CM9130 Datasheet, PDF (1/12 Pages) California Micro Devices Corp – Three Output Driver for White LEDs

PRELIMINARY
Three Output Driver for White LEDs
CM9130
Features
• 2.9V to 6V input voltage range
• Powers display backlight and/or flash WLED
• Low external parts count, requires no inductor and
ballast resistors
• Low EMI and reflected ripple
• Adaptive charge pump ratio (1x or 1.5x) maximizes
efficiency at both high and low input voltages
• Precision regulation for each output with 2% cur-
rent matching at 20mA
• Programmable LED current via ISET pin
• Typical 500 KHz fixed switching frequency
• Supports up to 300mA, drives three LEDs regu-
lated to 50mA each
• Analog and PWM intensity control
• Less than 10µA shutdown current
• Over-current and over-temperature protection
• Undervoltage lockout
• Soft-start limits start-up inrush current
• TQFN-16 package
• Optional RoHS compliant lead free packaging
Applications
• Drives white LEDs for STN/TFT Color LCD back-
lighting
• Cell phones, PDAs
• Digital Still Cameras
• Flash for DSC
Product Description
The CM9130 is an adaptive fractional switched capaci-
tor (charge pump) regulator optimized for driving 3
white LEDs. Each LED's driver current is matched to
within 2% for uniform intensity. It supports an input volt-
age range of 2.9V to 6V, with undervoltage lockout. A
failure detection circuit prevents the loss of power when
one or more LEDs fail (short or open). Internal over-
temperature and over-current management provide
short circuit protection.
The CM9130 regulates up to 300mA of output current
to drive WLEDs, allowing up to 50mA per LED channel.
The maximum LED current is programmed with an
external resistor. The EN input allows for Analog and
PWM brightness control. The CM9130 can also be
used for a camera flash. In full shutdown mode, the
CM9130 draws only 10µA.
The CM9130 automatically selects the most efficient
charge pump ratio based on the operating voltage
requirement of the white LEDs. The proprietary design
architecture maintains high efficiency (> 80%), and at
low V_IN provides longer battery life. With a high V_IN, or
when the adapter is powered, it provides cool reliable
operation.
The CM9130 is available in a compact 16 lead TQFN
package. It can operate over the industrial temperature
range of -40°C to 85°C.
Typical Application
1.0uF
1.0uF
C1P C1N C2P C2N
2.9V to 6.0V
VIN
VOUT
1uF
1uF
PhotonIC^TM
CM9130 ^LED1
on ^Enable
EN
off
LED2
LED3
ISET
R_SET
GND
© 2006 California Micro Devices Corp. All rights reserved.
04/26/06 490 N. McCarthy Blvd., Milpitas, CA 95035-5112 l Tel: [phone] l Fax: [phone] l www.cmd.com
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