Document Number: 001-65659 Rev. *I Page 18 of 26
AC Electrical Characteristics
USB Transceiver is USB 2.0 certified in low, full and high speed modes.
Both the upstream USB transceiver and all four downstream transceivers have passed the USB-IF USB 2.0 Electrical Certification
Testing.
The 48-pin TQFP package can support communication to EEPROM using either I
2
C or SPI. The 28-pin QFN package can support
only I
2
C communication to EEPROM.
AC characteristics of these two interfaces to EEPROM are summarized in tables below:
AC Characteristics of SPI EEPROM interface
Parameter Parameter Min Typ Max Units
t
CSS
CS setup time 3.0 – –
µs
t
CSH
CS hold time 3.0 – –
t
SKH
SK high time 1.0 – –
t
SKL
SK low time 2.2 – –
t
DIS
DI setup time 1.8 – –
t
DIH
DI hold time 2.4 – –
t
PD1
Output delay to ‘1’ – – 1.8
t
PD0
Output delay to ‘0’ – – 1.8
AC Characteristics of I
2
C EEPROM interface
Parameter Parameter
1.8 V–5.5 V 2.5 V–5.5 V
Units
Min Max Min Max
f
SCL
SCL clock frequency 0.0 100 0.0 400 KHz
t
LOW
Clock LOW Period 4.7 – 1.2 – us
t
HIGH
Clock HIGH Period 4.0 – 0.6 – us
t
SU:STA
Start condition setup time 4.7 – 0.6 – us
t
SU:STO
Stop condition setup time 4.7 – 0.6 – us
t
HD:STA
Start condition hold time 4.0 – 0.6 – us
t
HD:STO
Stop condition hold time 4.0 – 0.6 – us
t
SU:DAT
Data in setup time 200.0 – 100.0 – ns
t
HD:DAT
Data in hold time 0 – 0 – ns
t
DH
Data out hold time 100 – 50 – ns
t
AA
Clock to output 0.1 4.5 0.1 – us
t
WR
Write cycle time – 10 – 5 ns
Thermal Resistance
Parameter Description
48-pin TQFP
Package
28-pin QFN
Package
Unit
JA
Thermal resistance (junction to ambient) 78.7 33.3 °C/W
JC
Thermal resistance (junction to case) 35.3 18.4 °C/W