LTC3855 LINER [Linear Technology], LTC3855 Datasheet - Page 39

• Manufacturer Part Number: LTC3855
• Description: Dual, Fast, Accurate Step-Down DC/DC Controller
• Manufacturer: LINER [Linear Technology]

APPLICATIONS INFORMATION
V
OUT1
1.2V
15A
4.5V TO 26V
V
C
100μF
IN
OUT1
2
+
+
100
90
80
60
40
70
50
0.1
C
330μF
C
220μF
OUT2
2
IN1
EFFICIENCY
FORCED CONTINUOUS MODE
DISCONTINUOUS MODE
Figure 13. Design Example: 4.5V to 26V Input, 1.2V/15A and 1.5V/15A Dual Outputs,
350kHz, DCR Sense, DTR Enabled, Step-Down Converter
0.56μH
LOAD CURRENT (A)
C
10μF
L1
IN2
3
3.57k
1
MT1
MB1
POWER
V
V
LOSS
IN
OUT
= 12V
= 1.2V
10
3838 F13b
2.2Ω
2.2Ω
15k
0.1μF
90.9k
82.5k
100k
3.0
2.5
2.0
1.5
1.0
0.5
0
1μF
10k
22pF
DB1
1μF
0.1μF
115k
220pF
PGOOD1
0.01μF
10k
4.7μF
V
SENSE1
SENSE1
BOOST1
TG1
SW1
DRV
INTV
BG1
PGND
V
V
PGOOD1
TRACK/SS1
ITH1
DTR1
V
RT
SGND
RUN1
IN
OUTSENSE1
OUTSENSE1
RNG1
CC1
CC
–
+
LTC3838
MODE/PLLIN
+
–
TRACK/SS2
SENSE2
PHASMD
SENSE2
PGOOD2
BOOST2
CLKOUT
DRV
EXTV
V
RUN2
DTR2
RNG2
SW2
ITH2
V
TG2
BG2
CC2
FB2
CC
–
+
PGOOD2
0.01μF
220pF
100
80
40
90
70
60
50
0.1μF
22pF
100k
0.1
90.9k
82.5k
0.1μF
DB2
15k
EFFICIENCY
10k
FORCED CONTINUOUS MODE
DISCONTINUOUS MODE
15k
LOAD CURRENT (A)
MT2
MB2
3838 F13a
1
C
C
C
C
DB1, DB2: CENTRAL SEMI CMDSH-4ETR
L1, L2: VISHAY IHLP4040DZERR56M01
MT1, MT2: RENESAS RJK0305DPB
MB1, MB2: RENESAS RJK0330DPB
IN1
IN2
OUT2
OUT1
3.57k
POWER
0.56μH
: PANASONIC EEEFK1V221P
: TAIYO YUDEN GMK325BJ106MN-T
LOSS
, C
, C
L2
V
V
IN
OUT
OUT4
OUT3
= 12V
= 1.5V
: SANYO 2R5TPE330M9
: MURATA GRM31CR60J107ME39L
3838 F13c
10
C
330μF
LTC3838
OUT4
3.0
2.0
0
2.5
1.5
1.0
0.5
2
+
C
100μF
OUT3
2
39
3838fa
V
1.5V
15A
OUT2