Datasheet
Table Of Contents
- Chapter 1 USB251x Hub Family Differences Overview
- Chapter 2 General Description
- Chapter 3 Acronyms
- Chapter 4 Block Diagram
- Chapter 5 Pin Descriptions
- Chapter 6 LED Usage Description
- Chapter 7 Battery Charging Support
- Chapter 8 Configuration Options
- Chapter 9 DC Parameters
- 9.1 Maximum Guaranteed Ratings
- 9.2 Operating Conditions
- Figure 9.1 Supply Rise Time Model
- Table 9.1 DC Electrical Characteristics (continued)
- Table 9.2 Supply Current Unconfigured: Hi-Speed Host (ICCINTHS)
- Table 9.3 Supply Current Unconfigured: Full-Speed Host (ICCINTFS)
- Table 9.4 Supply Current Configured: Hi-Speed Host (IHCH1)
- Table 9.5 Supply Current Configured: Full-Speed Host (IFCC1)
- Table 9.6 USB251x/xi/xA/xAi Supply Current Suspend (ICSBY)
- Table 9.7 USB251xB/xBi Supply Current Suspend (ICSBY)
- Table 9.8 USB251x/xi/xA/xAi Supply Current Reset (ICRST)
- Table 9.9 USB251xB/xBi Supply Current Reset (ICRST)
- Table 9.10 Pin Capacitance for USB251x, USB251xi, USB251xA, USB251xAi
- Table 9.11 Pin Capacitance for USB251xB and USB251xBi
- 9.2.1 Package Thermal Specifications
- Chapter 10 AC Specifications
- Chapter 11 Package Outlines

USB 2.0 Hi-Speed Hub Controller
Datasheet
Revision 1.1 (04-26-10) 62 SMSC USB251x
DATASHEET
Figure 9.1 Supply Rise Time Model
Voltage on any I/O
pin
-0.3 5.5 V If any 3.3 V supply voltage drops
below 3.0 V, then the MAX becomes:
(3.3 V supply voltage) + 0.5
Voltage on XTALIN -0.3 VDD33 V
Table 9.1 DC Electrical Characteristics
PARAMETER SYMBOL MIN TYP MAX UNITS COMMENTS
I, IS Type Input Buffer
Low Input Level
High Input Level
Input Leakage
Hysteresis (‘IS’ Only)
V
ILI
V
IHI
I
IL
V
HYSI
2.0
-10
250
0.8
+10
350
V
V
μA
mV
TTL Levels
V
IN
= 0 to VDD33
Input Buffer with Pull-Up (IPU)
Low Input Level
High Input Level
Low Input Leakage
High Input Leakage
V
ILI
V
IHI
I
ILL
I
IHL
2.0
+35
-10
0.8
+90
+10
V
V
μA
μA
TTL Levels
V
IN
= 0
V
IN
= VDD33
Input Buffer with Pull-Down (IPD)
Low Input Level
High Input Level
Low Input Leakage
High Input Leakage
V
ILI
V
IHI
I
ILL
I
IHL
2.0
+10
-35
0.8
-10
-90
V
V
μA
μA
TTL Levels
V
IN
= 0
V
IN
= VDD33
PARAMETER SYMBOL MIN MAX UNITS COMMENTS
t
10%
10%
90%
Voltage
t
RT
t
90%
Time
100%
3.3 V
VSS
VDD33