MIC2292_11 Datasheet, PDF (1/10 Pages) Micrel Semiconductor – High Frequency PWM White LED Drivers with Internal Schottky Diode and OVP

MIC2292/93C
High Frequency PWM White LED Drivers
with Internal Schottky Diode and OVP
General Description
The MIC2292C and MIC2293C are high frequency, Pulse
Width Modulator (PWM) boost regulators optimized for
constant-current, white LED driver applications. Because
of their constant PWM switching frequencies of 1.6MHz
and 2MHz, respectively, the MIC2292/93C can use the
smallest external components, allowing designers to avoid
sensitive IF bands in their RF applications.
The products feature an internal Schottky diode and two
levels of output overvoltage protection allowing a small
size and efficient DC/DC solution that requires only four
external components.
The 2.5V to 10V input voltage range of MIC2292/3C allows
direct operation from 1- and 2-cell Li Ion as well as 3- to 4-
cell NiCad/NiMH/Alkaline batteries. The MIC2292/3C pro-
ducts are available in a small size 8-pin 2mm × 2mm MLF^®
package and have a junction temperature range of
–40°C to +125°C.
Data sheets and support documentation can be found on
Micrel’s web site at www.micrel.com.
Features
• 2.5V to 10V input voltage
• Output voltage up to 34V
• Internal Schottky diode
• 1.6MHz PWM operation (MIC2292C)
• 2.0MHz PWM operation (MIC2293C)
• Stable with ceramic capacitors
• 15V and 34V output overvoltage protection options
• 500mA switch current rating
• 95mV feedback voltage
• <1% line and load regulation
• <1µA shutdown current
• Over-temperature protection
• UVLO
• 8-pin 2mm × 2mm MLF^® package
• –40°C to +125°C junction temperature range
Applications
• White LED driver for backlighting:
– Cell phones
– PDAs
– GPS systems
– Digital cameras
– MP3 players
– IP phones
• Constant current power supplies
Typical Application
15µH
10µH
Li Ion
MIC2292C-15YML
VIN SW
1µF
OUT
EN
FB ^95mV
GND
0.22µF
16V
Li Ion
MIC2293C-15YML
VIN SW
1µF
OUT
EN
FB ^95mV
GND
0.22µF
16V
1.6MHz PWM White LED Driver with 15V OVP
2MHz PWM White LED Driver with 15V OVP
MLF and MicroLeadFrame are registered trademarks of Amkor Technology, Inc.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel [phone] • fax + 1 [phone] • http://www.micrel.com
September 2009
1
M9999-091509-A