ISL6532C Datasheet, PDF (15/16 Pages) Intersil Corporation – ACPI Regulator/Controller for Dual Channel DDR Memory Systems

ISL6532C
MOSFET Selection - AGP LDO
The main criteria for selection of the linear regulator pass
transistor is package selection for efficient removal of heat.
Select a package and heatsink that maintains the junction
temperature below the rating with a maximum expected
ambient temperature.
The power dissipated in the linear regulator is:
P_LINEAR ≅ I_O × (V_IN – V_OUT)
where I_O is the maximum output current and V_OUT is the
nominal output voltage of the linear regulator.
ISL6532C Application Circuit
Figure 8 shows an application circuit utilizing the ISL6532C.
Detailed information on the circuit, including a complete Bill-
of-Materials and circuit board description, can be found in
Application Note AN1056.
+3.3V
R₂
10.0kΩ
PGOOD
V_DDQ
V_REF
C₂₆
0.1µF
SLP_S5
SLP_S3
V_TT
1.25V
V_DDQ
C₂₇
0.1µF
C₁₉
0.47µF
C₂₀ ⁺
220µF
V_DDQ
+ _C21
220µF
Q₄
V_AGP
1.5V
+ _C23
C₂₄
220µF
1µF
R₁₀ 100kΩ
C_{25 680pF}
R₈
249Ω
R₉
287Ω
5VSBY
C_17,18
1µF
VCC12
C₁₆
1µF
PGOOD
S5#
S3#
VREF_OUT
VREF_IN
NCH
OCSET
UGATE
PHASE
ISL6532C
VTT
VTT
VTTSNS
DRIVE2
LGATE
VDDQ
VDDQ
VDDQ
GNDQ
GNDQ
FB
COMP
FB2
R₁
4.99kΩ
VCC5
Q₅
C₂₂ 1000pF
R₇ 8.87kΩ
L₁
2.1µH
C_4,5 ^{+ C}1-3
1µF
2200µF
Q_1,3
L₂
2.1µH
Q_2,4
V_DDQ
2.5V 15A_MAX
+ ^C6-8
1800µF
C_9-12
22µF
R₄
1.74kΩ
C₁₅
1000pF
C₁₃ R₅
56nF 22.6Ω
C₁₄
R₃
6.8nF 19.1kΩ
R₆
825Ω
FIGURE 8. DDR SDRAM AND AGP VOLTAGE REGULATOR USING THE ISL6532C
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