
Integrated Silicon Solution
GENERAL DESCRIPTION
The IS31LT3554 is a LED driver based on a highly efficient boost controller operating over a wide input voltage range of 4.5V to 33V.
The IS31LT3554 contains four regulated current sources with 1.5% (Typ.) current matching between strings for a uniform LED brightness. Each current source can be programmed via an external resistor to drive from 20mA to 180mA. A fast slew rate current source allows high frequency and narrow pulse width dimming signals to achieve a very high contrast ratio. The device operating frequency can be adjusted from 0.1MHz to 1MHz.
FEATURES
● Input voltage range: 4.5V to 33V
● 4-Channel LED current sinks, 180mA per string
● LED current adjustable from 20mA to 180mA
● String-to-string current matching accuracy: 1.5%
● Adjustable operating frequency: 100kHz to 1MHz
● External PWM dimming
● High contrast ratio
● Less than 3µA shutdown current
● Programmable soft-start
● Built-in protection features
• OCP, OTP, UVLO
• Open/short LED protection
• Programmable OVP
• Schottky Diode/inductor short-circuit protection
APPLICATIONS
● LCD Monitor/TV
● LED lighting