SMSC USB2244 Manual De Usuario

Ultra Fast USB 2.0 SD/MMC Flash Media Controller

Revision 1.0 (05-27-08)

12

SMSC USB2244/USB2244i

TEST Input

TEST

28

I

This signal is used for testing the chip. User 
should normally tie this pin low externally if the 
test function is not used.

No Connects

NC

No Connect. No trace or signal should be 
routed/attached to these pins.

+1.8V Core 
power

VDD18

13

All VDD18 pins must be connected together on 
the circuit board.

+1.8V core power. This pin must have a 1.0

μ

F 

(or greater) ±20% (ESR <0.1

Ω) capacitor to 

VSS.

3.3V Power & 
Regulator Input.

VDD33

6

14
22

3.3V Power & Regulator Input.

Ground

VSS

SLUG

Ground Reference

I

Input.

IS

Input with Schmitt trigger.

I/O12

Input/Output buffer with 12mA sink and 12mA source.

I/O200

Input/Output buffer 12mA with FET disabled, 100/200mA source only when the FET is 
enabled.

I/O12PU

Input/Output buffer with 12mA sink and 12mA source with a pull-up resistor.

O12

Output buffer with 12mA source.

ICLKx

XTAL clock input.

OCLKx

XTAL clock output.

I/O-U

Analog Input/Output Defined in USB specification.

I-R

RBIAS.