IR3624MTRPBF International Rectifier, IR3624MTRPBF Datasheet - Page 15

• Manufacturer Part Number: IR3624MTRPBF
• Description: IC CTRLR PWM SYNC BUCK 10-MLPD
• Manufacturer: International Rectifier

Specifications of IR3624MTRPBF

• Package / Case: 10-MLPD
• Voltage - Supply: 4.5 V ~ 14 V
• Frequency-max: 660kHz
• Operating Temperature: -40°C ~ 125°C
• Number Of Outputs: 1
• Duty Cycle: 71%
• Pwm Type: Voltage Mode
• Buck: Yes
• Boost: No
• Flyback: No
• Inverting: No
• Doubler: No
• Divider: No
• Cuk: No
• Isolated: No
• Frequency: 600kHz
• Supply Voltage Range: 4.5V To 14V
• Digital Ic Case Style: MLPD
• No. Of Pins: 10
• Operating Temperature Range: -40°C To +125°C
• Termination Type: SMD
• Input Voltage Primary Min: 5V
• Rohs Compliant: Yes
• Filter Terminals: SMD
• Control Mode: Voltage
• Controller Type: PWM
• Package: 10-Lead MLPD
• Circuit: Sync PWM Controller
• Vcc (min): 4.0
• Vcc (max): 14
• Vout (min): 0.6
• Vout (max): Vcc * 0.71
• Iout (a): 10
• Switch Freq (khz): Internal 600kHz
• Pbf: PbF Option Available
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: IR3624MPBFTR

To cancel one of the LC filter poles, place the
zero before the LC filter resonant frequency pole:
Using equations (15) and (16) to calculate C9.
One more capacitor is sometimes added in
parallel with C4 and R3. This introduces one
more pole which is mainly used to suppress the
switching noise.
The additional pole is given by:
The pole sets to one half of switching frequency
which results in the capacitor C
For a general solution for unconditionally stability
for any type of output capacitors, in a wide range
of ESR values we should implement local
feedback with a compensation network (typeIII).
The typically used compensation network for
voltage-mode controller is shown in figure 15.
In such configuration, the transfer function is
given by:
The error amplifier gain is independent of the
transconductance under the following condition:
By replacing Z
transformer function can be expressed as:
H
g
(
s
m
)
*
=
Z
sR
f
C
For
F
F
>>
8
z
z
POLE
(
C
=
=
1
4
F
75
1
0
F
P
=
+
.
in
P
75
%
and
<<
C
π
V
V
=
and Z
F
3
*
e
o
2
*
LC
)
F
2
π
2
R
*
=
s
π
3
*
⎡
⎢
⎣
1
(
1
g
R
*
1
f
1
1
L
according to figure 15, the
+
1
F
m
3
+
+
o
−
s
*
sR
*
*
sR
1
g
−
C
g
C
C
Z
m
3
4
4
C
o
m
3
1
in
⎛
⎜ ⎜
⎝
Z
+
C
*
Z
4
C
C
C
C
IN
>>
4
f
≅
4
-
* )
4
POLE
POLE
POLE
- -
+
*
π
1
[
C
1
C
(16)
*
3
+
3
:
R
⎞
⎟ ⎟
⎠
1
sC
⎤
⎥
⎦
3
-
( *
*
- -
7
F
(
1
R
s
(17)
+
8
sR
+
R
10
10
C
)
7
]
)
H(s) dB
As known, transconductance amplifier has high
impedance (current source) output, therefore,
consider should be taken when loading the error
amplifier output. It may exceed its source/sink
output current capability, so that the amplifier will
not be able to swing its output voltage over the
necessary range.
The compensation network has three poles and
two zeros and they are expressed as follows:
Cross over frequency is expressed as:
F
F
F
F
F
Fig.15: Compensation network with local
Z
P
P
P
1 z
z
2
1
2
3
IN
Gain(dB)
=
=
=
=
=
F
R
feedback and its asymptotic gain plot
0
2
2
2
2
o
C
10
π
π
π
π
=
7
*
*
F
R
*
*
R
V
C
Z
1
R
R
3
1
1
OUT
3
7
*
10
3
⎛
⎜ ⎜
⎝
*
( *
C
R
1
R
1
*
C
C
C
7
8
9
C
R
4
*
4
4
7
8
V
+
*
V
+
osc
V
C
in
C
Fb
REF
F
R
3
3
*
Z
10
⎞
⎟ ⎟
⎠
2
2
)
π
≅
≅
IR3624MPBF
*
2
R
1
L
2
π
3
F
o
E/A
π
P
*
*
2
C
*
R
1
C
o
1
C
3
7
*
3
*
C
R
F
3
C
8
P
Comp
3
4
Frequency
Z
Ve
f
15