LM3554TME/NOPB National Semiconductor, LM3554TME/NOPB Datasheet
LM3554TME/NOPB
Specifications of LM3554TME/NOPB
Related parts for LM3554TME/NOPB
LM3554TME/NOPB Summary of contents
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... TX event has occurred, a flag indicating the flash timeout counter has expired, a flag indicating the devices die temperature has reached the ther- mal shutdown threshold, and a flag indicating an open or short LED. Typical Application Circuits © 2011 National Semiconductor Corporation LM3554 2 C-Compatible Interface Features ■ ...
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Application Circuit Component List Component Manufacturer L TOKO COUT Murata CIN Murata LEDs Lumiled Connection Diagram Pin Descriptions Pin Name A1 LED1 High-Side Current Source Output for Flash LED. A2, B2 OUT Step-Up DC/DC Converter Output. A3 Drain ...
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... J-MAX Storage Temperature Range Maximum Lead Temperature (Soldering) ESD Caution Notice National Semiconductor recommends that all integrated circuits be handled with appropriate ESD precautions. Failure to observe proper ESD handling techniques can result in damage to the device. Electrical Characteristics Limits in standard typeface are for T A ≤ ...
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Symbol Parameter LEDI/NTC bit I Indicator Current LED/NTC = 0 Comparator Trip LEDI/NTC bit = 1, 2.7V V TRIP Threshold 5.5V Switching f 2.7V SW Frequency Quiescent I Device Not Switching Q Supply Current Shutdown I 2.7V SHDN Supply Current ...
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... J Note 4: For detailed soldering specifications and information, please refer to National Semiconductor Application Note 1112: Micro SMD Wafer Level chip Scale Package (AN-1112) Note 5: In applications where high power dissipation and/or poor package thermal resistance is present, the maximum ambient temperature may have to be derated ...
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Typical Performance Characteristics = 0.15Ω), FDSE0312-2R2 (2.2µ LED Efficiency vs V (Single LED TOKO FDSE0312-2R2) Input Current vs V (Single LED TOKO FDSE0312-2R2) LED Efficiency vs V (Dual LED' ...
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Efficiency vs I OUT (Voltage Output Mode 5V) OUT 30042055 OUT OUT (Voltage Output Mode 5V) OUT 30042057 Torch Current Matching vs Code (V = 3.6V 3.2V, IN LED1 ...
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Torch Current 3.2V +85°C, 75mA setting) LED1 LED2 A Flash Current Matching vs Code (V = 3.6V LED1 T = -40°C to +85°C, A Flash Current vs V ...
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Switching Frequency vs V Active (Non-Switching) Supply Current 1.5V) LED Closed Loop Current Limit vs V (Flash Duration Register bits [6:5] = 00, Shutdown Current 30042089 Active (Switching) Supply Current ...
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Closed Loop Current Limit vs V (Flash Duration Register bits [6:5] = 10, V Monitor Thresholds vs Temperature IN Short Circuit Current Limit vs V www.national.com Closed Loop Current Limit (Note 8)) (Flash Duration Register bits [6:5] ...
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Indicator Current (Torch Brightness Register bits[7:6] = 01) Indicator Current (Torch Brightness Register bits[7:6] = 11) Startup into Flash Mode Single LED I = 1.2A FLASH Channel 1: V (2V/div) ...
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Torch Mode to Flash Mode Transition Single LED I = 295mA, I TORCH FLASH Channel 1: V (5V/div) OUT Channel 4: I (500mA/div) LED Channel 2: I (1A/div) L Channel 3: STROBE (5V/div) Time Base: (100µs/div) TX1 Interrupt Operation, TX1 ...
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Load Transient V = 3.6V IN (Voltage Output Mode, V Channel 1: V (500mV/div, AC Coupled) OUT Channel 4: I (200mA/div) OUT Channel 2: I (500mA/div) L Time Base: (40µs/div) Flash Pulse to HWEN Low Single LED 1.2A ...
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Flash Pulse + V to Flash Pulse OUT Single LED 1.2A, V LED Channel 1: V (2V/div) OUT Channel 4: I (500mA/div) LED Channel 2: IL (1A/div) Channel 3: ENVM (5V/div) Time Base: (100µs/div) V Monitor Response IN ...
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Block Diagram Overview The LM3554 is a high-power white LED flash driver capable of delivering up to 1.2A of LED current into a single LED 600mA into two parallel LEDs. The device incorporates a 2MHz constant frequency, ...
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Flash pulse is forced to the Torch current setting, or into shut- down depending on the NTC Shutdown bit setting . Control of the LM3554 is done via an I face. This includes switch-over from LED to Voltage Output mode, ...
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MAXIMUM LOAD CURRENT (VOLTAGE MODE) Assuming the power dissipation in the LM3554 and the am- bient temperature are such that the device will not hit thermal shutdown, the maximum load current as a function of I Where η is efficiency ...
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Maximum Output Power (Led Boost Mode) In LED mode with V > V the LM3554’s boost converter OUT IN will switch and make 0.3V. In this situation the OUT LED total power dissipated in the LM3554 ...
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FLASH TERMINATION (STROBE-INITIATED FLASH) Bit [7] of the Flash Brightness Register (STR bit) determines how the Flash pulse terminates with STROBE-initated flash pulses. With the STR bit = 1 the Flash current pulse will only terminate by reaching the end ...
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Torch Brightness Register set the 4 different indicator current levels. The LEDI current source has a 1V typical headroom voltage. Thermal Comparator Mode (NTC) Writing a (1) to Configuration Register 1 bit [3] disables the indicator current source and ...
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LM3554 TIMING DIAGRAMS FIGURE 3. Normal Torch to Flash Operation (Default, Power On or RESET state of LM3554) FIGURE 4. TX1 Event During a Flash Event (Default State,TX1/TORCH is an Active High TX Input) FIGURE 5. TX1 Event Before and ...
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FIGURE 6. STROBE Input is Level Sensitive (Default State, STR bit = 0) FIGURE 7. STROBE Input is Edge Sensitive (STR bit = 1) www.national.com 22 30042040 30042041 ...
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FIGURE 8. ENVM/TX2 Pin is Configured as an Active High TX Input FIGURE 9. ENVM/TX2 Pin is Configured as an Active Low TX Input 23 30042042 30042043 www.national.com ...
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FIGURE 10. Alternative External Torch Mode (TX1/TORCH Turns on Before STROBE) FIGURE 11. Alternative External Torch Mode (STROBE Goes High Before TX1/TORCH, Same as Default with SEM = 0) FIGURE 12. TX1/TORCH Configured as a Hardware Torch input www.national.com 24 ...
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FLAGS REGISTER AND FAULT INDICATORS The Flags Register (0xD0) contains the Interrupt and Fault indicators. Five fault flags are available in the LM3554. These include a Thermal Shutdown, an LED Failure Flag (LEDF Timeout indicator Flag (TO), a ...
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I 2 C-Compatible Interface START AND STOP CONDITIONS The LM3554 is controlled via an I START and STOP conditions classify the beginning and end of the session. A START condition is defined as SDA The I 2 ...
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TRANSFERRING DATA Every byte on the SDA line must be eight bits long, with the most significant bit (MSB) transferred first. Each byte of data must be followed by an acknowledge bit (ACK). The acknowl- edge related clock pulse (9th ...
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Register Descriptions Register Name Torch Brightness Flash Brightness Flash Duration Flag Register Configuration Register 1 Configuration Register 2 GPIO Register VIN Monitor Register TORCH BRIGHTNESS REGISTER Bits [2:0] of the Torch Brightness Register, or bits [2:0] of the Flash Brightness ...
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FLASH BRIGHTNESS REGISTER Bits [2:0] of the Torch Brightness Register, or bits [2:0] of the Flash Brightness Register place the device in shutdown or control the on/off state of Torch, Flash, the Indicator LED and the Voltage output mode. Writing ...
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FLASH DURATION REGISTER Bits [4:0] of the Flash Duration Register set the Flash Timeout duration. Bits [6:5] set the switch current limit. Bit [7] defaults as a '1' and is not used (see Table 4). Bit 7 (Not Bit 6 ...
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FLAGS REGISTER The Flags Register holds the status of the flag bits indicating LED Failure, Over-Temperature, the Flash Timeout expiring, Bit 7 (V Bit 6 Bit 5 (LED IN (Unused) Thermal Monitor Fault Fault) Fault) 0=No Fault at Not Used ...
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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 Bit 7 Bit 6 ...
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CONFIGURATION REGISTER 2 Configuration Register 2 contains the bits to select if TX2, NTC, and the VIN monitor force Torch mode or force the Flash FIGURE 21. Configuration Register 2 Description Bit 7 (Not Bit 6 (Not Bit 5 (Not ...
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Bit 7 (Not Bit 6 (NTC Bit 5 (ENVM/ Used) External Flag) TX2/GPIO2 Reads Back ' NTC This bit is the External Flag read or write mode is data for the disabled ENVM/TX2/ (default) GPIO2 pin in GPIO ...
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Applications Information OUTPUT CAPACITOR SELECTION The LM3554 is designed to operate with a at least a 4.7µF ceramic output capacitor in LED mode and a 10µF output ca- pacitor in Voltage Output Mode. When the boost converter is running the ...
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NTC THERMISTOR SELECTION NTC thermistors have a temperature to resistance relation- ship of: where β is given in the thermistor datasheet and R thermistors value at +25° Figure equal to: where R(T) is the thermistors ...
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FIGURE 25. Thermistor Voltage Divider and Sensing Circuit NTC THERMISTOR PLACEMENT The termination of the thermistor must be done directly to the cathode of the Flash LED in order to adequately couple the heat from the LED into the thermistor. ...
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Layout Recommendations The high frequency and large switching currents of the LM3554 make the choice of layout important. The following steps should be used as a reference to ensure the device is stable and maintains proper voltage and current regulation ...
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Physical Dimensions inches (millimeters) unless otherwise noted For Ordering, Refer to Ordering Information Table X1 = 1.695mm (±0.03mm 1.695mm (±0.03mm 0.6mm(±0.075mm) 16 Bump µSMD (0.4mm pitch) NS Package Number TMD16CCA 39 www.national.com ...
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