AOZ1978 Datasheet, PDF (1/17 Pages) Alpha & Omega Semiconductors – Dual Channel High Voltage LED Driver IC

AOZ1978
Dual Channel High Voltage
LED Driver IC
General Description
The AOZ1978 is a dual-channel high-efficiency LED
driver controller for high voltage LED backlighting
applications. It is designed to independently drive
two high-brightness LED light bars in LED TV
applications. The AOZ1978 can support a wide
range of input and output voltages. The input bias
voltage range of AOZ1978 is from 8V to 18V.
The AOZ1978 has multiple features to protect the
regulator under fault conditions. A control pin can
disable an external switch to disconnect the LEDs
current path from the output in PWM dimming or
under catastrophic failure conditions. Cycle-by-cycle
current protection limits the peak inductor current.
Thermal shutdown provides another level of
protection. An output flag to indicate the fault
condition if output of any channel is shorted to
ground.
Low feedback voltage (500mV) helps to reduce
power loss.
The AOZ1978 is available in a standard SO-20
package and operates over the temperature range of
-40C to +85C.
Typical Application
Features
 8V to 18V input bias voltage
 180⁰ Out of phase channel switching provides
input ripple current cancellation
 18V driving capability at GATE pins
 Disconnect control pin for PWM dimming or fault
conditions
 Flag to indicate output short or fault condition
 500mV feedback regulation
 External reference input and Analog Dimming
capability
 8 bit PWM dimming resolution
 Cycle-by-cycle current limit
 Output over-voltage protection
 LED short and open protection
 Thermal shutdown protection
 SO-20 package
Applications
 LCD TV LED backlight
Rev. 1.0 January 2012
www.aosmd.com
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