L6911D View Datasheet(PDF) - STMicroelectronics
Part Name
Description
MFG CO.
'L6911D' PDF : 17 Pages View PDF
L6911D
Figure 9. Voltage regulation with droop function block scheme
Vcomp
Av(s)
Vout
R (s )
R OUT ⋅ 1 + s ⋅ τ L
1+ s ⋅τd
Iout
It results:
ZOUT
=
-----V----o------
ILOAD
=
Rd
⋅
1-1----++-----ss----ττ--Ld--
⋅
-----G-----L---O----O----P-------
1 + GLOOP
=
ROUT ⋅ 11-----++-----ss----ττ--Ld--
Because in the interested range |Gloop|>>1.
To obtain a flat shape, the relationship considered will naturally follow.
Application Idea: 1.100V to 1.850V / 25A
Figure 10 shows an application schematic for a 1.100V to 1.850V conversion with 25A of current capability.
Since the device's high gate drive, more than one mosfet for both high side and low side can be used: three
STS11NF30L (30V, 9mW typ @ Vgs=10V) mosfet are suggested for high side while four of them are suggested
as low side switch.
Figure 10. Schematic Circuit
+5 VIN
F1
L1
+12Vcc
VID0
VID1
VID2
VID3
VID25mV
R10
C17
D1
VCC
BOOT
15
18
OVP
19
2
C24
OCSET
GND
11
VID0
4
VID1
5
VID2
6
VID3
7
VID4
8
R1 OSC
20
UGATE
14
PHASE
13
U1
LGATE
L6911D 17
PGND
16
PGOOD
12
SS
3
VSEN
1
C16
9
10
COMP
VFB
C18
R3
C23
R7
R13
Q1,Q2, Q3
R14
Q4,Q5,Q6
C19 R5
C20
R4
R2
C1-3
C21-22
L2
VOUTCORE
D2
C4-9
R15 R6
Vss
PWRGD
R8
R9
C17
14/17
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