LTM4641
(Figure 45 circuit with R
fSET
per Table 1 and R
SET1A
, R
SET1B
and R
SET2
per Table 2, unless otherwise noted)
Efficiency vs Load Current at 36V
IN
95
90
85
EFFICIENCY (%)
EFFICIENCY (%)
80
75
70
65
60
0
6.0V
OUT
5.0V
OUT
3.3V
OUT
2.5V
OUT
1.8V
OUT
1
2
1.5V
OUT
1.2V
OUT
1.0V
OUT
0.9V
OUT
9
10
95
90
85
80
75
70
65
60
0
6.0V
OUT
5.0V
OUT
3.3V
OUT
2.5V
OUT
1.8V
OUT
1
2
1.5V
OUT
1.2V
OUT
1.0V
OUT
0.9V
OUT
9
10
EFFICIENCY (%)
TYPICAL PERFORMANCE CHARACTERISTICS
Efficiency vs Load Current at 24V
IN
95
90
85
80
75
70
65
60
Efficiency vs Load Current at 12V
IN
6.0V
OUT
5.0V
OUT
3.3V
OUT
2.5V
OUT
1.8V
OUT
0
1
2
1.5V
OUT
1.2V
OUT
1.0V
OUT
0.9V
OUT
9
10
3
7 8
4 5 6
OUTPUT CURRENT (A)
3
7 8
4 5 6
OUTPUT CURRENT (A)
3
7 8
4 5 6
OUTPUT CURRENT (A)
4641 G01
4641 G02
4641 G03
Efficiency vs Load Current at 6V
IN
95
90
85
EFFICIENCY (%)
80
75
70
65
60
0
3.3V
OUT
2.5V
OUT
1.8V
OUT
1.5V
OUT
1
2
1.2V
OUT
1.0V
OUT
0.9V
OUT
9
10
90
80
70
EFFICIENCY (%)
60
50
40
30
20
10
Pulse-Skipping vs Forced
Continuous Mode Efficiency,
28V
IN
to 3.3V
OUT
V
OUT
50mV/DIV
AC-COUPLED
I
OUT
2.5A/DIV
FCB = SGND
FORCED
CONTINUOUS
1V Transient Response, 38V
IN
FCB = INTV
CC
(PULSE-SKIPPING)
20µs/DIV
0A TO 5A LOAD STEPS AT 5A/µs
FRONT PAGE CIRCUIT WITH
OV
PGM
= OPEN CIRCUIT
10
4641 G06
3
7 8
4 5 6
OUTPUT CURRENT (A)
0
0.001
0.1
0.01
1
OUTPUT CURRENT (A)
4641 G04
4641 G05
1V Transient Response, 4.5V
IN
V
OUT
50mV/DIV
AC-COUPLED
I
OUT
2.5A/DIV
V
OUT
50mV/DIV
AC-COUPLED
I
OUT
2.5A/DIV
3.3V Transient Response,
28V
IN
to 3.3V
OUT
V
OUT
1V/DIV
Output Start-Up, No Load
I
IN
200mA/DIV
RUN
5V/DIV
20µs/DIV
0A TO 5A LOAD STEPS AT 5A/µs
FIGURE 46 CIRCUIT
4641 G08
20µs/DIV
0A TO 5A LOAD STEPS AT 5A/µs
FRONT PAGE CIRCUIT WITH
OV
PGM
= OPEN CIRCUIT
4641 G07
V
IN
= 24V
C
IN(MLCC)
= 2
×
10µF X7R
800µs/DIV
4641 G09
4641f
8
LINER [ LINEAR TECHNOLOGY ]
