IR3086AMTRPBF International Rectifier, IR3086AMTRPBF Datasheet - Page 18
![IC CTLR XPHASE 28-MLPQ](/photos/7/48/74806/20_mlpq_sml.jpg)
IR3086AMTRPBF
Manufacturer Part Number
IR3086AMTRPBF
Description
IC CTLR XPHASE 28-MLPQ
Manufacturer
International Rectifier
Series
XPhase™r
Datasheets
1.IR3086AMTRPBF.pdf
(33 pages)
2.IR3086AMTRPBF.pdf
(33 pages)
3.IR3086AMTRPBF.pdf
(33 pages)
Specifications of IR3086AMTRPBF
Package / Case
20-MLPQ
Mounting Type
Surface Mount
Current - Supply
10mA
Voltage - Supply
8.4 V ~ 14 V
Operating Temperature
0°C ~ 125°C
Applications
Processor
Package
20-Lead MLPQ
Circuit
X-Phase Phase IC
Iout (a)
2.5A Gate Driver
Pbf
PbF Option Available
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
VOLTAGE LOOP COMPENSATION
The adaptive voltage positioning (AVP) is usually adopted in the computer applications to improve the transient
response and reduce the power loss at heavy load. Like current mode control, the adaptive voltage positioning loop
introduces extra zero to the voltage loop and splits the double poles of the power stage, which make the voltage
loop compensation much easier.
Resistors R
depends on the output capacitors used in the converter. For the applications using Electrolytic, Polymer or AL-
Polymer capacitors and running at lower frequency, type II compensation shown in Figure 8(a) is usually enough.
While for the applications using only ceramic capacitors and running at higher frequency, type III compensation
shown in Figure 8(b) is preferred.
For applications where AVP is not required, the compensation is the same as for the regular voltage mode control.
For converter using Polymer, AL-Polymer, and ceramic capacitors, which have much higher ESR zero frequency,
type III compensation is required as shown in Figure 8(b) with R
Type II Compensation for AVP Applications
Determine the compensation at no load, the worst case condition. Choose the crossover frequency fc between 1/10
and 1/5 of the switching frequency per phase. Assume the time constant of the resistor and capacitor across the
output inductors matches that of the inductor, and determine R
and C
respectively.
C
ceramic capacitor between 10pF and 220pF is usually enough.
Type III Compensation for AVP Applications
Determine the compensation at no load, the worst case condition. Assume the time constant of the resistor and
capacitor across the output inductors matches that of the inductor, the crossover frequency and phase margin of the
voltage loop can be estimated by Equations (27) and (28), where R
CP1
is optional and may be needed in some applications to reduce the jitter caused by the high frequency noise. A
VO+
VDRP
E
Page 18 of 33
are the equivalent inductance of output inductors and the equivalent capacitance of output capacitors
FB
and R
RFB
RDRP
(a) Type II compensation
C
R
f
DRP
C
CP
CP
1
=
=
=
are chosen according to Equations (13) and (14), and the selection of compensation types
2
2 (
10
π
VDAC
π
*
∗
FB
FB
∗
V
C
RCP
O
R
E
f
L
C
CP
*
∗
E
)
G
2
R
+
Figure 8. Voltage loop compensation network
∗
-
CCP1
1
CS
∗
DRP
C
+
L
E
*
2 (
EAOUT
E
R
∗
π
FB
C
CCP
*
E
∗
f
∗
C
R
R
*
LE
FB
C
*
∗
EAOUT
R
V
C
PWMRMP
)
2
VO+
VDRP
RFB1
CP
DRP
(b) Type III compensation
and C
LE
RFB
RDRP
and C
CFB
CDRP
is the equivalent resistance of inductor DCR.
CP
DRP
from Equations (25) and (26), where L
VDAC
removed.
FB
RCP
+
-
CCP1
EAOUT
CCP
(25)
(26)
(27)
IR3086A
EAOUT
1/31
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E