Datasheet

ADP1649 Data Sheet
Rev. 0 | Page 12 of 28
ASSIST LIGHT
The assist light mode provides a continuous current that is
programmable from 25 mA to 200 mA. Set the assist light
current using the I_TOR bits (in Register 0x03).
To enable assist, set LED_MOD to assist light mode and set
OUTPUT_EN = 1 (in Register 0x04). Disable assist light mode by
setting LED_MOD to standby mode or setting OUTPUT_EN = 0.
Figure 24. Enabling and Disabling Assist Light Mode
FLASH MODE
Flash mode provides 300 mA to 1 A for a programmable time of
up to 1.6 seconds. Set the flash current using the I_FL bits (in
Register 0x03) and the maximum flash duration with the FL_TIM
bits (in Register 0x02). To enable flash mode, set LED_MOD
to flash mode and set OUTPUT_EN = 1. Enable flash without
the STROBE pin by setting STR_MODE (in Register 0x04) to 0
(software strobe).
When STR_MODE is in hardware strobe mode, setting the
STROBE pin high enables flash and synchronizes it to the image
sensor. Hardware strobe mode has two modes for timeout: level
sensitive (STR_LV = 1, Register 0x04) and edge sensitive
(STR_LV = 0, Register 0x04).
Figure 25. Flash Operation: Level Sensitive Mode
In level sensitive mode, the duration of the STROBE pin set to
high sets the duration of the flash up to the maximum time
indicated by the FL_TIM timeout. If STROBE remains high
longer than the duration set by FL_TIM, a timeout fault
disables the flash.
Figure 26. Flash Operation: Edge Sensitive Mode
In edge sensitive mode, a positive edge on the STROBE pin
enables the flash, and the FL_TIM bits set the flash duration.
ASSIST TO FLASH OPERATION
Figure 27. Enabling Assist to Flash (Level Sensitive) Mode
The STR_POL bit in Register 0x07 changes the default enable of
the STROBE pin from low to high and from high to low. Additional
image sensor specific assist/flash enable modes are included in
the device, and information on these modes is available by request
from the Analog Devices, Inc., sales team.
TORCH MODE
Set the assist/torch light current modes using the I_TOR bits.
To enable torch mode using a logic signal, set LED_MOD to
standby mode, set OUTPUT_EN = 1, and bring GPIO1 high.
Disable the external torch mode by setting GPIO1 low or pro-
gramming OUTPUT_EN = 0. Bringing GPIO1 low during torch
mode automatically sets OUTPUT_EN = 0. To reenable torch
mode, program OUTPUT_EN = 1 and bring GPIO high again.
Figure 28. Enabling External Torch Mode Using GPIO1
LED CURRENT
REG 0x03, I_TOR = XXX mA
REG 0x04, OUTPUT_EN = 1
LED_MOD = 10
I
2
C DATA BUS
REG 0x04, OUTPUT_EN = 0
0A
I
ASSIST
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LED CURRENT
REG 0x04, OUTPUT_EN = 1
STR_LV = 1
LED_MOD = 11
I
2
C DATA BUS
0A
I
FLASH
STROBE
REG 0x02, FL_TIM = XXXX ms
REG 0x03, I_FL = XXXXX mA
ADP1649 SETS OUTPUT_EN TO 0.
ADP1649 SETS LED_MOD TO 00.
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I
2
C DATA BUS
LED CURRENT
REG 0x02, FL_TIM = XXXX ms
REG 0x03, I_FL = XXXXX mA
REG 0x04, OUTPUT_EN = 1
STR_LV = 0
LED_MOD = 11
0A
I
FLASH
STROBE
ADP1649 SETS OUTPUT_EN TO 0.
ADP1649 SETS LED_MOD TO 00.
FL_TIM
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LED CURRENT
REG 0x02, FL_TIM = XXXX ms
REG 0x03, I_TOR = XXX mA
REG 0x03, I_FL = XXXXX mA
REG 0x04, OUTPUT_EN = 1
STR_LV = 1
LED_MOD = 10
I
2
CDATABUS
0A
I
FLASH
STROBE
ADP1649 SETS OUTPUT_EN TO 0.
ADP1649 SETS LED_MOD TO 00.
I
ASSIST
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LED CURRENT
REG 0x03, I_TOR = XXX mA
REG 0x04, OUTPUT_EN = 1
LED_MOD = 00
I
2
C DATA BUS
0A
I
ASSIST
ADP1649 SETS OUTPUT_EN TO 0
GPIO1 (TORCH)
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