Datasheet

LTC3863
33
3863f
For more information www.linear.com/3863
Figure 15. 4.5V to 16V Input, –5V/1.7A, –12V/1A Output, 350kHz Inverting Converter
TYPICAL APPLICATIONS
350kHz
16mΩ
L1
10µH
Q1
D1
CAP
0.47µF
PGND
LTC3863
3863 F15a
SS
ITH
FREQ
SGND
RUN
V
IN
PLLIN/MODE
SENSE
GATE
V
FBN
V
FB
14.7k
61.9k
R
FBO
698k
V
OUT
–5V 1.7A (SHORT R
FBO
)
–12V 1A
80.6k
C
IN1
: PANASONIC 20SVP100M
C
IN2
: TDK C3225X7R1E106M
C
OUT1
: TDK C4532X7R1C336M
C
OUT3
: PANASONIC 16TQC150MYF
D1: DIODES B540C
L1: TOKO 919AS-100M
Q1: VISHAY SI7129DN-T1-GE3
V
IN
4.5V TO 16V
C
IN1
100µF
20V
C
OUT1
33µF
16V
×2
C
IN2
10µF
25V
×2
C
OUT3
150µF
16V
×2
27nF
0.1µF
390pF
68pF
511k
+
+
5V Efficiency –12V Efficiency
LOAD CURRENT (A)
0.002
40
EFFICIENCY (%)
POWER LOSS (W)
60
90
80
0.02 0.2 2
3863 F15b
20
30
50
70
10
0
4
6
9
8
2
3
5
7
1
0
EFFICIENCY
POWER LOSS
V
IN
= 12V
V
OUT
= –5V
PULSE-SKIPPING MODE
Burst Mode OPERATION
LOAD CURRENT (A)
0.002
40
EFFICIENCY (%)
POWER LOSS (W)
60
90
80
0.02 0.2 2
3863 F15b
20
30
50
70
10
0
4
6
9
8
2
3
5
7
1
0
EFFICIENCY
POWER LOSS
V
IN
= 12V
V
OUT
= –12V
PULSE-SKIPPING MODE
Burst Mode OPERATION