MP1527
2A, 1.3MHz
Step-Up Converter
Monolithic Power Systems
Figure 8: Efficiency vs. Load Current (Non-Bootstrapped)
100.00%
95.00%
90.00%
85.00%
Efficiency
80.00%
75.00%
70.00%
65.00%
60.00%
55.00%
50.00%
10
100
Load Current (mA)
1000
VOUT = 12V
VIN=3.3V
VIN=5V
VIN=8V
Figure 9: V
IN
= 5V, V
OUT
= 12V @ 500mA Load
V
IN
= 5V
10µF
100K
IN
4.7µH
Figure 10: Driving Multiple Strings of White LEDs
V
IN
= 2.6
to 25V
4.7µF
1N5819H
W
S
W
M
BR0530
91K
F
B
CM
OP
R
3
10K
C
3
5.6nF
C
4
N/A
C
2
10µF
FAU
LT
O /O
N FF
10nF
10nF
FAULT
E
N
S
S
B
P
V
OUT
= 12
V
@0.5A
1µF
100K
1µF
IN
SW
Up to
6 LEDs
per String
FAULT
ON/OFF
FA
ULT
F
B
E
N
SS
B
P
SGND
10nF
10nF
10K
MP1527
COMP
5.6K
PGND
4.7nF
60
60
60
SN
GD
PN
GD
MP1527 Rev 1.8_8/31/05
Monolithic Power Systems, Inc.
6
MPS [ MONOLITHIC POWER SYSTEMS ]
