LTC3864 Datasheet, PDF (25/28 Pages) Linear Technology – 60V Low IQ Step-Down DC/DC Controller with 100% Duty Cycle Capability

TYPICAL APPLICATIONS
LTC3864
24V to 60V Input, 24V/1A Output at 750kHz
C_CAP
0.1µF
CAP
C_IN2 ⁺
2.2µF
V_IN
C_IN1 ^{24V TO 60V}
33µF
63V
C_ITH1
6.8nF _{RITH 30.1k}
C_ITH2 100pF
RUN
MODE/PLLN
V_IN
SENSE
SS
GATE
ITH LTC3864
R_FREQ 97.6k
FREQ
PGOOD
C_VIN
0.1µF
R_SENSE
50mΩ
MP L1
47µH
D1
R_PGD2
768k
R_FB2
887k
10µF
V_OUT*
24V
1A
SGND
V_FB
PGND
R_PGD1
200k
R_FB1
30.1k
C_IN1: NICHICON UPJ1J100MPD
D1: DIODES INC SBR3U100LP
L1: TOKO 1217AS-H-470M
MP: VISHAY/SILICONIX SI7113DN
*V_OUT FOLLOWS V_IN WHEN 3.5V ≤ V_IN ≤ 24V
3864 TA02a
Efficiency
100
90
80
Burst Mode
OPERATION
70
60
PULSE-SKIPPING
50
40
30
0.01
V_IN = 48V
V_OUT = 24V
0.1
1
LOAD CURRENT (A)
3864 TA02b
C_SS
0.1µF
C_ITH1
10nF
R_ITH 14k
C_ITH2 100pF
C_CAP
0.1µF
CAP
RUN
V_IN
MODE/PLLN
SENSE
SS
GATE
LTC3864
ITH
R_FREQ 24.3k
FREQ
SGND
PGOOD
V_FB
PGND
C_IN1: SANYO 63ME33AX
D1: VISHAY V10P10
L1: WÜRTH 7447709100
MP: VISHAY/SILICONIX SI7461DP
3.5V to 48V Input, 1.8V/4A Output at 100kHz
C_VIN
0.1µF
C_IN2 ⁺
10µF
×2
V_IN
C_IN1 ^{3.5V TO 48V}
33µF
63V
R_SENSE
15mΩ
MP L1
10µH
D1
R_PGD
100k
R_FB2
102k
100µF
×2
+
V_OUT
1.8V
4A
330µF
6.3V
80
70
60
50
40
30
0.01
R_FB1
80.6k
3864 TA03a
Efficiency
Burst Mode
OPERATION
PULSE-SKIPPING
V_IN = 12V
V_OUT = 1.8V
0.1
1
LOAD CURRENT (A)
3864 TA03b
3864f
25