The AME5144 is an efficient driver for up to ten white
LED applications. They are ideal for large LCD backlight
displays in Cell Phone, PDAs, and other handheld devices.
The AME5144 is switch-mode boost converter with constant
LED current, rather than output voltage. The series
connection allows the LED currents to be identical for uniform
brightness and minimizes the number of trace to the
LEDs. The AME5144 drives series-connected LEDs to
controlled-current pin which connected a typically 13W
sense resistor, not an expensive fraction-ohm value.
Fast 1MHz current-mode PWM operation allows for small
input and output capacitors and a small inductor while minimizing
ripple on the input supply/battery. Soft-start eliminates
inrush current during startup. To control LED brightness,
the LED current can be pulsed by applying a single
analog/PWM signal with a frequency range from 200Hz to
30KHz for the control pin CTRL.
The AME5144 is available in space saving, 8 pin, 3mm x
3mm x 0.75mm DFN package.