LPC47M182 SMSC Corporation, LPC47M182 Datasheet - Page 147

• Manufacturer Part Number: LPC47M182
• Description: ADVANCED I/O CONTROLLER WITH MOTHERBOARD GLUE LOGIC
• Manufacturer: SMSC Corporation

Advanced I/O Controller with Motherboard GLUE Logic
Datasheet
7.39
Note:
SMSC LPC47M182
See Table 13.4 for SCK_BJT_GATE timing.
Backfeed Cut and Latched Backfeed Cut Circuitry
The nBACKFEED_CUT requires an external pull-up to V_5P0_STBY.
nBACKFEED_CUT is a signal required by the S3 power state circuitry and is powered by the VTR supply.
It is a function PWRGD_PS and nSLP_S3 according to the table below. nBACKFEED_CUT is used to
switch between the main voltage regulator and the suspend voltage regulator for various sub-systems
when the system is transitioning into the S3 power state.
nBACKFEED_CUT
LATCHED_BF_CUT
PWRGD_PS
Table 7.42 – nBACKFEED_CUT and LATCHED_BF_CUT Pins
Name
SMSC I/O
MCH
0
0
1
1
Table 7.43 – nBACKFEED_CUT Truth Table
Figure 7.13 - SCK_BJT_GATE Circuit
INPUTS
OD8
OP14
SCK_BJT_GATE
DATASHEET
Buffer
NSLP_S3
V_5P0_STBY
1k
147
Power
0
1
0
1
Well
VTR
VTR
RMB_SCK
Open-Drain Output used for
STR Circuitry
Latched Backfeed Cut Output
for STR Circuitry
Revision 1.8 SMSC/Non-SMSC Register Sets (02-24-05)
nBACKFEED_CUT
Description
OUTPUT
Hi-Z
Hi-Z
Hi-Z
0