IR3521MTRPBF International Rectifier, IR3521MTRPBF Datasheet - Page 30

• Manufacturer Part Number: IR3521MTRPBF
• Description: IC CTRL XPHASE3 SVID 32-MLPQ
• Manufacturer: International Rectifier
• Series: XPhase3™r

Specifications of IR3521MTRPBF

• Applications: Processor
• Current - Supply: 10mA
• Voltage - Supply: 4.75 V ~ 7.5 V
• Operating Temperature: 0°C ~ 100°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

Adaptive voltage positioning lowers the converter voltage by R
the converter. Pre-select feedback resistor R
Calculate the desired effective feedback resistor at the maximum temperature R
A negative temperature constant (NTC) thermistor R
for the inductor DCR thermal compensation. Pre-select the value of R
room temperature but also bigger than R
thermistor resistance at maximum allowed temperature, T
Select the series resistor R
has non-linear characteristics in the operational temperature range.
Use equation (17) to determine RFB11.
R
FB
13

(
R
THERM
1

R
TMAX
R
1
)
TMAX
2
FB13

R
R
4
R
FB
R
1
1
DRP
( *
FB
FB

11
by using equation (16). R
R
_
11
R
THERM
_
R

M
THERM


R

V
1
FB
R
*
1
O
FB
R
G
R
_
_
1
DRP
CS
I
TMAX
R
FB_M
NLOFST
_
*
FB
R
EXP


11
1

1
FB,
R
R


R
n
L
FB
at the maximum allowed temperature. R
(
L
R
[

_
R
and calculate the droop resistor RDRP,
B
13
_
O
MAX
THERM
R
ROOM
THERM
*
O

n
1
R
THERM1
Page 30
1
THERM

*
1
R
G
( *
TMAX
MAX.
CS
2
T
FB13
1
L
1
* )
is required to sense the temperature of the power stage
_
1
MAX
R
R
is incorporated to linearize the NTC thermistor which
FB
O
TMAX1
*I
_

R
O,
*
T
R
_
where R
FB
ROOM
THERM.
1
is calculated from (15).
_
M
/(
)]
R
FB
O
R
_
FB_M
THERM
R
is the required output impedance of
(17)

(14)
R
(12)
(13)
FB
using (14)
_
M
must be bigger than R
TMAX1
))
(15)

(
R
THERM
is defined as the NTC
1

IR3521
V3.03
R
TMAX
1
)
(16)
FB_R
at