SC1544 Datasheet, PDF (1/15 Pages) Semtech Corporation – ACPI Controller for Advanced Motherboards

SC1544
ACPI Controller for
Advanced Motherboards
POWER MANAGEMENT
Description
.eatures
PRELIMINARY
Semtech’s SC1544, SC243x and SC1112A or SC1114
provide all the voltages necessary for an ACPI system.
The SC1544 offers five independant supplies: a 5V dual
supply for USB, a 3.3V dual supply for PCI, a 3.3V or
2.5V dual supply for memory, a 1.5V or 3.3V supply for
AGP and a 1.8V supply. The AGP supply is programmble
using the system TYPEDET signal.
An on-board internal charge pump eliminates the need
for P-channel MOS.ETs and enables function from a single
5V supply (system 5VSB). All dual outputs are over current
protected.
The SC1544 differs from the SC1547 in three important
ways: 1) the device initially starts up in S5, and not G0
like the SC1547; 2) the gate drives for the 1.8V and AGP
outputs are always high in normal operation; 3) no OCP
on the 1.8V and AGP outputs.
Typical Application Circuit
K Complete programmable supply for instantly available
PC systems
K Supports 2.5V memory or 3.3V memory (-2.5 or -3.3
option in part number)
K 5V dual and 3.3V dual supplies are programmable to
be active or inactive in S5
K Integrated AGP voltage supply with “TYPEDET” signal
for 3.3V or 1.5V operation
K Integrated LDO for 1.8V supply
K Integrated charge pump removes the need for PMOS
.ETs, enables single supply operation
K Over current protection on all dual outputs
K Inherent soft-start capability
K TSSOP-24 package
Applications
K Instantly available motherboards
5V
GND
3.3V
GND
5VSB
GND
5V DUAL
GND
3.3V DUAL
GND
3.3V DUAL MEM
GND
AGP
GND
1.8V
GND
TYPEDET
PWR_OK
EN
/SLP_S3
/SLP_S5
USB
PCI
C1
100uF/6.3V
C2
100uF/6.3V
C3
100uF/6.3V
Q1
IRLR3103
Q2
IRLR3103
C4
100uF/6.3V
Q3
IRLR3103
Q4
IRLR3103
C5
100uF/6.3V
Q5
IRLR3103
Q6
IRLR3103
C6
100uF/6.3V
Q7
IRLR3103
C7
100uF/6.3V
Q8
IRLR3103
C8
100uF/6.3V
U1
1
G5
2
3.3VDM
3
G6
4
G7
5
AGP
6
TYPEDET
7
PWR_OK
8
EN
9
/S3
10
/S5
11
USB
12
PCI
SC1544-3.3
24
G8
23
1.8V
22
G4
21
3.3VD
20
GND
19
G2/3
18
G1
17
5VD
16
5VSB
15
FC
14
+CAP
13
-CAP
Revision 3, May 2002
1
C9 0.01uF
C10
C11
0.1uF
1uF
www.semtech.com