
Application Note 1521
Typical Performance Curves
95
90
85
80
V IN = 12V
95
90
85
80
V IN = 12V
75
70
V IN = 18V
V IN = 24V
75
70
V IN = 18V
V IN = 24V
65
65
60
55
50
45
40
0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7 3.0
60
55
50
45
40 0.3
0.6
0.9
1.2
1.5
1.8
2.1
2.4
2.7
3.0
OUTPUT CURRENT (A)
FIGURE 3. EFFICIENCY FOR V OUT1 (V OUT2 IS
DISABLED)
3.310
3.305
OUTPUT CURRENT (A)
FIGURE 4. EFFICIENCY FOR V OUT2 (V OUT1 IS
DISABLED)
2.505
2.500
3.300
2.495
V IN = 12V
3.295
V IN = 12V
V IN = 18V
V IN = 24V
2.490
V IN = 18V
V IN = 24V
3.290
0.0 0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7 3.0
OUTPUT CURRENT (A)
2.485
0.0 0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7 3.0
OUTPUT CURRENT (A)
FIGURE 5. V OUT1 (3.3V) REGULATION
V OUT1
FIGURE 6. V OUT2 (2.5V) REGULATION
V OUT1
V OUT2
V OUT2
PGOOD
FIGURE 7. OUTPUT RIPPLEs AT FULL LOAD (20BW);
INPUT VOLTAGE = 12V
2
FIGURE 8. SOFT-START WAVEFORMS
AN1521.0
January 15, 2010