LM3552SD/NOPB National Semiconductor, LM3552SD/NOPB Datasheet - Page 14

• Manufacturer Part Number: LM3552SD/NOPB
• Description: IC LED DRIVER PHOTO FLASH 14-LLP
• Manufacturer: National Semiconductor
• Series: PowerWise®r
• Type: Photo Flash LEDr

Specifications of LM3552SD/NOPB

• Topology: PWM, Step-Up (Boost)
• Number Of Outputs: 1
• Internal Driver: Yes
• Type - Primary: Flash/Torch
• Type - Secondary: White LED
• Frequency: 900kHz ~ 1.6MHz
• Voltage - Supply: 2.7 V ~ 5.5 V
• Voltage - Output: 10.6 V ~ 12.4 V
• Mounting Type: Surface Mount
• Package / Case: 14-LLP
• Operating Temperature: -40°C ~ 85°C
• Current - Output / Channel: 1A
• Internal Switch(s): Yes
• Efficiency: 93%
• For Use With: LM3552SDEV - BOARD EVALUATION LM3552SD
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: LM3552SD; LM3552SDNOPB; LM3552SDNOPBTR; LM3552SDNOPBTR; LM3552SDTR

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DUAL-MODE CONFIGURATION
Using the Dual-Mode configuration with either the LM3551/2,
a 5V, high current rail (approx. 700mA total) can be created
while still allowing for a high flash with a true load disconnect.
R1 and R2 setup the +5V following the equation:V
× (1 + R1/R2) . When the LM3551/2 is on, and the T/F pin is
low (logic '0'), the part will provide a regulated output voltage
that can be used to provide a voltage rail within a system. By
setting the T/F pin high, the LM3551/2 will allow the current
R
OUT
1
= 29.5kΩ,R
= 1.265
I
FLASH
2
= 500mA
14
= 10kΩ R
to flow through the flash LED while still maintaining the fixed
output voltage rail. The flash current is set by R
equation R
exceed 500mA. The total usable output current is dependent
upon the output voltage selected. If the dual-mode configu-
ration is used, the FTO pin should be grounded to prevent the
voltage rail from being shutdown at an unwanted time.
F
= 3Ω
F
= [(V
OUT
- V
LED
) / I
LED
20151209
] - 0.36Ω , and should not
F
using the