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
SMSC USB251x 61 Revision 1.1 (04-26-10)
DATASHEET
Chapter 9 DC Parameters
9.1 Maximum Guaranteed Ratings
Note 9.1 Stresses above the specified parameters could cause permanent damage to the device.
This is a stress rating only and functional operation of the device at any condition above
those indicated in the operation sections of this specification is not implied.
Note 9.2 When powering this device from laboratory or system power supplies, it is important that
the absolute maximum ratings not be exceeded or device failure can result. Some power
supplies exhibit voltage spikes on their outputs when the AC power is switched on or off.
In addition, voltage transients on the AC power line may appear on the DC output. When
this possibility exists, it is suggested that a clamp circuit be used.
9.2 Operating Conditions
PARAMETER SYMBOL MIN MAX UNITS COMMENTS
Storage
Temperature
T
STOR
-55 150 °C
Lead
Temperature
Refer to JEDEC Specification J-STD-
020D.
3.3 V supply
voltage
VDD33
PLLFILT
CRFILT
4.6 V Applies to all parts.
Voltage on any
I/O pin
-0.5 5.5 V
Voltage on
XTALIN
-0.5 4.0 V
Voltage on
XTALOUT
-0.5 2.5 V
PARAMETER SYMBOL MIN MAX UNITS COMMENTS
Commercial
Operating
Temperature
T
A
070°C
Ambient temperature in still air.
Only applies to USB251x and
USB251xA products.
Extended
Commercial
Operating
Temperature
T
AE
085°C
Ambient temperature in still air.
Only applies to USB251xB products.
Industrial
Operating
Temperature
T
AI
-40 85 °C
Ambient temperature in still air.
Only applies to USB251xi,
USB251xAi, and USB251xBi
products.
3.3 V supply voltage
VDD33 3.0 3.6 V Applies to all parts.
3.3 V supply rise
time
t
RT
0 400 μs See Figure 9.1