SMSC USB2250i Manual Do Utilizador

Ultra Fast USB 2.0 Multi-Slot Flash Media Controller

SMSC USB2250/50i/51/51i

19

Revision 1.1 (05-29-08)

1. Hot-insertion capable card connectors are required for all flash media. It is required for the SD

connector to have a Write Protect switch. This allows the chip to detect the MMC card. 

2. nMCE is normally asserted except when the 8051 is in standby mode.

3. Refer to PWR_MGMT_CTL1 register for controlling pull-up / down resistors associated with the

pins as well as the individual card control registers.

1.8V Digital Core 
Power

VDD18

49

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

+1.8V Core power. If the internal regulator is 
enabled, then this pin must have a 1.0

μ

F (or 

greater) ±20% (ESR <0.1

Ω) capacitor to 

VSS.

3.3V Power & 
Voltage 
Regulator Input

VDD33

15
50
65
77

104

3.3V Power & Voltage Regulator Input

Ground

VSS

9

17
51
75
81

102
122
126

Ground Reference.