W83301R Datasheet, PDF (9/16 Pages) Winbond – ACPI-STR Controller

W83301R
Preliminary
7.Functional Description
7.1 Mode Selection
The W83301R supports two modes for customer’s multi-applications, as shown as
Table1, the mode A and mode B can selected via VSET0 pin. If this pin connects to 5V,
the chip will operate under mode A, otherwise the chip will operate under mode B when
VSET0 connects to ground.
Both mode A and B supports a linear switch to generate an ACPI-compliant 5V_DL
voltage from ATX power supply 5V/5V_SB according to S5# and S3# signals. And user
also can turn off the whole 5V_DL output in S5 state via 5V_DLEN# pin if needed.
Under the mode A operation, the chip provide a linear controller STR1 that drives a
N-channel MOSFET Q3 (refer to figure) to generate a regulated voltage 2.5V_DUAL from an
external power source 3.3V_DUAL, the 2.5 V_DUAL is provide for RDRAM/DDRAM ACPI
suspend to RAM application. And In order to simply the circuit design and reduce
customer’s cost, the W83301R also integrate a bus termination controller BT driving two
external N-channel MOSFETs (Q4, Q5) to generate a specific ACPI-compliant voltage
according to a half of STR1 output for sourcing and sinking bus redundant current.
Under the mode B operation, the chip provide three linear controllers, that is STR1-
2.5V_DUAL, STR2- 3.3 V_DUAL, and STR3- 1.8V_DUAL, all of the three outputs drive a N-
channel MOSFET (Q3, Q4, and Q5) to generate an ACPI-compliant voltage by different
applications. Such as STR1- 2.5V_DUAL for clock generator application, STR2- 3.3 V_DUAL
for SDRAM application, and STR3- 1.8V_DUAL chipset application.
Besides, as shown in Table 1 the W83301R also provide a tri-state pin VSET1 to bias
an extra voltage up to 0.2V in each output for more performance but under mode A
operation, the BT output voltage will generated according to a half of STR1 output set by
VSET1.
Table 1. W83301R Control Table
Mode VSET0 VSET1
0V
0V
A
0V
NC
0V
5V
Mode VSET0 VSET1
5V
5V
B
5V
NC
5V
0V
STR1
2.5V_DUAL
2.6V_DUAL
2.7V_DUAL
STR1
2.5V_DUAL
2.6V_DUAL
2.7V_DUAL
Bus Termination Controller
Remark
1.25V_DUAL
1.30V_DUAL
1.35V_DUAL
STR2
STR3
-STR1 output for RDRAM/DDRAM voltage
-Bus Termination Controller for memory bus
redundant current sinking and sourcing.
Remark
3.3V_DUAL
3.4V_DUAL
3.5V_DUAL
1.8V_DUAL
1.8V_DUAL
1.8V_DUAL
-STR1 output for Clock Gen. voltage
-STR2 output for SDRAM voltage
-STR3 output for Chipset voltage
Confidential
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Revision 0.6