ir3082pbf International Rectifier Corp., ir3082pbf Datasheet - Page 26

• Manufacturer Part Number: ir3082pbf
• Description: Xphase Amd Opterontm/athlon 64tm Control Ic
• Manufacturer: International Rectifier Corp.

From Figure 15, the source current of VDAC pin is 170uA. The VDAC up-slope slew rate is
Over Current Setting Resistor R
The room temperature is 25ºC and the target PCB temperature is 100 ºC. The phase IC die temperature is about 1
ºC higher than that of phase IC, and the inductor temperature is close to PCB temperature.
Calculate Inductor DC resistance at 100 ºC,
The current sense amplifier gain is 34 at 25ºC, and its gain at 101ºC is calculated as,
Set the over current limit at 115A. From Figure 14, the bias current of OCSET pin (I
R
the current sense amplifier input resistor mismatch.
Calculate constant K
No Load Output Voltage Setting Resistor R
From Figure 14, the bias current of FB pin is 65uA with R
Select RFB = 232 Ω.
G
SR
R
K
R
R
R
L
OSC
OCSET
DRP
CS
FB
P
_
UP
MAX
_
=
=
MIN
=
=18.2kΩ. The total current sense amplifier input offset voltage is 0.6mV, which includes the offset created by
=
(
V
=
=
R
=
R
I
I
Page 26 of 33
C
[
(
L
SOURCE
=
FB
R
115
−
R
VDAC
_
L
G
5
LIMIT
MAX
⋅
V
_
n
R
CS
ROOM
O
L
⋅
)
_
. 0
_
⋅
n
⋅
=
ROOM
⋅
MAX
V
I
V
54
⋅
R
⋅
LIMIT
O
170
1 [
O
R
47
L
⋅
O
_
/(
_
⋅
+
10
I
MAX
NLOFST
G
⋅
⋅
L
3850
⋅
1 [
FB
10
P,
/
CS
10
⋅
−
n
V
3
−
the ratio of inductor peak current over average current in each phase,
−
⋅
_
⋅
−
⋅
I
9
1470
1 (
MIN
6
. 1
R
⋅
⋅
10
+
−
L
=
147
f
_
SW
−
K
V
=
3
6
MAX
⋅
6 .
CS
⋅
10
P
232
⋅
+
(
)
mV
T
) 2
_
+
0
L
−
TOFST
6
_
6 .
V
=
⋅
5
MAX
⋅
OCSET
CS
. 0
/
(
⋅
⋅
(
uS
T
10
. 0
12
54
_
IC
−
TOFST
75
⋅
−
_
⋅
T
−
n
3
10
MAX
ROOM
)
⋅
. 1
⋅
10
⋅
R
−
]
335
30
3
⋅
−
O
−
G
⋅
3
)]
2 .
30
T
)
CS
=
=
⋅
ROOM
/(
FB
2 .
. 1
_
. 0
. 0
65
MIN
335
42
=
54
and Adaptive Voltage Positioning Resistor R
⋅
. 1
)]
10
⋅
/
10
⋅
/(
01
I
=
10
115
OCSET
−
220
−
6
k
3
34
−
Ω
)
⋅
3
1 [
=
5 /
⋅
⋅
OSC
⋅
1 [
10
+
15
. 6
3850
−
65
−
k 9
1470
9
⋅
=18.2kΩ.
10
⋅
⋅
Ω
12
10
⋅
10
−
3
⋅
⋅
−
600
10
6
−
−
6
⋅
⋅
−
0
. 0
(
6
100
⋅
6 .
10
⋅
54
(
⋅
101
3
10
−
⋅
⋅
10
25
) 2
−
−
3
)]
−
25
=
⋅
3
=
5
. 0
)]
. 0
⋅
147
. 0
=
54
75
30
m
Ω
2 .
⋅
10
−
3
IR3082PbF
=
230
OCSET
01/31/05
DRP
Ω
) is 65uA with