AS3685A Datasheet, PDF (1/2 Pages) ams AG – Ultra Small High Efficiency 700mA Charge Pump for White LED Flash

AS3685A/AS3685B
Product Brief
austriamicrosystems
Product Brief
AS3685A/AS3685B
Ultra Small High Efficiency 700mA Charge Pump for White LED Flash
1 General Description
The AS3685 is low noise high efficiency capacitive
charge pump with 1:1, 1:1.5 and 1:2 operating
modes in a small 3x3mm DFN10 or a tiny 2x1.5mm
WL-CSP (Wafer Level Chip Scale Package)
package. It can drive one flash led at up to 700mA
current. It supports flash/torch and indicator mode
for the flash led.
Additionally the AS3685 limits the flash time
automatically to protect the flash LED.
2 Key Features
High Efficiency capactive charge pump with 1:1,
1:1.5 and 1:2 modes
− 1:2 Mode can be disabled
(factory programmable)
Up to 700mA Led Current
Automatic Charge Pump Mode switching (Up)
LED cathode disconnect in Shutdown
Overtemperature Protection
Automatic 800ms Flash Timeout to protect the
flash LED (time factory programmable)
Two Device Variants:
− AS3685A: Direct control to select three
currents
− AS3685B: Single Pin Interface or Two Pin
Interface with Strobe Input; 17 different
currents can be selected
Package
− DFN10 3x3mm (10 pins + exposed pad)
− WL-CSP (Wafer Level Chip Scale Package)
3x4 balls 0.5mm pitch (2x1.5mm)
3 Application
Flash / Torch for Mobile Phones, Digital
Cameras and PDA
4 Application Diagram
Figure 1 – Application Diagram of AS3685A/AS3685B
CFLY1 1.0 F
CFLY2 1.0 F
VBAT
CBAT
2.2 F
C1+ C1- C2+ C2-
VBAT
VCP
AS3685A
EN1 ^AS3685B
ILED
EN2
ISET VSS
CVCP
2.2 F
DLED
RTXMASK
RISET
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Revision 2.0 / 20060726
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