LT3580
APPLICATIONS INFORMATION
V
–(V + ⏐V ⏐)
IN OUT
CESAT
C2
L1
L2
SW
SWX
V
–V
OUT
IN
D1
Q1
+
C1
C3
R
LOAD
+
3580 F12
Figure 12. Switch-On Phase of an Inverting Converter. L1 and L2 Have Positive dI/dt.
V
IN
+ ⏐V ⏐+ V
V
D
OUT
D
C2
L1
L2
SW
SWX
V
–V
OUT
IN
D1
Q1
+
C1
C3
R
LOAD
+
3580 F13
Figure 13. Switch-Off Phase of an Inverting Converter. L1 and L2 Currents Have Negative dI/dt.
L1
4.2μH
D1
V
OUT
V
5V
IN
12V
550mA
C2
10μF
V
SW
GND
IN
SHDN
130k
LT3580
RT
FB
VC
SYNC
SS
10k
1nF
C1
2.2μF
75k
0.1μF
3580 F14
C1: 2.2μF, 25V, X5R, 1206
C2: 10μF, 25V, X5R, 1206
D1: MICROSEMI UPS120
L1: SUMIDA CDR6D23MN-4R2
Figure 14. 1.2MHz, 5V to 12V Boost Converter
3580fc
19