IR3081AMTR International Rectifier, IR3081AMTR Datasheet - Page 32

• Manufacturer Part Number: IR3081AMTR
• Description: XPHASE VR 10.0 Control IC. The Control IC combined with an IR XPhase TM Phase IC provides a full featured and flexible way to implement a complete VR 10.0 power solution.
• Manufacturer: International Rectifier

Specifications of IR3081AMTR

• Package: 28-Lead MLPQ
• Circuit: X-Phase Controller IC
• Switch Freq (khz): 150kHz to 1.0MHz
• Pbf: PbF Option Available

IR3086A EXTERNAL COMPONENTS
PWM Ramp Resistor R
Set PWM ramp magnitude V
resistor R
Inductor Current Sensing Capacitor C
Choose 47nF for capacitor C
The bias currents of CSIN+ and CSIN- are 0.25uA and 0.4uA respectively. Calculate resistor R
Combined Over Temperature and Phase Delay Setting Resistors R
The over temperature setting resistor divider is combined with the phase delay resistor divider. Set the temperature
threshold at 115 ºC, which corresponds to the IC die temperature of 116 ºC, and calculate the HOTSET threshold
voltage corresponding to the temperature thresholds.
The phase delay resistor ratios for phases 1 to 6 at 800kHz of switching frequencies are RA
RA
slope.
The over temperature setting voltage of phases 1, 2, 5, and 6 is lower than the phase delay setting voltage,
VBIAS*RA
R
R
R
The over temperature setting voltage of Phases 3 and 4 is higher than the phase delay setting voltage,
VBIAS*RA
V
R
R
R
R
R
R
R
CS
HOTSET
PHASE21
PHASE51
PHASE61
PWMRMP
PHASEx
PHASEx
PHASE
CS
PHASE
PHASE2
+
−
Page 32 of 39
=
=
33
32
3
2
L
C
=
. 0
0
=
CS
=
=
=
4 .
=
=
12
25
PWMRMP
R
=10kΩ, R
=10kΩ, R
=10kΩ, R
=0.432, RA
. 4
PHASEx.
V
PHASEx.
(
L
+
V
RA
(
RA
V
V
∗
BIAS
∗
73
IN
=
HOTSET
800
HOTSET
R
PHASE
PHASEx
*
*
100
CS
10
*
V
f
*
+
1 (
SW
BIAS
10
,
−
*
3
Pre-select R
V
Pre-select R
=
3
−
PHASE22
PHASE52
PHASE62
10
∗
∗
*
BIAS
−
3
∗
∗
47
. 0
RA
R
V
C
0
−
V
∗
T
PHASE3
RA
−
V
25
4 .
PHASEx
BIAS
9
V
PWMRMP
100
BIAS
J
*
PHASEx
BIAS
∗
/(
HOTSET
PWMRMP
10
PHASE
+
∗
1 (
0
. 1
*
*
5 .
. 4
−
−
−
=2.94kΩ, R
=2.32kΩ, R
=8.25kΩ, R
10
9
−
R
1
241
22
V
*
CS+,
=0.198, RA
RA
)
PHASE
PWMRMP
V
3
10
HOTSET
−
*
=
HOTSET
*
∗
PHASEX1
PHASE11
[ln(
12
PHASEx
=
10
−
V
. 1
6
3
and Capacitor C
BIAS
and calculate R
. 4
)
8 .
31
∗
3
79
V
. 1
[ln(
=
73
*
IN
=
* )
=
28
∗
. 4
1 (
)
)
=0.75V. Choose 100pF for PWM ramp capacitor C
. 2
*
12
−
12
R
∗
. 0
22
10
−
PHASE23
PHASE53
PHASE63
61
=10kΩ,
=10kΩ,
V
PHASEx
V
R
198
.
PHASE4
CS+
. 0
* 1
O
DAC
−
k
PHASE
−
k
Ω
3
665
. 1
Ω
6
10
∗
∗
) 3
8 .
)
and Resistors R
116
6
1
3
−
)
−
31
8 .
−
=
ln(
=
=4.64kΩ
=4.42kΩ
=6.49kΩ
=0.206, RA
. 1
ln(
∗
+
(
=
. 7
79
CS+,
10
V
. 0
12
. 1
87
. 1 (
PWMRMP
IN
665
*
241
−
k
79
10
−
Ω
1
6
V
∗
3
3 .
8 .
=
−
DAC
6
=
. 0
. 1
−
8 .
∗
. 2
. 0
1 (
198
79
PHASE5
6
−
−
8 .
67
75
. 1
−
V
V
CS+
−
. 0
PWMRMP
79
∗
)]
k
. 1
Ω
. 6
665
)
=
79
) 8
∗
=0.401 and RA
and R
18
10
)
∗
.
10
k 2
)]
*
10
*
PHASEx1,
Ω
10
CS-
3
=
3
12
=
1 .
887
k
R
Ω
PHASE5
Ω
PHASEx2
=0.597 starting from down-
PWMRMP
and R
CS-
PHASEx3
, and calculate the
,
IR3081A
1/31
PHASE1
/05
=0.665,