AN10712_15 Datasheet, PDF (4/14 Pages) NXP Semiconductors – Photo flash LED driver

NXP Semiconductors
AN10712
Photo flash LED driver
V_bat
battery
PGND
Cin
10 μF
PGND
control
signals
L
2.2 μH
LX
VIN
VO
SSL3252
TORCH
STRB/2LED
SDA/EN2
SCL/EN1
IF_SEL⁽¹⁾
LED
I_IND
Cout
10 μF
PGND
flash LEDs
PGND
indicator LED
GND
PGND
002aaf151
PGND
(1) The selection of the mode of the IC is done with I²C. IF_SEL must be connected to VIN.
Fig 1. Typical application diagram of SSL3252 using I²C control
2.2.2 Direct enable control mode
Using the SSL3252 as shown in Figure 2 is the typical application for the SSL3252 in
Direct enable control mode. It has the advantage of operating the driver without using I²C
communication. This provides a short response time and a less complicated operation,
minimizing flash-ON latency. However, it has less flexible control features for the different
operating modes. The STRB/2LED pin is functioning as 2LED output.
V_bat
battery
PGND
Cin
10 μF
PGND
control
signals
L
2.2 μH
LX
VIN
VO
SSL3252
TORCH
STRB/2LED
SDA/EN2
SCL/EN1
IF_SEL⁽¹⁾
LED
I_IND
Cout
10 μF
PGND
flash LEDs
PGND
indicator LED
GND
PGND
002aaf152
PGND
(1) The selection of the operational mode of the IC is done with EN1 and EN2. IF_SEL must be
connected to GND.
Fig 2. Typical application diagram of SSL3252 using Direct enable control
AN10712
Application note
All information provided in this document is subject to legal disclaimers.
Rev. 1 — 28 October 2011
© NXP B.V. 2011. All rights reserved.
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