Asynchronous Boost Converter for 10 WLEDs

RT4533/RT4533A

The RT4533/A is a highly integrated LED driver IC capable of driving 10 WLEDs in series. It is composed of a current mode Boost converter integrated with a 36.5V/1.2A power switch. The RT4533/A supports a wide input voltage range from 2.5V to 5.5V and runs at a fixed frequency of 1.1MHz. The LED current is set via an external resistor and the feedback voltage is regulated to 200mV / 300mV.

For brightness dimming, the RT4533/A supports PWM dimming which determines the feedback reference voltage.

Applications

Cellular Phones
Digital Cameras
Probable Instruments

Key Spec.

	RT4533	RT4533A
Status	Active	Active
Vin (min) (V)	2.5	2.5
Vin (max) (V)	5.5	5.5
SW Freq (typ) (kHz)	1100	1100
Number of LEDs (max) (pcs)	10	10
Iout (max)/channel (mA)	30	30
Iq (typ) (mA)	0.35	0.35
Dimming Control	PWM	PWM
Topology	Boost	Boost
Features	Cycle-by-Cycle Current Limit;Enable Input;OVP;Stable with Ceramic Capacitor;UVP	Cycle-by-Cycle Current Limit;Enable Input;OVP;Stable with Ceramic Capacitor;UVP
Package Type	TSOT-26	TSOT-26