MP1521
High Efficiency
White LED Driver
Monolithic Power Systems
Absolute Maximum Ratings
Supply Voltage (V
IN
)
Switch Voltage to GND
V
EN
, V
REF
, V
BRT
, V
FB1
, V
FB2
, V
FB3
Storage Temperature
28V
-0.5V to 28V
–0.3V to 6V
-55°C to +150°C
Recommended Operating Conditions
Supply Voltage (V
IN
)
Operating Temperature
Switch Voltage to GND
2.7V to 25V
-20°C to +85°C
-0.5V to 25V
150°C/W
60°C/W
Package Thermal Characteristics
Thermal Resistance,
Θ
JA
(MSOP10)
Thermal Resistance,
Θ
JA
(QFN16)
Electrical Characteristics
(V
IN
= 5.0V, T
A
= 25°C unless specified otherwise)
Parameters
Supply Current (shutdown)
Supply Current (quiescent)
Minimum Off Time, normal
operation
Minimum Off Time, start-up
(Note 1)
UVLO
Under Voltage Lockout
Enable
Threshold
Hysterisis
Leakage Current
Open Load Shutdown
Threshold
Leakage Current
Reference
Output Voltage
Load Regulation
Line Regulation
Feedback Comparator
Threshold
Hysterisis (Note 2)
FB Input Bias Current
PWM Mode
Output-Off Threshold
BRT Input Bias
BRT Full Scale Threshold
(Note 3)
Output Switch
Switch On Resistance (Note 2) R
ON
Switch Current Limit
Leakage Current
Thermal Shutdown (Note 2)
Symbol
I
IN (OFF)
I
IN (ON)
t
OFF (NORMAL)
t
OFF (START)
Condition
Min
V
EN
<0.4V
V
EN
>1.5V, V
BRT
=0V, V
FB
=0V
V
EN
>1.5V, V
BRT
=0.6V
400
V
FB
=0
V
EN
>1.5V, V
BRT
=0.6V,
1.5
V
FB
=0V
V
IN RISING
V
IN FALLING
2.1
1.9
0.8
V
EN
=3V
Measured at OLS Pin
V
OLS
=15V
V
OLS
=25V
I
REF
=0A
I
REF
=0 to 100µA
V
IN
=3 to 15V, I
REF
=0A
V
BRT
=1.2V
V
BRT
=1.2V
V
FB
=0.2V
V
BRT
=0.6V
26
45
1.20
1.235
2.5
2.5
400
30
-50
-30
1.0
60
Typ
1
550
500
Max
3
700
700
2.4
2.6
2.4
2.0
1
29
1
70
1.27
5
5
420
0
0.26
0
1.2
V
IN
=5.0V
300
V
SW
=25V
160
0.5
400
0.6
5
Units
µA
µA
nS
µS
V
V
V
mV
µA
V
µA
µA
V
mV
mV
mV
mV
nA
V
nA
V
Ω
mA
µA
°C
380
-150
0.18
-100
Notes:
1) First 64 pulses after EN switches high.
2) Guaranteed by design.
3) The output current is off when BRT is driven below the output-off threshold and full-scale when driven above the full-scale
threshold. To PWM the output drive BRT above and below these thresholds.
MP1521 Rev 2.7 10/06/04
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MPS [ MONOLITHIC POWER SYSTEMS ]
