Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

203795A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice • December 8, 2015

1

PRODUCT SUMMARY

SKY81299: 2.4 A Two-Channel Flash LED Driver

Applications

 LED photo flash with Movie/Torch mode

 Dual LED flash with color compensation

 “Selfie” flash for front-facing camera (PIP enabled)

 Smartphones/tablets

Features

 Input voltage range: 2.5 V to 5.5 V

 Each channel can program to 1.5 A with 12 mA programming

step size; up to 2.4 A total combined output current

 > 90% LED efficiency at 250 mA

> 85% LED efficiency at 1 A

 2.75 MHz switching frequency

 Soft-start and input current limit

 Separate flash enable/flash inhibit

 Programmable blinking LED notification

 Flash and Movie mode current

 Input voltage monitor with programmable thresholds

 Current read-back in input voltage monitor operation

 Programmable safety timer

 Fault read back

 Fault protection

 Integrated safety timer

 Over-voltage (open LED, open circuit)

 Short circuit

 Over-temperature protection

 Flash mode input voltage monitor

 Open-drain fault output

 −40 C to +85 C temperature range

 Small WLCSP (16-bump, 1.903  1.903  0.605 mm, 0.4 mm

pitch) package (MSL1, 260

C per JEDEC J-STD-020)

Description

The SKY81299 is a high-efficiency, 2.4 A high-current boost

converter with two independently programmable constant current

outputs. The device is intended for LED photo flash/facial

recognition and “selfie” front-facing camera flash applications in

all single-cell Li-ion powered portable products.

The SKY81299 maintains the flash LED output current using a

DC-DC step-up converter with a bypass function to maximize

efficiency under all load conditions. The flash current for each

channel can be programmed up to 1.5 A at 12 mA step. The

device uses a common cathode (current source) topology to allow

a direct flash LED cathode connection to the ground plane which

facilitates LED heat dissipation. The total combined output current

for flash outputs is 2.4 A.

The high-frequency 2.75 MHz DC-DC boost switching frequency

allows the use of a small external inductor and output capacitor,

which makes the SKY81299 ideally suited for small battery-

powered applications. A startup control circuit automatically

senses the flash LED forward voltage at any programmed output

current setting and determines the most efficient operation mode.

SKY81299 LED Flash and Movie modes. Device operations are

fully configurable; Movie and Flash current level, current limits,

separate flash enable inputs to initiate the flash operation and a

flash inhibit input either to reduce the flash current to Movie-

mode levels or to shut off the flash current during high battery

demand conditions.

The SKY81299 is available in a small 1.903

 1.903  0.605 mm,

16-bump Wafer-Level Chip Scale (WLCSP) package.

A typical application circuit is shown in Figure 1.

all applicable legislation and are halogen-free.

For additional information, refer to

Skyworks

SQ04–0074.