LTC3863_15 Datasheet, PDF (31/38 Pages) Linear Technology – 60V Low IQ Inverting DC/DC Controller

Typical Applications
750kHz
50pF
0.1µF
4.7nF
36.5k
100k
0.47µF
RUN ^CAP
V_IN
PLLIN/MODE
SS
SENSE
GATE
LTC3863
ITH
FREQ
SGND
V_FBN
PGND ^VFB
LTC3863
C_IN1 +
100µF
50V
25mΩ
V_IN
C_IN2 ^{5V TO 23V}
10µF
25V
×2
Q1 ^D1
L1
15µH 191k
C_OUT1
10µF
25V
×2
C_OUT3
100µF
20V
V_OUT
–18V
700mA
47pF
3863 F12a
8.45k
C_IN1: NICHICON UCJ1H101MCL1GS
C_IN2: TDK C3225X7R1E108M
C_OUT1: MURATA GRM32DR61E106KA12L
C_OUT3: PANASONIC 20SVO100M
D1: DIODES SBR8U60P5
L1: WURTH 744770115
Q1: VISHAY SI7469DP
90
80
70
60
50
40
30
20
10
0
0.001
Efficiency
PULSE-SKIPPING MODE
Burst Mode OPERATION
V_IN = 12V
V_OUT = –18V
EFFICIENCY
POWER LOSS
0.01
0.1
LOAD CURRENT (A)
9
8
7
6
5
4
3
2
1
0
1
3863 F12b
60
50
40
30
20
10
0
–10
–20
–30
1
Gain/Phase
90
V_IN = 12V
V_OUT = –18V 75
60
PHASE
45
30
15
GAIN
0
–15
–30
10
FREQUENCY (kHz)
–45
100
3863 F12c
Figure 12. 5V to 23V Input, –18V/700mA Output, 750kHz Inverting Converter
Gain/Phase Measurements Taken with OMICRON Lab Bode 100 Vector Network Analyzer.
For more information www.linear.com/3863
3863fa
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