IR3082M International Rectifier Corp., IR3082M Datasheet - Page 23

• Manufacturer Part Number: IR3082M
• Description: Xphasetm Amd Opterontm/athlon 64tm Control Ic
• Manufacturer: International Rectifier Corp.

If the over temperature setting voltage is higher than the phase delay setting voltage, VBIAS times RA
connect HOTSET pin between R
R
Bootstrap Capacitor C
Depending on the duty cycle and gate drive current of the phase IC, a 0.1uF to 1uF capacitor is needed for the
bootstrap circuit.
Decoupling Capacitors for Phase IC
0.1uF-1uF decoupling capacitors are required at VCC and VCCL pins of phase ICs.
VOLTAGE LOOP COMPENSATION
The adaptive voltage positioning (AVP is usually used 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 capacitors used. For the applications using Electrolytic, Polymer or AL-Polymer capacitors, type II
compensation shown in Figure 18 (a) is usually enough. While for the applications with only ceramic capacitors,
type III compensation shown in Figure 18 (b) is preferred.
PHASEx3
V O +
V D R P
Page 23 of 23
respectively. Pre-select R
FB
and R
RFB
RDRP
(a) Type II compensation
R
R
R
R
PHASEx
PHASEx
PHASEx
PHASEx
DRP
2
3
2
3
BST
=
=
=
=
are chosen according to Equations (15) and (16), and the selection of compensation types
V
(
(
RA
V
F B
V D A C
RA
V
BIAS
HOTSET
HOTSET
PHASEx
PHASEx
V
⋅
RCP
BIAS
1 (
V
PHASEx1
−
Figure 18. Voltage loop compensation network
−
-
+
⋅
BIAS
⋅
V
⋅
PHASEx1
−
V
R
RA
CCP1
V
RA
BIAS
V
BIAS
PHASEx
BIAS
⋅
E A O U T
PHASEx
HOTSET
PHASEx
1 (
⋅
−
−
−
R
CCP
1
V
and R
V
PHASEx
RA
,
)
HOTSET
HOTSET
⋅
V
PHASEx
BIAS
1
PHASEx2
)
)
⋅
⋅
)
E A O U T
R
R
PHASEx
PHASEx
and connect RMPIN+ or RMPIN- between R
1
1
V O +
V D R P
(b) Type III compensation
RFB1
RFB
RDRP
CFB
F B
V D A C
RCP
(23)
(24)
(25)
(26)
-
+
CCP1
E A O U T
12/17/04
CCP
IR3082
PHASEx2
E A O U T
PHASEx
and
,