LM3509SDEV National Semiconductor, LM3509SDEV Datasheet
LM3509SDEV
Specifications of LM3509SDEV
Related parts for LM3509SDEV
LM3509SDEV Summary of contents
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... R_SDA, R_SCL, R_GPIO 10kΩ, CRCW06031002F D1 Schottky, 30V, 0.5A, B0530WS R1, R2 Unpopulated (used for Constant Voltage Ouptut) © 2007 National Semiconductor Corporation National Semiconductor Application Note 1594 Travis Eichhorn June 2007 a white LED + OLED bias supply the LM3509 can indepen- dently and simultaneously drive a string white LED’s and deliver a constant output voltage 21V for OLED panels ...
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FIGURE 2. LM3509 Evaluation Board Layout (Top Side) FIGURE 3. LM3509 Evaluation Board Layout (Bottom Side) www.national.com 2 30011102 30011103 ...
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... TERNAL CONTROL INTERFACE section of this document. External Control Interface There are two mothods for controlling the LM3509 Evaluation Board. The first option is via a National Semiconductor USB Interface Board. The second option is by using the SDA and SCL headers available on the upper right corner of the board. ...
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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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Table 2. General Purpose Register Bit Function Bit Name 0 ENM Enable MAIN. Writing this bit enables the main current sink (MAIN). Writing this bit disables the main current sink and forces MAIN high ...
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Brightness Registers (BMAIN and BSUB) With the UNI bit (General Purpose register) set to 0 (Non- Unison mode) both brightness registers (BMAIN and BSUB) independently control the LED currents I spectively. BMAIN and BSUB are both 8 bit, but with ...
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FIGURE 10 BMAIN or BSUB Data MAIN SUB 7 30011111 www.national.com ...
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Brightness Rate of Change Description RMP0 and RMP1 control the rate of change of the LED cur- rent I and I in response to changes in BMAIN and / MAIN SUB/FB or BSUB. There are 4 user programmable LED current ...
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LM3509 Compatible Interface Program In order to fully evaluate the LM3509 with the National Semi- conductor USB Interface Board, National has created an I compatible program (LM3509 .exe begin with, plug the LM3509 evaluation board ...
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Applications Information LED Current Setting/Maximum LED Current Resistor R connected from SET to GND sets the maximum SET LED current. The board is shipped with a 12.1kΩ for R giving a maximum LED current of 20mA/string. For higher or lower ...
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Notes 11 www.national.com ...
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