Datasheet

LTC3561
3
3561f
ELECTRICAL CHARACTERISTICS
Note 5: T
J
is calculated from the ambient T
A
and power dissipation P
D
according to the following formula:
LTC3561EDD: T
J
= T
A
+ (P
D
• 43°C/W)
Note 6: Switch on-resistance is guaranteed by correlation to wafer level
measurements.
Note 7: 4MHz operation is guaranteed by design but not production tested
and is subject to duty cycle limitations (see Applications Information).
TYPICAL PERFOR A CE CHARACTERISTICS
UW
Switching Waveforms
V
IN
= 3.3V 2µs/DIV 3561 G02.eps
V
OUT
= 2.5V
I
LOAD
= 50mA
CIRCUIT OF FIGURE 6
V
OUT
10mV/
DIV
I
L1
100mA/
DIV
2.5 3.5 4.5 5.53.0 4.0 5.0 6.0
V
IN
(V)
EFFICIENCY (%)
100
95
90
85
80
75
70
65
60
3561 G05
I
OUT
= 0.4A
I
OUT
= 1.0A
V
OUT
= 2.5V
CIRCUIT OF FIGURE 6
Efficiency vs V
IN
Load Step
V
IN
= 3.3V 40µs/DIV 3561 G06.eps
V
OUT
= 2.5V
I
LOAD
= 0.20A TO 1A
CIRCUIT OF FIGURE 6
V
OUT
100mV/
DIV
I
L1
0.4A/
DIV
2 3 4 5 6
V
IN
(V)
V
OUT
ERROR (%)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0
3561 G08
V
OUT
= 1.8V
T
A
= 25°C
I
OUT
= 1.0A
I
OUT
= 400mA
2 3 4 5 6
V
IN
(V)
FREQUENCY VARIATION (%)
10
8
6
4
2
0
–2
–4
–6
–8
–10
3561 G09
V
OUT
= 1.8V
I
OUT
= 1A
T
A
= 25°C
Load Regulation Line Regulation Frequency vs V
IN
1 10 100 1000 10000
LOAD CURRENT (mA)
V
OUT
ERROR (%)
0.4
0.3
0.2
0.1
0
–0.1
–0.2
–0.3
–0.4
–0.5
3561 G07
V
IN
= 3.3V
V
OUT
= 2.5V
Note 8: This IC includes overtemperature protection that is intended to
protect the device during momentary overload conditions. Junction
temperature will exceed 125°C when overtemperature protection is active.
Continuous operation above the specified maximum operating junction
temperature may impair device reliability.