Industrial Temperature Rated USB 2.0 Hi-Speed 2-Port Hub Controller

 

 

 

Datasheet

 

Table 3.1 USB2512Ai Pin Descriptions (continued)

 

 

 

 

 

QFN-36

BUFFER

 

SYMBOL

EMB

TYPE

DESCRIPTION

 

 

 

 

XTAL2

32

OCLKx

Crystal Output

 

 

 

24MHz Crystal

 

 

 

This is the other terminal of the crystal, or a NO CONNECT

 

 

 

when an external clock source is used to drive XTAL1/CLKIN.

 

 

 

Note: This output must not be used to drive any external

 

 

 

circuitry other than the crystal circuit.

 

 

 

 

RESET_N

26

IS

RESET Input

 

 

 

The system can reset the chip by driving this input low. The

 

 

 

minimum active low pulse is 1 μs.

 

 

 

When the RESET_N pin is pulled to VDD33, the internal POR

 

 

 

(Power-on Reset) is enabled and no external reset circuitry is

 

 

 

required. The internal POR holds the internal logic in reset until

 

 

 

the power supplies are stable.

 

 

 

 

SUSP_IND/

28

I/O

Active/Suspend status LED or Local-Power & Non-removable

LOCAL_PWR/

 

 

Strap Option

NON_REM0

 

 

Suspend Indicator: Indicates USB state of the Hub.

 

 

 

 

 

 

‘negated’ = Unconfigured, or configured and in USB Suspend

 

 

 

‘asserted’ = Hub is configured, and is active (i.e., not in

 

 

 

suspend)

 

 

 

 

 

 

 

Local Power: Detects availability of local self-power source.

 

 

 

Low = Self/local power source is NOT available (i.e., Hub gets

 

 

 

all power from Upstream USB VBus).

 

 

 

High = Self/local power source is available.

 

 

 

NON_REM0 Strap Option:

 

 

 

If this strap is enabled by package and configuration settings

 

 

 

(see Table 3.2, "SMBus or EEPROM Interface Behavior"), this

 

 

 

pin will be sampled (in conjunction with NON_REM1) at

 

 

 

RESET_N negation to determine if ports [2:1] contain

 

 

 

permanently attached (non-removable) devices. Also, the

 

 

 

active state of the LED will be determined as follows:

 

 

 

NON_REM[1:0] = ‘00’, All ports are removable, and the LED is

 

 

 

active high

 

 

 

NON_REM[1:0] = ‘01’, Port 1 is non-removable, and the LED

 

 

 

is active low

 

 

 

NON_REM[1:0] = ‘10’, Ports 1 & 2 are non-removable, and the

 

 

 

LED is active high

 

 

 

NON_REM[1:0] = ‘11’, Ports 1 & 2 are non-removable, and the

 

 

 

LED is active low

 

 

 

 

TEST

11

IPD

TEST pin

 

 

 

XNOR continuity tests all signal pins on the Hub. Please

 

 

 

contact your SMSC representative for a detailed description of

 

 

 

how this test mode is enabled and utilized.

 

 

 

 

Revision 1.97 (08-11-08)

10

SMSC USB2512Ai

 

DATASHEET