IR3500MPBF International Rectifier, IR3500MPBF Datasheet - Page 36

• Manufacturer Part Number: IR3500MPBF
• Description: IC XPHASE3 CONTROL 32-MLPQ
• Manufacturer: International Rectifier
• Series: XPhase3™r

Specifications of IR3500MPBF

• Applications: Processor
• Current - Supply: 6.5mA
• Voltage - Supply: 4.75 V ~ 7.5 V
• Operating Temperature: 0°C ~ 100°C
• Mounting Type: Surface Mount
• Package / Case: 32-MLPQ
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The soft start delay time is
The VR ready delay time is
The minimum over current fault latch delay time is
VDAC Slew Rate Programming Capacitor C
Calculate the VDAC down-slope slew-rate programming capacitor from the required down-slope slew rate. The
up-slope slew rate is the same as the down-slope slew rate.
Calculate the programming resistor.
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,
Set the over current limit at 135A. From Figure 24, the bias current of OCSET pin (I
R
the current sense amplifier (CSA) input bias current through the resistor R
Calculate constant K
V
TD
TD
t
C
R
R
K
R
OCDEL
VDAC
OSC
L
VDAC
CS
P
OCSET
_
1
3
=
MAX
_
=
=
TOFST



=50k . The total current sense amplifier input offset voltage is 0.3mV, which includes the offset created by
V
C
=
C
=
I
=
=
=
SS
Page 36 of 47
SS
0
⋅
=
SR
D
5 .
(
R
[
C
/
I
I
/
I
(
DEL
L
=
I
CHG
DEL
⋅
LIMIT
SINK
+
DOWN
135
SS
_
1 (
LIMIT
0
n
ROOM
3
3
I
I
/
−
1 *
2 .
3 .
CHG
DEL
C
*
DISCHG
/
D
n
VDAC
4 (
*
mV
∗
4 .
)
)
∗
=
10
⋅
0 .
. 1
∗
⋅
*
L
n
R
=
1 [
2
−
−
. 0
29
2
⋅
⋅
5 .
L
15
P,
+
. 0
(
V
f
_
D
12
sw
52
*
3850
44
* 1
O
MAX
the ratio of inductor peak current over average current in each phase,
*
=
10
−
⋅
)
10
5 .
2
10
*
0
=
m
=
n
−
5 .
10
⋅
*
*
∗
3
D
)
−
−
10
. 0
10
0
+
6
/
⋅
1 (
3
−
⋅
(
1 .
10
* 1
6
1 *
1 (
(
m
∗
−
−
3
18
+
6
6
. 1
*
55
2 .
n
−
−
10
4 .
+
∗
52
6
K
10
*
D
(
1
*
082
10
OCSET
T
−
=
=
5 .
*
10
−
)
P
6
L
−
10
18
)
. 2
_
*
*
−
D
6
−
9
MAX
+
10
15
67
4 (
)
*
nF
)
+



−
2
V
0 .
6
. 0
−
mS
=
0
CS
6
=
−
3 .
−
12



10
T
_
12
1
ROOM
TOFST
*
) 3 .
Ω
⋅
=
10
VDAC
. 0
(
=
135
0
108
)]
−
]
2 .
. 5
3
∗
=
)
14
3 /
ms
⋅
* 1
G
∗
and Resistor R
1 (
)
mS
CS
⋅
34
−
10
. 0
. 0
−
47
/
3
108
/(
I
∗
u
OCSET
11
1 [
⋅
)
250
+
⋅
9 .
3
3850
⋅
*
k
(
. 0
10
⋅
2
108
*
⋅
VDAC
10
−
. 0
6
108
−
−
)
6
0
3
=
∗
)
⋅
(
CS
⋅
181
100
1 (
(
0
−
.
3
+
. 0
−
k
1
108
Ω
25
−
)]
. 0
)
108
=
. 1
29
)



m
=
Ω
. 0
OCSET
082
May 18, 2009
) is 11.9uA with
IR3500