LTC3838-2_15 Datasheet, PDF (41/56 Pages) Linear Technology – Dual, Fast, Accurate Step-Down DC/DC Controller with xternal Reference Voltage and Dual Differential Output Sensing

LTC3838-2
APPLICATIONS INFORMATION
V_IN
4.5V TO 26V
+ _CIN1
220µF
C_IN2
10µF
×3
3.57k
V_OUT1
1.2V
15A
L1
MT1
0.56µH
+ C_OUT1
C_OUT2
100µF
330µF
×2
×2
MB1
2.2Ω
1µF
15k
0.1µF
0.1µF
LTC3838-2
V_IN
SENSE1^–
SENSE2^–
SENSE1⁺
SENSE2⁺
0.1µF 15k
0.1µF
BOOST1
TG1
DB1
2.2Ω
1µF
SW1
4.7µF
DRV_CC1
INTV_CC
BG1
BOOST2
TG2
SW2
DRV_CC2
EXTV_CC
BG2
PGND
EXTV_REF2
10k
V_OUTSENSE1+ V_DFB2+
10k
MT2
DB2
MB2
V_REF2+
0.4V TO 1.25V _20k
10k
20k
V_REF2–
3.57k
L2
0.56µH
C_OUT4 +
330µF
×2
C_OUT3
100µF
×2
V_OUT2
0.8V TO 2.5V
15A
100k
V_{OUTSENSE1–}
PGOOD1 _PGOOD1
0.01µF
V_DFB2–
PGOOD2 ^PGOOD2
0.01µF
100k
TRACK/SS1 TRACK/SS2
22pF
22pF
ITH1
220pF
90.9k
ITH2
220pF
90.9k
82.5k
115k
DTR1
RT
SGND
RUN1
DTR2
PHASMD
MODE/PLLIN
CLKOUT
RUN2
82.5k
38382 F13a
C_IN1: PANASONIC EEEFK1V221P
C_IN2: TAIYO YUDEN GMK325BJ106MN-T
C_OUT2, C_OUT4: SANYO 2R5TPE330M9
C_OUT1, C_OUT3: MURATA GRM31CR60J107ME39L
DB1, DB2: CENTRAL SEMI CMDSH-4ETR
L1, L2: VISHAY IHLP4040DZERR56M01
MT1, MT2: RENESAS RJK0305DPB
MB1, MB2: RENESAS RJK0330DPB
100
3.0
FORCED CONTINUOUS MODE
DISCONTINUOUS MODE
90
2.5
80
EFFICIENCY
70
60
2.0
1.5
POWER
LOSS
1.0
50
40
0.1
0.5
V_IN = 12V
V_OUT = 1.2V
0
1
10
LOAD CURRENT (A)
38382 F13b
100
3.0
FORCED CONTINUOUS MODE
DISCONTINUOUS MODE
90
2.5
80
EFFICIENCY
70
60
2.0
1.5
POWER
LOSS
1.0
50
40
0.1
0.5
V_IN = 12V
V_OUT = 1.5V
0
1
10
LOAD CURRENT (A)
38382 F13c
Figure 13. Design Example: 4.5V to 26V Input, 1.2V/15A and 0.8V to 2.5V/15A
(V_OUT2: EXTV_REF2 = 2:1) Dual Outputs, 350kHz, DCR Sense, DTR Enabled, Step-Down Converter
For more information www.linear.com/3838-2
38382f
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