ISL6523 Datasheet, PDF (15/16 Pages) Intersil Corporation – VRM8.5 Dual PWM and Dual Linear Power System Controller

ISL6523
ISL6523 DC-DC Converter Application
Circuit
Figure 13 shows an application circuit of a power supply for a
microprocessor computer system. The power supply
provides the microprocessor core voltage (V_OUT1), the AGP
bus voltage (V_OUT2), the GTL bus voltage (V_OUT3), and the
memory controller hub voltage (V_OUT4) from +3.3V, +5VDC,
and +12VDC. For detailed information on the circuit,
including a Bill-of-Materials and circuit board description,
see Application Note AN9925. Also see the Intersil web page
(www.intersil.com) for the latest information.
+5V
+12V
+3.3V
L1
1µH
+ _C1
680µF
GND
GND
GND
V_OUT2 (VTT)
+1.2V
Q3
HUF76121
L2
2.0µH
+
C7
1000µF
R7
10kΩ
VTT
POWER GOOD
Q4
HUF76107
V_OUT3 (AGP)
+1.5V
+ _C18
560µF
Q5
2SD1802
V_OUT4 (MCH)
+1.8V
+ _C21
560µF
C2
C3
1µF
1nF
R2
10
2.2kΩ ^OCSET2
VCC
28
UGATE2
1
2
PHASE2
CR1
HSM835
VSEN2
11
C15 ⁺
10µF
VTTPG
9
VAUX
16
U1
ISL6523
DRIVE3
18
VSEN3
19
DRIVE4
15
VSEN4
14
17
GND
C5
C4
1µF
1nF
R3
23
OCSET1 1.5kΩ
8
PGOOD
R1
10kΩ
POWER GOOD
27 ^UGATE1
26
PHASE1
25 ^LGATE1
Q1
HUF76139
L3
Q2
HUF76143
1.8µH
V_OUT1 (CORE)
+1.050V TO 1.825V
+ _C8-10
3x1000µF
24 ^PGND
R5
4.99kΩ
22 ^VSEN1
21 ^FB1
R8
3.32kΩ
COMP1
20
C13
270pF
C14 R10
C16 R11
22nF 33Ω
C12
0.30µF
R9
12.1k
2.2nF 43kΩ
R12
267kΩ
VID25
7
6 ^VID0
5 ^VID1
4 ^VID2
VID3
3
12 ^SS24
SS13
13
C22
0.1µF
C19
0.1µF
FIGURE 13.
15