ISL97900 Datasheet, PDF (1/2 Pages) Intersil Corporation – RGB Buck-Boost 3-Channel Color Sequencing LED Driver

DATASHEET
To request the full datasheet, please visit www.intersil.com/products/isl97900
RGB Buck-Boost 3-Channel Color Sequencing LED
Driver
ISL97900
The ISL97900 is a highly efficient 3-channel, 1.5A sequential
LED driver powered from a single-cell Li-ion battery, or
regulated input voltage up to 5.5V. This LED driver incorporates
an independent current controlled driving mechanism for each
of the LED's, which allows accurate current control of the LED
brightness.
The ISL97900 utilizes a buck-boost converter to ensure that
optimum output voltage is maintained for a wide range of LED
forward voltages. The integrated buck-boost converter
operates well over 90% efficiency across a wide range of
operating conditions. The power conversion core implements a
proprietary algorithm that allows seamless transitions and
glitch-free operation between the buck and the boost modes
as the battery voltage drops during operation.
The ISL97900 architecture includes a 10-bit DAC, which
controls the LED currents. Each of the LED currents can be
programmed through serial interface.
The ISL97900 also includes the Dynamic Headroom
Management function to provide seamless adjustment for the
LEDs’ voltages, which reduces power consumption.
Features
• Buck-boost based LED driver
• RGB color sequencing
• Up to 1.5A output current
• I²C Interface
• 150mV feedback voltage reference for current regulation to
maximize efficiency
• 2.5MHz switching frequency
• Programmable output voltage and output current for each
LED
• Dynamic headroom management
• Internal current setting registers
• Ambient temperature range: 0°C to +70°C
• Pb-free (RoHS compliant)
Applications
• LED-based pico projector in mobile phones
• Stand-alone pico projectors
• Tri-stimulus display drivers
• Other handheld display drivers
C3 C11 C1
22µF 22µF 22µF
L2
2.2µH
C2
10µF
C4
22µF
C5 C6
1µF 10µF
1.8V
SCL
SDA
CEN
BATT
2.8V TO 4.3V
LCoS
DRIVER ASIC
SGND
C10 C7
1µF 0.1µF
1 PVIN
2 ADDR
3 SCL
4 SDA
5 CEN
6 VCC
7 CBYP
8 SGND
THERMAL
PAD
(GND)
VOUT 22
LED1 21
LED2 20
LED3 19
NC 18
NC 17
FB 16
SGND 15
R1
0.1
EN3
EN2
EN1
November 19, 2012
1
FN8372.0
FIGURE 1. TYPICAL APPLICATION
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774 | Copyright Intersil Americas Inc. 2012. All Rights Reserved
Intersil (and design) is a trademark owned by Intersil Corporation or one of its subsidiaries.
All other trademarks mentioned are the property of their respective owners.