MP2481 Datasheet, PDF (1/12 Pages) Monolithic Power Systems – 36V, 1.2A, 1.4MHz White LED Driver

The Future of Analog IC Technology
MP2481
36V, 1.2A, 1.4MHz
White LED Driver
DESCRIPTION
The MP2481 is a 36V, 1.2A, white LED driver
suitable for either step-down or inverting
step-up/down applications. It achieves 1.2A
peak output current over a wide input supply
range with excellent load and line regulation.
Current mode operation provides fast transient
response and eases loop stabilization. Fault
condition protection includes thermal shutdown,
cycle-by-cycle peak current limiting, input over
voltage protection, open strings protection and
output short circuit protection.
The MP2481 incorporates both DC and PWM
dimming onto a single control pin. The separate
input reference ground pin allows for direct
enable and/or dimming control for a positive to
negative power conversion.
The MP2481 requires a minimum number of
readily available standard external components
and is available in 8-pin MSOP8E package.
EVALUATION BOARD REFERENCE
Board Number
Mode
EV2481-H-00A
Step-down
EV2481-H-01A
Step-up/down
FEATURES
• 1.2A Maximum Output Current
• Unique Step-up/down Operation (Buck-
Boost Mode)
• Wide 4.5V to 36V Operating Input Range for
Step-Down Applications (Buck Mode)
• 0.30Ω Internal Power MOSFET Switch
• Fixed 1.4MHz Frequency
• Analog and PWM Dimming
• 0.2V Reference Voltage
• Up to 95% Efficiency
• 5μA Shutdown Mode
• No minimum LED required
• Stable with Low ESR Output Ceramic
Capacitors
• Cycle-by-Cycle Over Current Protection
• Thermal Shutdown Protection
• Open Strings Protection
• Input Over Voltage Protection
• Output Short Circuit Protection
• Available in 8-Pin MSOP8E Package
APPLICATIONS
• General LED Illuminations
• LCD Backlight Panels
• Handheld Computers
• Automotive Internal Lighting
• Portable Multimedia Players
• Portable GPS Devices
All MPS parts are lead-free and adhere to the RoHS directive. For MPS green
status, please visit MPS website under Quality Assurance. “MPS” and “The
Future of Analog IC Technology” are Trademarks of Monolithic Power
Systems, Inc.
TYPICAL APPLICATION (STEP-UP/DOWN APPLICATION)
Efficiency vs. Input Voltage
4.5V-36V
VIN
ON OFF
DC or PWM INPUT
1
VDD
3
OVP
7
BST
C1
Cbs
L1
8
SW
MP2481
5
EN/DIM
D1
C2
6 _INGND
VSS
2
FB ⁴
3 series, 9 paralleled
R1
R2
Rs
Step-up/down Application
90
85
80
4 series,400mA
3 series,400mA
75
3 series,9 paralleded,180mA total
70
65
60
0 5 10 15 20 25 30
INPUT VOLTAGE (V)
MP2481 Rev. 1.42
www.MonolithicPower.com
1
4/28/2012
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© 2012 MPS. All Rights Reserved.