LTC3864 Datasheet, PDF (28/28 Pages) Linear Technology – 60V Low IQ Step-Down DC/DC Controller with 100% Duty Cycle Capability

LTC3864
TYPICAL APPLICATION
3.5V to 38V Input, 3.3V/3A Output at 300kHz
C_SS
0.1µF
C_ITH1
10nF _{RITH 20k}
C_ITH2 100pF
C_CAP
0.1µF
CAP
RUN
V_IN
MODE/PLLN
SS
SENSE
GATE
ITH LTC3864
R_FREQ 42.2k
FREQ
SGND
PGOOD
V_FB
PGND
C_IN1: SANYO 63ME33AX
D1: VISHAY V15P45S
L1: WÜRTH 7447709100
MP: VISHAY/SILICONIX Si7611DN
C_IN2 ⁺
10µF
×2
V_IN
C_IN1 ^{3.5V TO 60V}
33µF
63V
C_VIN
0.1µF
R_SENSE
20mΩ
MP L1
6.8µH
47µF
×2
V_OUT
3.3V
3A
D1
R_PGD
100k
R_FB2
634k
R_FB1
200k
3864 TA05a
Efficiency
90
Burst Mode
OPERATION
80
70
60
50
40
0.01
PULSE-SKIPPING
V_IN = 12V
V_OUT = 3.3V
0.1
1
LOAD CURRENT (A)
3864 TA05b
RELATED PARTS
PART NUMBER
LTC3891
LTC3890
LTC3824
LT3845A
LTC3834/LTC3834-1
LTC3835/LTC3835-1
LTC3857/LTC3857-1
LTC3858/LTC3858-1
LTC3859A
DESCRIPTION
60V, Low I_Q, Synchronous Step-Down DC/DC
Controller
60V, Low I_Q, Dual 2-Phase Synchronous
Step-Down DC/DC Controller
60V, Low I_Q, Step-Down DC/DC Controller, 100%
Duty Cycle
60V, Low I_Q, Single Output Step-Down DC/DC
Controller
Low I_Q, Single Output 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, Triple Output Buck/Buck/Boost
Synchronous DC/DC Controller
COMMENTS
Phase-Lockable Fixed Frequency 50kHz to 900kHz 4V ≤ V_IN ≤ 60V,
0.8V ≤ V_OUT ≤ 24V, I_Q = 50µA
Phase-Lockable Fixed Frequency 50kHz to 900kHz 4V ≤ V_IN ≤ 60V,
0.8V ≤ V_OUT ≤ 24V, I_Q = 50µA
Selectable Fixed Frequency 200kHz to 600kHz 4V≤ V_IN ≤ 60V,
0.8V ≤ V_OUT ≤ V_IN, I_Q = 40µA, MSOP-10E
Synchronizable Fixed Frequency 100kHz to 600kHz 4V ≤ V_IN ≤ 60V,
1.23V ≤ V_OUT ≤ 36V, I_Q = 120µA, TSSOP-16
Phase-Lockable Fixed Frequency 140kHz to 650kHz, 4V ≤ V_IN ≤ 36V,
0.8V ≤ V_OUT ≤ 10V, I_Q = 30µA/80µA
Phase-Lockable Fixed Frequency 50kHz to 900kHz, 4V ≤ V_IN ≤ 38V,
0.8V ≤ V_OUT ≤ 24V, I_Q = 50µA/170µA
All Outputs Remain in Regulation Through Cold Crank 2.5V ≤ V_IN ≤ 38V,
V_OUT(BUCKS) Up to 24V, V_OUT(BOOST) Up to 60V, I_Q = 55µA
28 Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ^● FAX: [phone] ^● www.linear.com
3864f
LT 1012 • PRINTED IN USA
 LINEAR TECHNOLOGY CORPORATION 2012