Datasheet

LTC3542
13
3542fa
Figure 3a. Typical Application
Figure 3b. Layout Diagram
Figure 3c. Effi ciency Curve
Figure 3d. Load Step
V
IN
LTC3542
RUN
R1
75k
*SUMIDA CDRH2D18HD-2R2NC
**TDK C2012X5R0J106M
3542 F03a
R2
150k
C
F
22pF
L*
2.2μH
C
IN
**
10μF
C
OUT
**
10μF
SW
V
IN
2.7V TO 5.5V
V
OUT
1.8V
500mA
V
FB
MODE/SYNC
GND
1
2
3
V
FB
R1
V
IN
V
IN
GND
3542 F03b
C
IN
6
5
GND
4
RUN
GND
GND
VIA TO V
OUT
MODE/
SYNC
SW
R2
C
F
C
OUT
L
V
OUT
OUTPUT CURRENT (mA)
30
EFFICIENCY (%)
90
100
20
10
80
50
70
60
40
0.1 10 100 1000
3542 G17
0
1
V
IN
= 2.7V
V
IN
= 3.6V
V
IN
= 4.2V
V
OUT
= 1.8V
Burst Mode OPERATION
FIGURE 3a CIRCUIT
V
OUT
100mV/DIV
AC COUPLED
I
L
500mA/DIV
V
IN
= 3.6V
V
OUT
= 1.8V
I
LOAD
= 0mA TO 500mA
FIGURE 3a CIRCUIT
20μs/DIV
3542 G06
I
LOAD
500mA/DIV
APPLICATIONS INFORMATION