LP55281RLEV National Semiconductor, LP55281RLEV Datasheet
LP55281RLEV
Specifications of LP55281RLEV
Related parts for LP55281RLEV
LP55281RLEV Summary of contents
Page 1
... LP55281 has also a LED test feature, which can be used for example in production for checking the LED connections. Figure 1. LP55281 Evaluation Board With USB Interface Board © 2007 National Semiconductor Corporation National Semiconductor AN-1631 Sami Kotijarvi ...
Page 2
Evaluation Software LP55281 evaluation software and some support files are sup- plied on the delivery CD together with all available documen- tation regarding the circuit. You can copy the software and the files to your PC’s hard disk. The program ...
Page 3
COMMON TAB The Common Tab contains evaluation board control func- tions. Automatic writing (Update registers immediately) is enabled by default. It means that a write operation is done after every mouse click. If you want to change several settings in ...
Page 4
BOOST TAB Boost is enabled in this tab by checking the boost enable. The internal active load can be enabled to eliminate pulse skipping of the boost converter. Active load will consume some power when the boost output current is ...
Page 5
COLOR LEDS TAB For each RGB LED, there is its own subtab in the Color LEDs tab. In each subtab (RGB1-4) you can enable the RGB, set its PWM with the slider and select its current from the drop- down ...
Page 6
LED TEST, ALED AND AUDIO SYNCHRONIZATION TAB In this tab LED test, ALED and Audio Sync. is controlled. LED test can be done automatically with LED Auto Test by pushing Start button. Test will go thru all the leds and ...
Page 7
LED TEST TAB In LED test tab all the LEDs are tested with one press of a button. You can set Boost voltage, RGB 1-4 currents and ALED current. After pressing Start, test program automati- cally tests all the LEDs ...
Page 8
HISTORY TAB The History Tab records the command sequence of your ses- sion. You can copy-paste this information to another applica- tion if you wish. www.national.com Figure 8. History Tab 8 30019506 ...
Page 9
Evaluation Hardware The evaluation board has the LP55281 circuit with the nec- essary external components placed around it. Test points for the circuit pins are on the board edges. LEDs are on the right and left side of the board ...
Page 10
USB Interface The USB interface forms the connection between the PC and the evaluation system. It converts the commands from SPI format. It also provides adjustable supply voltage for the evaluation board and makes ...
Page 11
Getting Started The following instructions show how to use the LP55281 eval- uation kit in default conditions with the USB interface board. Please use the ESD protection (ground cable) to prevent any unwanted damaging ESD events. 1. Check the jumpers ...
Page 12
Schematics of The Evaluation Board www.national.com 12 ...
Page 13
List of Main Components Part Number QTY L1 1 D8-D11 C5 Value, Size, Description Tolerance 4.7 µH Power Inductor RGB 3-Color LEDs Zener Diode Schottky Barrier Diode Philips BAT760-SOD323 10 µF, 0805, 10% ...
Page 14
... National Semiconductor and the National Semiconductor logo are registered trademarks of National Semiconductor Corporation. All other brand or product names may be trademarks or registered trademarks of their respective holders. ...