3.3v I/O Controller for Port Replicators and Docking Stations
4.2
Pins That Require External Resistors
The following pins require external pull-up resistors:
LAD[3:0]
nLDRQ
SER_IRQ
nCLKRUN
nIO_PME if used as Open Drain Output
nALF if used as Open Drain Output
nSTROBE if used as Open Drain Output
nINIT if used as Open Drain Output
nSLCTIN if used as Open Drain Output
SMB_A0 – this pin has weak internal pull-down. External pull-up can be used to change the LSB of
SMBus device address.
SDAT
SCLK
nSMBINT
SDAT_1
SCLK_1
SDAT_2
SCLK_2
The following pin requires external pull-up/pull-down resistor:
LGP47 (SYSOPT) – pull-up or pull-down is required for SYSOPT strap option to set system base IO
address.
GPIOs
SMSC DS – LPC47N237
Page 19
DATASHEET
Revision 0.3 (10-26-04)