NCP5222 ON Semiconductor, NCP5222 Datasheet - Page 13

• Manufacturer Part Number: NCP5222
• Description: High Performance Dual-channel / Two-phase Synchronous Buck Controller For Notebook Power System
• Manufacturer: ON Semiconductor

output regulation control as what is in the dual−channel
operation. The output voltage is
the output voltage in phase 2 is adjusted to be higher or lower
than V
means of an injection current I
amplifier’s non−inverting node. Thus output voltage of the
phase 2 is
between the two current−sense output signals V
V
I
ICS1
FB2
In the two−phase operation, the phase 1 has the same
However, in order to achieve current−sharing function,
The injection current I
V
V
+ G
+ 1x10
+ 1x10
+ 1x10
O1
, that is
O1
O2
+ 1 )
to balance the power delivery in the two phases, by
+ 1 )
+ 1 )
IFB2
−3
−3
−4
@ V
@ V
@ k
@ V
R
R
ICS2
R
R
R
R
11
14
CS2
ICS2
ICS2
21
24
21
24
* V
@ V
@ DCR
FB2
* V
@ V
@ 0.8 * I
* V
R14
R24
ref1
ICS1
ref2
is proportional to the difference
ICS1
ICS1
+ 1 )
2
* I
Figure 10. PWM Output Regulation in Two−Phase Mode
@ I
FB2
R11
R21
FB2
FB1
FB2
L2
FB2
into the phase 2 error
IFB2
* k
@ R
0.8V
0.8V
@ R
R
R
21
CS1
11
14
21
@ DCR
@ 0.8
G
m
COMP1
COMP2
ICS2
1
(eq. 6)
(eq. 7)
(eq. 8)
http://onsemi.com
ICS1
ICS2
@ I
and
L1
PWM1
PWM2
Rics1
Rics2
20k
20k
13
SWN1
SWN2
where
and
the current distribution in the two phases can be calculated
by
and
Based on understanding of the power stage connection,
G
G
i
i
V
V
V
V
k
k
1.25V
Rcs11
Rcs21
CS1+
CS1−
CS2−
CS2+
ICS1
ICS2
CS1
CS2
CS1
CS2
+ k
+ k
+
+
+ G
+ 10 @ V
+ G
+ 10 @ V
L1
L2
R
R
Rcs12
Rcs22
Ccs1
Ccs2
CS1
CS2
CS11
CS21
ICS1
ICS2
R
R
@ I
@ I
CS12
CS22
) R
) R
@ R
CS1
@ R
CS2
I
I
L1
L2
Vo1
Vo2
L1
L2
@ DCR
@ DCR
ICS1
ICS2
) 1.25
) 1.25
+ I
+ I
CS12
CS22
Ssh
C1
C2
O1
O2
@ V
@ V
IL1
IL2
1
2
* I
* I
CS1
CS2
ISH
Share
Share
Io1
Io2
) V
) V
ICS_Offset
ICS_Offset
(eq. 10)
(eq. 12)
(eq. 13)
(eq. 14)
(eq. 15)
(eq. 16)
(eq. 11)
(eq. 9)