KTD2686
August 2020 – Revision 04b Page 1 Company Confidential
Features
• High efficiency synchronous boost converter
with 2MHz/4MHz switching frequency option
• I
2
C interface programming and hardware
STROBE/TORCH control
• Two current sources and one current sink
LED1: Up to 1.5A (7 bits)
LED2: Up to 1.0A (6 bits)
LED3: Up to 0.5A (6 bits)
Flash/Torch/IR modes
Independent LED on/off and current settings
Programmable ramp shape and time control
Three input low voltage protection modes
Flash time-out protection up to 1.44s
LED cathode ground connection for improved
thermal dissipation (LED1/LED2)
• LED open/short protection
• I
2
C fault read back (I
2
C address = 0x63)
Applications
• Smartphones and Tablets Camera Flash
• Digital Cameras
Brief Description
KTD2686 is the ideal power solution for high-power flash
LEDs. It includes a highly integrated synchronous boost
converter, two current sources and one current sink,
providing a very small total solution in portable application.
It has both I
2
C interface and hardware STROBE/TORCH
pins for maximum control flexibility. The two integrated
current sources and one current sink are independently
controlled, their on/off conditions and current settings in
Flash/Torch/IR modes can be programmed independently
by the I
2
C interface. It also has three selectable input low
voltage protection modes to prevent a system reset under
low battery condition. Thermal regulation is also integrated
to limit the IC temperature and continuously provide the
maximum output current.
Various protection features are integrated into KTD2686,
including cycle-by-cycle input current limit protection,
output over-voltage protection, LED fault (open or short)
protection, flash timeout protection and thermal shutdown
protection.
KTD2686 is available in a RoHS and Green 12-ball
1.42mm x 1.66mm WLCSP package with 0.4mm pitch.
Typical Application
LX
VOUT
LED1
LED2
VIN
SDA
SCL
TORCH
STROBE
TX
GND
I
2
C, SDA
I
2
C, SCL
GPIO-TORCH
GPIO-STROBE
GPIO-TX
C
OUT
10µF
L
1.0µH
C
IN
10µF
MCU
VIN
2.7V ~ 5.5V
Flash LEDs
LED1 Up to 1.5A
LED2 Up to 1.0A
LED3 Up to 0.5A
LED3
Three-Channel Flash LED Driver with Independent Current Control
KTD2686
August 2020 – Revision 04b Page 2 Company Confidential
Pin Descriptions
Pin #
Name
Function
A1
GND
Ground pin
A2
VIN
Input supply pin for the device. Connect a 10µF ceramic capacitor to GND.
A3
SDA
Bi-direction data pin of the I²C interface.
B1
LX
Switching pin of the boost converter.
B2
STROBE
Active high FLASH/IR enable pin. There is an internal 300kΩ pull-down resistor at
this pin to GND.
B3
SCL
Clock input pin of the I²C interface.
C1
VOUT
Output pin of the boost converter. Connect a 10µF ceramic capacitor to GND
C2
LED3
Regulated output current sink, up to 0.5A.
C3
TORCH
Active high TORCH enable pin. There is an internal 300kΩ pull-down resistor at this
pin to GND.
D1
LED2
Regulated output current source #2, up to 1.0A.
D2
TX
Active high power amplifier synchronization input pin.
D3
LED1
Regulated output current source #1, up to 1.5A.
WLSCP-12
12-Bump 1.42mm x 1.66mm x 0.62mm
WLCSP Package
Top Mark
WW = Device ID Code,
XX = Date Code, YY = Assembly Code,
ZZZZ = Serial Number
TOP VIEW TOP VIEW
WW
XXYY
ZZZZ
C
B
A
1 2 3
GND
LX
VOUT
VIN
STRB
LED3
SDA
SCL
TRCH
LED2 TX LED1
D