LM3554TME/NOPB National Semiconductor, LM3554TME/NOPB Datasheet - Page 32

• Manufacturer Part Number: LM3554TME/NOPB
• Description: IC LED DVR PHOTO FLASH 16-USMD
• Manufacturer: National Semiconductor
• Type: Photo Flash LED (I²C Interface)r

Specifications of LM3554TME/NOPB

• Constant Current: Yes
• Topology: High Side, Step-Up (Boost)
• Number Of Outputs: 2
• Internal Driver: Yes
• Type - Primary: Flash/Torch
• Type - Secondary: White LED
• Frequency: 2MHz
• Voltage - Supply: 2.7 V ~ 5.5 V
• Voltage - Output: 5V
• Mounting Type: Surface Mount
• Package / Case: 16-MicroSMD
• Operating Temperature: -30°C ~ 85°C
• Current - Output / Channel: 600mA
• Internal Switch(s): Yes
• Efficiency: 90%
• Led Driver Application: LED Backlighting, Portable Electronics
• No. Of Outputs: 2
• Output Current: 1.2A
• Input Voltage: 2.7V To 5.5V
• Dimming Control Type: I2C
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: LM3554TMETR

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CONFIGURATION REGISTER 1
Configuration Register 1 holds the light load disable bit, the
voltage mode select bit (OV), the external flash inhibit bit, the
control bit for the LEDI/NTC pin, the control bit for ENVM to
interrupt input
TORCH pin is
Torch Mode
TORCH is a
a hardware
(Hardware
TX1 flash
(default)
0 = TX1/
1 = TX1/
Enable)
TORCH
enable
Bit 7
0 = ENVM/TX2
pin is an active
1 = ENVM/TX2
pin is an active
Bit 6 (TX2
high Flash
low Flash
Polarity)
(default)
inhibit
inhibit
ENVM/TX2 pin
Voltage Mode.
TX2 is a Power
Flash to Torch
is a logic input
1 = TX2 Mode
Synchronizati
Bit 5 (ENVM/
LM3554 from
Output Mode
will force the
The ENVM/
ENVM/TX2
ENVM/TX2
on input. A
0 = ENVM
Mode The
A high on
to enable
(default)
will force
Amplifier
Voltage
high on
mode.
TX2)
FIGURE 20. Configuration Register1 Description
TABLE 6. Configuration Register 1 Bit Settings
Reads Back '0' 0 = LEDI/NTC
Bit 4 (N/A)
32
pin in Indicator
pin in Thermal
1 = LEDI/NTC
Bit 3 (LEDI/
Comparator
current is
disabled.
(default)
Indicator
TX2 mode, the polarity selection bit for the TX2 input, and the
control bit for the TX1/TORCH bit (see
6).
Mode.
mode
NTC)
Bit 2 (External
Input Disabled
Flash Inhibit)
Input Enabled
0 = STROBE
1 = STROBE
(default)
voltage is 4.5V
voltage is 5V
Mode output
Mode output
0 = Voltage
1 = Voltage
Bit 1 (OV,
(default)
Voltage
Output
Select)
Figure 20
30042025
(Disable Light
LM3554 will go
load (default).
0 = Light load
comparator is
1 = Light load
comparator is
disabled. The
PFM mode at
enabled. The
mode at light
LM3554 will
not go into
light load.
into PFM
Load )
Bit 0
and
Table