Philips Semiconductors

ISP1103

USB transceiver

Preliminary specification

Rev. 01 — 4 October 1999

4 of 17

9397 750 06329

© Philips Electronics N.V. 1999. All rights reserved.

6.

Functional description

6.1 Function selection

[1]

Signal levels on D

+/D− are determined by other USB devices and external pull-up/down resistors.

[2]

In ‘suspend’ mode (SUSPND = H) the differential receiver is inactive and output RCV is always HIGH.

Out-of-suspend (‘K’) signalling is detected via the single-ended receivers VP and VM.

6.2 Operating functions

[1]

RCV* denotes the signal level on output RCV just before SE0 state occurs. This level is kept stable

during the SE0 period.

D

−

10

AI/O

negative USB data bus connection (analog, differential); for

D

+

11

AI/O

positive USB data bus connection (analog, differential); for

VPO/VO

12

I

differential driver data input (Schmitt trigger); see Table 4

VMO/FSE0

13

I

differential driver data input (Schmitt trigger); see Table 4

14

-

supply voltage (3.0 to 3.6 V)

Table 2:

Symbol

Pin

Type

Description

Table 3:

Function table

SUSPND

OE

D

+/D−

RCV

VP/VM

Function

L

L

driving

active

active

normal driving

(differential receiver active)

L

H

receiving [1]

active

active

receiving

H

L

driving

inactive [2]

active

driving during ‘suspend’

(differential receiver inactive)

H

H

high-Z [1]

inactive [2]

active

low-power state

Table 4:

Driving function (OE = L)

MODE

Interface type

VPO/VO

VMO/FSE0

Data

L

Philips Encoded

Data Interface

L

L

differential logic 0

L

H

SE0

H

L

differential logic 1

H

H

SE0

H

USB-IF Standard

Data Interface

L

L

SE0

L

H

differential logic 0

H

L

differential logic 1

H

H

illegal data

Table 5:

Receiving function (OE=H)

D

+/D−

RCV

VP

VM

differential logic 0

L

L

H

differential logic 1

H

H

L

SE0

RCV*

L

L