PDIUSBD11 I²C clock: SCL is an input and is
controlled by the microcontroller. The I²C interface can run up to
1 Mbit/s.
SoftConnect™
The connection to the USB is accomplished by bringing D+ (for
high-speed USB device) high through a 1.5 kW pull-up resistor. In
the PDIUSBD11, the 1.5 kW pull-up resistor is integrated on-chip
and is not connected to V_CC by default. The connection of the
internal resistor to Vcc is established through a command sent by
the external/system microcontroller. This allows the system
microcontroller to complete its initialization sequence before
deciding to establish connection to the USB. Re-initialization of the
USB bus connection can also be affected without requiring the pull
out of the cable.
The PDIUSBD11 will check for USB VBUS availability before the
connection can be established. VBUS sensing is provided through
VBUS pin.
It should be noted that the tolerance of the internal resistors is
higher (30%) than that specified by the USB specification (5%).
However, the overall V_SE voltage specification for the connection
can still be met with good margin. The decision to make sure of this
feature lies with the users.
SoftConnect™ is a patent pending technology from Philips
Semiconductors.
ENDPOINT DESCRIPTIONS
ENDPOINT#
ENDPOINT INDEX
2
0
3
5
1
4
6
2
7
8
3
9
NOTE:
1. Generic endpoint can be used for Interrupt or Bulk endpoint.
TRANSFER TYPE
Control
Generic
Generic
Generic
DIRECTION
OUT
IN
OUT
IN
OUT
IN
OUT
IN
MAX
PACKET SIZE
(BYTES)
8
8
8
8
8
8
8
8
1999 Jul 22
3