Ultra Fast USB 2.0 SD/MMC Flash Media Controller

 

 

 

 

 

Datasheet

 

Table 5.2 USB2244/2244i 36-Pin QFN Pin Descriptions (continued)

 

 

 

 

 

 

 

 

 

36-PIN

BUFFER

 

NAME

 

SYMBOL

QFN

TYPE

DESCRIPTION

 

 

 

 

 

 

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.

 

 

 

 

 

 

 

 

 

DIGITAL / POWER

 

 

 

 

 

 

+1.8V Core

 

VDD18

13

 

All VDD18 pins must be connected together on

power

 

 

 

 

the circuit board.

 

 

 

 

 

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

 

 

 

 

 

(or greater) ±20% (ESR <0.1Ω) capacitor to

 

 

 

 

 

VSS.

 

 

 

 

 

 

3.3V Power &

 

VDD33

6

 

3.3V Power & Regulator Input.

Regulator Input.

 

 

14

 

 

 

 

 

22

 

 

 

 

 

 

 

 

Ground

 

VSS

SLUG

 

Ground Reference

 

 

 

 

 

 

5.2Buffer Type Descriptions

 

Table 5.3 USB2244/USB2244i Buffer Type Descriptions

 

 

BUFFER

DESCRIPTION

 

 

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.

 

 

Revision 1.0 (05-27-08)

12

SMSC USB2244/USB2244i

DATASHEET