IR3084UMTRPBF International Rectifier, IR3084UMTRPBF Datasheet - Page 41

• Manufacturer Part Number: IR3084UMTRPBF
• Description: IC CTLR XPHASE 28-MLPQ
• Manufacturer: International Rectifier
• Series: XPhase™r

Specifications of IR3084UMTRPBF

• Package / Case: 28-MLPQ
• Mounting Type: Surface Mount
• Current - Supply: 14mA
• Voltage - Supply: 9.5 V ~ 16 V
• Operating Temperature: 0°C ~ 100°C
• Applications: Processor
• Package: 28-Lead MLPQ
• Circuit: X-Phase Control IC
• Switch Freq (khz): 150kHz to 1.0MHz
• Pbf: PbF Option Available
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Phase Delay Timing Resistors RPHASEx1 to RPHASEx2 (x=1,2,…,7)
The phase delay resistor ratios for phases 1 to 7 at 400kHz are (from the X−Phase Excel based design
spreadsheet); RAPHASE1=0.580, RAPHASE2=0.397, RAPHASE3=0.215, RAPHASE4=0.206,
RAPHASE5=0.353 RAPHASE6=0.5 and RAPHASE7=0.647.
Pre−select RPHASE11=RPHASE21=RPHASE31=RPHASE41=RPHASE51=RPHASE61=RPHASE71=20kΩ,
Calculating the other resistors from the same formula results in; R
R
Phase ICs 1−3 should have the RMPOUT voltage from the 3084 controller connected to their RMPIN− pin so
they will trigger on the negative slope of the RMPOUT waveform. Phase ICs 4−7 should have the RMPOUT
voltage from the 3084 controller connected to their RMPIN+ pin so they will trigger on the positive slope of the
RMPOUT waveform.
Bootstrap Capacitor C
Choose C
Decoupling Capacitors for Phase IC and Power Stage
Choose C
VOLTAGE LOOP COMPENSATION
AL−Polymer output capacitors are used in the design, for instructional purposes Type III compensation as shown
in Figure 18(b) will be demonstrated here. First, choose the desired crossover frequency as 1/10 of the switching
frequency, f
PHASE42
Choose C
C
C
R
R
CP
CP
FB
FB
Page 41 of 47
1
R
=
=
=
=5.2kΩ, P
=
BST
VCC
PHASE
2 (
10
C
4
=
1
2
π
π
=0.1uF.
=40 kHz, and determine Rcp and C
=0.1uF, C
CP1
. 2
*
*
12
*
*
49
R
R
f
f
=100pF to reduce high frequency noise.
=
FB
L
C
C
1
K
CP
PHASE52
E
1
)
*
Ω
=
2
−
*
RA
R
*
C
1
2
RA
VCCL
BST
FB
L
PHASE
E
*
E
1
PHASE
324
*
=10.9kΩ, R
=
=
=0.1uF
V
C
1
10
o
4
E
π
=
1
*
*
∗
162
*
R
R
40
FB
(
PHASE
220
Ω
*
*
PHASE62
1
10
V
11
*
PWMRMP
3
10
=
*
. 2
162
−
1
9
=20kΩ, R
49
−
. 0
/
Choose R
CP
=
) 7
. 0
58
*
=
2 (
using Equations (30) and (31):
58
10
( *
12
π
3
560
∗
3 .
*
PHASE72
20
nF
40
FB1
*
*
*
10
=162Ω
10
10
−
3
6
3
=36.6kΩ.
PHASE22
)
*
=
2
10
( *
27
. 1
)
30
220
6 .
=
Choose C
k
=13.2kΩ, R
−
Ω
53
*
. 0
10
nF
015
−
9
,
/
−
) 7
FB
130
PHASE32
=10nF
( *
560
*
Choose C
* 1
*
10
=5.48kΩ,
10
IR3084U
−
3
−
6
*
CP
9/14/2005
10
=56nF
* )
324
*
0
8 .