IR3513ZMTRPBF International Rectifier, IR3513ZMTRPBF Datasheet - Page 28

• Manufacturer Part Number: IR3513ZMTRPBF
• Description: IC CTRL XPHASE3 POL 32-MLPQ
• Manufacturer: International Rectifier
• Series: XPhase3™r

Specifications of IR3513ZMTRPBF

• Applications: Processor
• Current - Supply: 3mA
• Voltage - Supply: 8 V ~ 16 V
• Operating Temperature: 0°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: *
• Package: 32-Lead MLPQ
• Circuit: X-Phase Control IC
• Switch Freq (khz): 250kHz to 1.5MHz
• Pbf: PbF Option Available
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

VCCL Programming Resistor R
Since VCCL voltage is proportional to the MOSFET gate driver loss and inversely proportional to the
MOSFET conduction loss, the optimum voltage should be chosen to maximize the converter efficiency. VCCL
linear regulator consists of an external NPN transistor, a ceramic capacitor and a programmable resistor
divider. Pre-select R
VCCL Capacitor C
The capacitor is selected based on the stability requirement of the linear regulator and the load current to be
driven. The linear regulator supplies the bias and gate drive current of the phase ICs. A 4.7uF normally ensures
stable VCCL performance for most applications.
VCCL Regulator Drive Resistor R
minimum input voltage requirements. The following equation gives an estimate of the average load current of
the switching phase ICs.
Q
I
a maximum VCCL, the maximum R
given by
Due to limited pull down capability of the VCCLDRV pin, make sure the following condition is satisfied.
In the above equation, V
above condition is not satisfied there is a need to use a device with higher β
be used instead of a single NPN transistor.
Inductor Current Sensing Capacitor C
The DC resistance of the inductor is utilized to sense the inductor current. Usually the resistor R
C
across the capacitor C
component of the capacitor voltage is different from that of the real inductor current. The time constant mismatch
does not affect the average current sharing among the multiple phases, but affects the current signal ISHARE.
Measure the inductance L and the inductor DC resistance R
follows.
The drive resistor is primarily dependent on the load current requirement of the linear regulator and the
VCCL_C
gb
CS
and Q
in parallel with the inductor are chosen to match the time constant of the inductor, and therefore the voltage
is the VCCL current of the controller and n is the number of phases. For a minimum input voltage and
Page 28
gt
are the gate charge of the top and bottom FET, I
VCCL
VCCLFB1
CS
I
R
I
( min) and V
drive
CS
R
represents the inductor current. If the two time constants are not the same, the AC
VCCLFB
R
, and calculate R
=
_
VCCLDRV
avg
V
L
C
I
(max)
CS
VCCLFB1
=
R
2
L
=
(
VCCLDRV
VCCLDRV
Q
REPLACEMENT PRODUCT – IR3513ZMTRPBF
=
R
VCCL
gb
−
NOT RECOMMENDED FOR NEW DESIGNS
VCCLFB
V
I
R
( max) is the minimum and maximum anticipated input voltage. If the
0
I
VCCLDRV
+
CS
7 .
(min)
and R
Q
−
required to use the full pull-down current of the VCCL driver is
and Resistor R
−
VCCL
1
gt
I
*
VCCLFB2
. 1
)
drive
. 1
−
19
⋅
19
n
0
VCCLFB2
_
7 .
(min)
+
avg
−
I
VCCL
/
VCCL
β
from (11).
<
min
10
_
PHS
mA
(max)
CS
VCCL_PHS
L
⋅
. Pre-select the capacitor C
(
n
−
) 1
is the VCCL current of the phase IC-s,
+
I
VCCL
(14)
min
_
C
(13)
or Darlington configuration can
CS
(15)
(11)
May 11, 2008
and calculate R
(12)
CS
IR3513
and capacitor
CS
as