LTC3890-2 Datasheet, PDF (40/40 Pages) Linear Technology – 60V Low IQ, Dual, 2-Phase Synchronous Step-Down DC/DC Controller

LTC3890-2
TYPICAL APPLICATION
High Efficiency Dual 12V/3.3V Step-Down Converter
R_A1
6.98k
R_B1
100k
C_ITH1A 100pF
SENSE1⁺
C1
1nF
SENSE1^–
V_FB1
PGOOD1
PGOOD2
BG1
C_ITH1 470pF
R_ITH1
34.8k
C_SS1 0.01μF
SW1
ITH1
BOOST1
LTC3890-2
TRACK/SS1
TG1
R_FREQ
41.2k
C_SS2 0.01μF
V_OUT1
C_ITH2 1000pF
R_ITH2
34.8k
C_ITH2A
100pF
I_LIM
PHASMD
CLKOUT
PLLIN/MODE
SGND
EXTV_CC
RUN1
RUN2
FREQ
V_IN
INTV_CC
PGND
TG2
TRACK/SS2 BOOST2
SW2
ITH2
BG2
INTV_CC
100k
100k
C_B1
0.47μF
D1
C_INT
4.7μF
D2
C_B2 0.47μF
MBOT1 _RSENSE1
9mΩ
L1
8μH
C_OUT1
180μF
V_OUT1
12V
3A
MTOP1
+ _CIN
100μF
V_IN
12.5V TO 60V
2.2μF
x3
MTOP2
L2
4.7μH
R_SENSE2
10mΩ
MBOT2
V_OUT2
3.3V
5A
C_OUT2
470μF
R_A2
31.6k
R_B2
100k
V_FB2
SENSE2^–
C2
1nF
SENSE2⁺
MTOP1, MTOP2, MBOT1, MBOT2: RJK0651DPB
L1: COILCRAFT SER1360-802KL
L2: COILCRAFT SER1360-472KL
C_OUT1: 16SVP180MX
C_OUT2: SANYO 6TPE470M
D1, D2: DFLS1100
38902 TA08
RELATED PARTS
PART NUMBER
LTC3891
LTC3857/LTC3857-1/
LTC3858/LTC3858-1
LTC3834/LTC3834-1/
LTC3835/LTC3835-1
LTC3810
DESCRIPTION
60V, Low I_Q, Synchronous Step-Down DC/DC Controller
with 99% Duty Cycle
Low I_Q, Dual Output 2-Phase Synchronous Step-Down
DC/DC Controllers with 99% Duty Cycle
Low I_Q, Single Output Synchronous Step-Down
DC/DC Controllers with 99% Duty Cycle
100V Synchronous Step-Down DC/DC Controller
LTC3859A
Low I_Q, Triple Output Buck/Buck/Boost Synchronous
DC/DC Controller with Improved Burst Mode Operation
40 LinearTechnology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ^● FAX: [phone] ^● www.linear.com
COMMENTS
PLL Fixed Frequency 50kHz to 900kHz, 4V ≤ V_IN ≤ 60V,
0.8V ≤ V_OUT ≤ 24V, TSSOP-20E, 3mm × 4mm QFN-20
PLL Fixed Frequency 50kHz to 900kHz, 4V ≤ V_IN ≤ 38V,
0.8V ≤ V_OUT ≤ 24V, I_Q = 50μA/170μA
PLL Fixed Frequency 140kHz to 650kHz, 4V ≤ V_IN ≤ 36V,
0.8V ≤ V_OUT ≤ 10V, I_Q = 30μA/80μA
Constant On-Time Valley Current Mode, 4V ≤ V_IN ≤ 100V,
0.8V ≤ V_OUT ≤ 0.93V_IN, SSOP-28
Outputs (≥5V) Remain in Regulation Through Cold Crank,
2.5V ≤ V_IN ≤ 38V, V_OUT(BUCKS) Up to 24V, V_OUT(BOOST) Up to 60V
38902f
LT 1112 • PRINTED IN USA
© LINEAR TECHNOLOGY CORPORATION 2012