LM3528TMX National Semiconductor, LM3528TMX Datasheet
LM3528TMX
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LM3528TMX Summary of contents
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... HWEN/PGEN/GPIO for indicator LED flashing or for external logic control. The LM3528 is offered in a tiny 12-bump µSMD package and operates over the -40°C to +85°C temperature range. Typical Application Circuit © 2008 National Semiconductor Corporation Features ■ 128 Exponential Dimming Steps ■ ...
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... Connection Diagram Ordering Information Order Number Package Type LM3528TME 12-Bump µSMD LM3528TMX 12-Bump µSMD Pin Descriptions/Functions Pin Name A1 OVP Over-Voltage Protection Sense Connection. Connect OVP to the positive terminal of the output capacitor. A2 MAIN Main Current Sink Input. A3 SUB/FB Secondary Current Sink Input or 1.21V Feedback Connection for Constant Voltage Output. ...
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... Junction to Ambient Thermal -65°C to +150°C Resistance (θ ESD Caution Notice +300°C National Semiconductor recommends that all integrated cir- 2.5kV cuits be handled with appropriate ESD precautions. Failure to observe proper ESD handling techniques can result in dam- age to the device. = 25°C and those in boldface type apply over the Operating Temperature Range ...
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... For guaranteed specifications and test conditions, see the Electrical Characteristics. Note 2: All voltages are with respect to the potential at the GND pin. Note 3: For detailed soldering specifications and information, please refer to National Semiconductor Application Note 1112: Micro SMD Wafer LEvel Chip Scale Package (AN-1112). ...
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Timing Diagram FIGURE Timing 5 30020503 www.national.com ...
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Typical Performance Characteristics Mode 2.2µF (OLED Mode), C OUT +25°C unless otherwise specified. SUB MAIN A 2x6 LED Efficiency Strings of 6LEDs) 2x4 LED Efficiency Strings ...
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LED Efficiency vs I LED (2 Strings of 2LEDs) 30020512 18V OLED Efficiency vs I OUT 30020514 LED Efficiency TDK VLF3012AT-100MR92 40mA) 12V OLED Efficiency 0.36Ω ...
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LED Line Regulation (UNI = '0') OLED Line Regulation I = 60mA OLED www.national.com OLED Line Regulation I OLED 30020516 OLED Load Regulation V OLED 30020518 8 = 60mA 30020517 = 18V 30020519 ...
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OLED Load Regulation V = 12V OLED 30020520 Over Voltage Limit vs 30020522 Peak Current Limit vs. V Switch On-Resistance vs 30020521 IN 30020523 www.national.com ...
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Switching Frequency vs. V Shutdown Current vs. V www.national.com Maximum Duty Cycle vs 30020524 Switching Supply Current vs 30020526 10 IN 30020525 IN 30020527 ...
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LED Current Matching vs. CODE (Note 11) (UNI = '1 12kΩ -40°C to +85°C) SET A LED Current vs CODE ( 12kΩ±0.05%) MAIN SUB IDEAL SET LED Current Accuracy ...
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Start-Up Waveform (LED Mode) (2 × 5 LEDs, 20mA per string) Channel 2: SDA (5V/div) Channel 1: V (10V/div) OUT Channel 3: I (20mA/div) LED Channel 4: I (200mA/div) IN Time Base: 400µs/div Load Step (OLED Mode 18V, ...
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Line Step (OLED Mode 18V 2.2µF, V OUT OUT IN Channel 2: VOUT (AC Coupled, 100mV/div) Channel 3: VIN (AC Coupled, 500mV/div) Time Base: 200µs/div GPIO1 Functionality (GPIO1 Configured as OUTPUT, f Channel 2: GPIO (2V/div) ...
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Block Diagram Operation Description The LM3528 Current Mode PWM boost converter operates from a 2.7V to 5.5V input and provides two regulated outputs for White LED and OLED display biasing. The first output, MAIN, provides a constant current of up ...
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FB room at the input to the current sinks for proper current regulation. In the instance when there are unequal numbers of LEDs or unequal currents from string to string, the ...
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Figures 12 - 15). Figure 16 details an example bit pat- tern at a specific programmed duty cycle and frequency. A ‘1’ written to the PGEN_ registers forces HWEN/PGEN/GPIO low. A ‘0’ causes HWEN/PGEN/GPIO to go open ...
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COMPATIBLE INTERFACE The LM3528 is controlled via compatible interface. START and STOP conditions classify the beginning and the end of the session. A START condition is defined as SDA transitioning ...
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REGISTER DESCRIPTIONS There are 4, 8 bit registers within the LM3528 as detailed in Table 1. TABLE 1. LM3528 Register Descriptions Register Name General Purpose (GP) Brightness Main (BMAIN) Brightness Sub (BSUB) HWEN/PGEN/GPIO Control (HPG) General Purpose I/O Control (GPIO) ...
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TABLE 3. Operational Truth Table UNI OLED ENM ENM ,ENS, or OLED high enables analog ...
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TABLE 4. I vs. Brightness Register Data LED BMAIN BMAIN or BSUB I BSUB LED_MAX Brightness Brightness Data Data 0000000 0.000% 0100000 0000001 0.166% 0100001 0000010 0.175% 0100010 0000011 0.184% 0100011 0000100 0.194% 0100100 0000101 0.204% 0100101 ...
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FIGURE 9. I 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 ...
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TABLE 6. HPG Register Function Bits 7 – 6 Bits (PGEN Bit 2 (GPIO (PGEN Bit Enable/Disable Period) and Duty Cycle Selection 1.6µs/ 001 = 100% X bit (625kHz) 010 = 1/2 ...
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GPIO Register Function Bits GPIO Data Data (Bit 1) Direction (Bit Figures 12 – 15 detail the Pattern Generator Data Registers. These hold the 32 bit data that is output ...
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Figure 16 shows a write sequence to the pattern generator programmed to output the waveform in Figure 17. In this ex- ample HPG register bits <7:6> (for 26ms/bit) and bits <5:3> = 010 (for 1/2 duty cycle). The ...
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FIGURE 16. Pattern Generation Write Sequence SHUTDOWN AND OUTPUT ISOLATION The LM3528 provides a true shutdown for either MAIN or SUB/FB when configured as a White LED bias supply. Write ENM (bit 1) of the General Purpose ...
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Application Information LED CURRENT SETTING/MAXIMUM LED CURRENT Connect a resistor (R ) from SET to GND to program the SET maximum LED current (I ) into MAIN or SUB/FB. The LED_MAX relationship is: SET LED_MAX where SET ...
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TABLE 7. Recommended Output Capacitors Manufacturer Part Number TDK C1608X5R1E105M Murata GRM39X5R105K25D539 TDK C2012X5R1E225M Murata GRM219R61E225KA12 INDUCTOR SELECTION The LM3528 is designed for use with a 10µH inductor, how- ever 22µH are suitable providing the output capacitor is in- creased ...
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TABLE 9. Recommended Schottky Diodes Manufacturer Part Number On Semiconductor NSR0230P2T5G On Semicondcuctor NSR0230M2T5G On Semiconductor RB521S30T1 Diodes Inc. SDM20U30 Diodes Inc. B05030WS Philips BAT760 OUTPUT CURRENT RANGE (OLED MODE) The maximum output current the LM3528 can deliver in OLED ...
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APPLICATION CIRCUITS FIGURE 19. LED Backlight + OLED Power Supply LAYOUT CONSIDERATIONS Refer to AN-1112 for µSMD package soldering The high switching frequencies and large peak currents in the LM3528 make the PCB layout a critical part of the design. ...
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Physical Dimensions X1 = 1.215mm (±0.1mm 1.615mm (±0.1mm 0.6mm www.national.com inches (millimeters) unless otherwise noted 12 Bump µSMD For Ordering, Refer to Ordering Information Table NS Package Number TMD12 30 ...
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Notes 31 www.national.com ...
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