ISP1581BD NXP Semiconductors, ISP1581BD Datasheet - Page 13

• Manufacturer Part Number: ISP1581BD
• Manufacturer: NXP Semiconductors

Specifications of ISP1581BD

• Operating Temperature (max): 85C
• Operating Temperature (min): -40C
• Operating Temperature Classification: Industrial
• Lead Free Status / RoHS Status: Compliant

Philips Semiconductors
9397 750 13462
Product data
7.3.1 Philips Parallel Interface Engine
7.3.2 Peripheral circuit
7.3.3 HS detection
7.1 Hi-Speed USB transceiver
7.2 Philips Serial Interface Engine (SIE)
7.3 Philips HS (High-Speed) Transceiver
The analog transceiver interfaces directly to the USB cable via integrated termination
resistors. The high-speed transceiver requires an external resistor (12.0 k
between pin RREF and ground to ensure an accurate current mirror that is used to
generate the Hi-Speed USB current drive. A full-speed transceiver is integrated as
well. This makes the ISP1581 compliant with Hi-Speed USB and Original USB,
supporting both the high-speed and full-speed physical layer. After automatic speed
detection, the Philips Serial Interface Engine sets the transceiver to use either
high-speed or full-speed signaling.
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 (de-)stuffing, CRC
checking/generation, Packet IDentifier (PID) verification/generation, address
recognition, handshake evaluation/generation.
In the HS Transceiver, the Philips PIE interface uses a 16 bit Parallel bi-directional
data interface. The functions of the HS (High-speed) module also include
Bit-stuffing/De-stuffing and NRZI Encoding/Decoding logic.
To maintain a constant current driver for HS (High-Speed) transmit circuits and to bias
other analog circuits, an internal band-gap reference circuit and RREF resistor are
used to form the reference current. This circuit requires an external precision resistor
(12.0 k
ISP1581 handles more than one electrical state (FS/HS) under the USB
specification. When the USB cable is connected from the device to the host
controller, at first the device ISP1581 defaults to the Full-speed (FS) state until it sees
a bus reset from the host controller.
During the bus reset, the device initiates a HS chirp to detect whether the
host-controller supports Hi-Speed USB or Original USB. Chirping must be done with
the pull-up resistor connected and the internal termination resistors disabled. If the
HS handshake shows that there is a HS host connected, then ISP1581 switches to
the HS state.
In HS state, the ISP1581 observes the bus for periodic activity. If the bus remains
inactive for 3 ms, the device switches to the FS state to check for an
SE0 (Single-ended zero) condition on the USB bus. If an SE0 condition is detected
for the designated time window (100 s to 875 s, see Section 7.1.7.6 of the USB
specification Rev. 2.0), the ISP1581 switches to the HS chirp state again to do a HS
detection handshake. Otherwise, the ISP1581 remains in the FS state adhering to the
bus-suspend specification.
1%) connected to analog ground.
Rev. 06 — 23 December 2004
Hi-Speed USB peripheral controller
© Koninklijke Philips Electronics N.V. 2004. All rights reserved.
ISP1581
1%)
12 of 79