LP55281RLEV National Semiconductor, LP55281RLEV Datasheet

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... LP55281 has also a LED test feature, which can be used for example in production for checking the LED connections. Typical Application National Semiconductor ® registered trademark of National Semiconductor Corporation. © 2007 National Semiconductor Corporation Features ■ Audio synchronization for a single fun light LED ■ ...

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Connection Diagram 36-bump Micro SMD package 0.6 mm body size, 0.5 mm pitch NS Package Number TLA36AAA 36-bump Micro SMDxt package 0.65 mm body size, 0.5 mm pitch NS Package Number RLA36AAA ...

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Pin Descriptions Pin Name GND_SW SS/SDA Logic Input/Output 5B IRGB 5A GND_RGB1 4F GND_RGB2 4E GND 4D ASE2 4C SI/A0 Logic Input ...

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Block Diagram www.national.com 4 20201174 ...

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... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. V (SW, FB, R1-4, G1-4, B1-4, ALED (Notes 3, 4 DD1 DD2 DDIO DDA Voltage on ASE1-2, IRT, -0. IRGB, VREF Voltage on Logic Pins -0. (all other pins): Voltage to ...

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V Output voltage of (Note 12) DDA internal LDO for analog parts MAGNETIC BOOST DC/DC CONVERTER ELECTRICAL CHARACTERISTICS Symbol Parameter Condition I Recommended 3.0V LOAD Load Current V OUT 3.0V V OUT V Output Voltage 3.0V OUT Accuracy (FB pin) ...

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... Note 5: Internal thermal shutdown circuitry protects the device from permanent damage. Thermal shutdown engages 140°C (typ.) Note 6: For detailed soldering specifications and information, please refer to National Semiconductor Application Note AN1112 : Micro SMD Wafer Level Chip Scale Package or National Semiconductor Application Note AN1412 : Micro SMDxt Wafer Level Chip Scale Package. ...

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Modes of Operation RESET: In the RESET mode all the internal registers are reset to the default values and the device goes to STANDBY mode after reset. NSTBY control bit is low after reset by default. Reset is entered always ...

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Magnetic Boost DC/DC Converter The LP55281 Boost DC/DC Converter generates a 4.0 - 5.3V supply voltage for the LEDs from single Li-Ion battery (3V... 4.5V). The output voltage is controlled with an 8-bit register in 9 steps. The converter is ...

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BOOST STANDBY MODE User can stop the Boost Converter operation by writing the Enables register bit EN_BOOST low. When EN_BOOST is written high, the converter starts for PFM mode and then goes to PWM mode. BOOST OUTPUT ...

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BOOST CONVERTER TYPICAL PERFORMANCE CHARACTERISTICS Boost Converter Efficiency Battery Current vs Voltage Boost Line Regulation Boost Typical Waveforms with 100 mA Load 20201198 20201109 Battery Current vs Voltage 20201111 Boost Startup with No Load 11 20201108 20201110 20201112 www.national.com ...

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Boost Load Regulation 100 mA Output Voltage vs Load Current www.national.com 20201113 20201115 Efficiency at Low Load vs Autoload 12 20201114 20201116 ...

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Functionality of RGB LED Outputs (R1-4, G1-4, B1-4) LP55281 has 4 sets of RGB/color LED outputs. Each set has 3 outputs, which can be controlled individually with a 6-bit PWM control register. The pulsed current level for each LED output ...

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RGB DRIVER TYPICAL PERFORMANCE CHARACTERISTICS Output Current vs Pin Voltage (Current Sink Mode) www.national.com 20201126 Output Current vs R (Current Sink Mode) 14 20201127 RGB ...

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Audio Synchronization The ALED output can be synchronized to incoming audio with Audio Synchronization feature. Audio Synch synchronizes ALED based on input signal's peak amplitude. Programmable gain and automatic gain control function are also available for adjustment of input signal ...

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ALED Driver LP55281 has a single ALED driver constant current sink with an 8-bit control. ALED driver can be used current sink or an audio synchronized current sink. Note, that when the audio synchronization ...

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LED TEST PROCEDURE An example of LED test sequence is presented here. Note, that user can use incremental write sequence on I consists of the basic setup and measurement phases for all RGB LEDs and Boost voltage. Basic setup phase ...

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Shielding To shield LP55281 from high input voltages (6 to 7.2V), the use of external 2.8V LDO is required. This 2.8V voltage protects internally the device against high voltage condition. The recommended connection is shown in the picture below. ...

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Control Interface The LP55281 supports two different interface modes: • SPI interface (4 wire, serial) • compatible (2 wire, serial) User can define the serial interface by IF_SEL pin. If IF_SEL = mode ...

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SPI Timing Parameters 2.8V DD DDIO Symbol Parameter 1 Cycle Time 2 Enable Lead Time 3 Enable Lag Time 4 Clock Low Time 5 Clock High Time 6 Data Setup Time 7 Data Hold Time 8 ...

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COMPATIBLE SERIAL BUS INTERFACE Interface Bus Overview The compatible synchronous serial interface provides ac- cess to the programmable functions and registers on the device. This protocol uses a two-wire interface for bidirec- tional communications ...

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SDA line is not pulled down. Addressing Transfer Formats Each device on the bus has a unique slave address. The LP55281 operates as a slave device ...

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When a READ function accomplished, a WRITE function must precede the READ function, as shown in the Read Cycle waveform. • write (SDA = 0) • read (SDA = 1) • ack = ...

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Recommended External Components OUTPUT CAPACITOR OUT The output capacitor C directly affects the magnitude of OUT the output ripple voltage. In general, the higher the value the lower the output ripple magnitude. Multilayer ce- OUT ...

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LP55281 Registers Following table summarizes the registers and their default values Address Register D7 00h RED1 R1 - IPLS[7:6] 0 01h GREEN1 G1 - IPLS[7:6] 0 02h BLUE1 B1 - IPLS[7:6] 0 03h RED2 R2 - IPLS[7:6] 0 04h GREEN2 ...

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... Micro SMDxt package 0.65 mm, 0.5 mm pitch See National Semiconductor Application Note AN–1112 Micro SMD Wafer Level Chip Scale Package for PCB design and assembly instructions for Micro SMD. For Micro SMDxt see National Semiconductor Application Note AN–1412 Micro SMDxt Wafer Level Chip Scale Package www ...

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