LTC3838-1_15 Datasheet, PDF (38/52 Pages) Linear Technology – Dual, Fast, Accurate Step-Down DC/DC Controller with Dual Differential Output Sensing

LTC3838-1
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
LTC3838-1
V_IN
SENSE1^–
SENSE2^–
SENSE1⁺
SENSE2⁺
BOOST1
TG1
DB1
2.2Ω
1µF
SW1
4.7µF
DRV_CC1
INTV_CC
BG1
BOOST2
TG2
SW2
DRV_CC2
EXTV_CC
BG2
0.1µF 15k
0.1µF
DB2
3.57k
MT2
L2
0.56µH
V_OUT2
1.5V
15A
C_OUT4 +
330µF
C_OUT3
100µF
MB2
×2
×2
PGND
10k
V_OUTSENSE1+ V_DFB2+
10k
10k
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
V_RNG
RT
SGND
RUN1
DTR2
PHASMD
MODE/PLLIN
CLKOUT
RUN2
82.5k
15k
10k //15k
SGND
38381 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
100
3.0
FORCED CONTINUOUS MODE
DISCONTINUOUS MODE
90
2.5
80
EFFICIENCY
70
60
2.0
1.5
POWER
LOSS
1.0
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)
38381 F13b
50
40
0.1
0.5
V_IN = 12V
V_OUT = 1.5V
0
1
10
LOAD CURRENT (A)
38381 F13c
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
38
For more information www.linear.com/3838-1
38381f