lt3498eddb-trpbf Linear Technology Corporation, lt3498eddb-trpbf Datasheet
lt3498eddb-trpbf
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lt3498eddb-trpbf Summary of contents
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... The off time of the switch is not allowed to exceed a fi xed level, guaranteeing a switching frequency that stays above the audio band. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. *Patent Pending 4 ...
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... PACKAGE/ORDER INFORMATION EXPOSED PAD (PIN 13) IS GND, MUST BE SOLDERED TO PCB ORDER PART NUMBER LT3498EDDB Order Options Tape and Reel: Add #TR Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF Lead Free Part Marking: Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T PARAMETER Switch Leakage Current CAP1 Pin Overvoltage Protection Schottky Forward Voltage Schottky Reverse Leakage OLED Driver Feedback Voltage Feedback Resistor Minimum Switch Off Time Minimum Switch Off Time Maximum Switch ...
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LT3498 TYPICAL PERFORMANCE CHARACTERISTICS Shutdown Current ( 0V) CTRL1 CTRL2 – 125 (V) IN ...
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TYPICAL PERFORMANCE CHARACTERISTICS LED Switching Frequency vs Temperature 2.6 2.5 2.4 2.3 2.2 2.1 2.0 1.9 1.8 – 50 – 100 TEMPERATURE ( C) 3498 G10 OUT2 CTRL2 (V = 16V) OUT2 ...
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LT3498 TYPICAL PERFORMANCE CHARACTERISTICS LED Switching Waveforms V SW 10V/DIV V CAP1 50mV/DIV I L 100mA/ DIV 3498 G19 500ns/DIV V = 3.6V IN FRONT PAGE APPLICATION OLED Switching Waveforms with 4mA Load V OUT2 10mV/DIV AC COUPLED SW2 VOLTAGE ...
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PIN FUNCTIONS V (Pin 7): Drain of Output Disconnect PMOS. OUT2 Place a bypass capacitor from this pin to GND. See the Applications Information section. CAP2 (Pin 8): Output of the OLED Driver. This pin is connected to the cathode ...
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LT3498 OPERATION—LED DRIVER The LED portion of the LT3498 uses a constant-frequency, current mode control scheme to provide excellent line and load regulation. Operation can be best understood by referring to the Block Diagram. At power-up, the capacitor at the ...
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OPERATION—OLED DRIVER The low noise boost of the LT3498 uses a novel control scheme to provide high effi ciency over a wide range of output current. In addition, this technique keeps the switching frequency above the audio band over all ...
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LT3498 APPLICATIONS INFORMATION—LED DRIVER Table 2: Recommended Ceramic Capacitor Manufacturers Taiyo Yuden (800) 368-2496 www.t-yuden.com AVX (803) 448-9411 www.avxcorp.com Murata (714) 852-2001 www.murata.com Overvoltage Protection The LED driver of the LT3498 has an internal open-circuit protection circuit. In the cases ...
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APPLICATIONS INFORMATION— LED DRIVER Programming LED Current The feedback resistor (R ) and the sense voltage SENSE1 (V – control the LED current. The CTRL1 pin CAP1 LED1 controls the sense reference voltage as shown in the Typical ...
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LT3498 APPLICATIONS INFORMATION—LED DRIVER Direct PWM Dimming Changing the forward current fl owing in the LEDs not only changes the intensity of the LEDs, it also changes the color. The chromaticity of the LEDs changes with the change in forward ...
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APPLICATIONS INFORMATION— LED DRIVER The time it takes for the LED current to reach its pro- grammed value sets the achievable dimming range for a given PWM frequency. For example, the settling time of the LED current in Figure 6 ...
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LT3498 APPLICATIONS INFORMATION—OLED DRIVER Inductor Selection Several recommended inductors that work well with the OLED driver of the LT3498 are listed in Table 5, although there are many other manufacturers and devices that can be used. Consult each manufacturer for ...
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APPLICATIONS INFORMATION— OLED DRIVER a soft transition occurs between the CTRL2 pin and the internal reference. Figure 10 shows this behavior. 1.500 1.250 1.000 0.750 0.500 0.250 0 0 0.5 0.8 1.0 0.3 CTRL2 VOLTAGE (V) Figure 10. CTRL2 to ...
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LT3498 APPLICATIONS INFORMATION—OLED DRIVER Maximum Output Load Current The maximum output current of a particular LT3498 circuit is a function of several circuit variables. The fol- lowing method can be helpful in predicting the maximum load current for a given ...
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APPLICATIONS INFORMATION— LED AND OLED DRIVER Board Layout Considerations As with all switching regulators, careful attention must be paid to the PCB board layout and component placement. To prevent electromagnetic interference (EMI) problems, proper layout of high frequency switching paths ...
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LT3498 TYPICAL APPLICATIONS 20mA C , C2: X5R OR X7R WITH SUFFICIENT VOLTAGE RATING IN C1: TAIYO YUDEN GMK212BJ105KG C3: TAIYO YUDEN TMK316BJ106ML L1, L2: MURATA LQH32CN100K53 18 Li-Ion to Two White LEDs and OLED/LCD Bias ...
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TYPICAL APPLICATIONS C2: X5R OR X7R WITH SUFFICIENT VOLTAGE RATING IN C1: TAIYO YUDEN GMK212BJ105KG C3: TAIYO YUDEN TMK316BJ106ML L1, L2: MURATA LQH32CN100K53 Li-Ion to Two White LEDs and OLED/LCD Bias ...
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LT3498 TYPICAL APPLICATIONS C2: X5R OR X7R WITH SUFFICIENT VOLTAGE RATING IN C1: TAIYO YUDEN GMK212BJ105KG C3: TAIYO YUDEN TMK316BJ106ML L1: MURATA LQH32CN150K53 L2: MURATA LQH32CN100K53 20 Li-Ion to Three White LEDs and OLED/LCD Bias ...
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TYPICAL APPLICATIONS C2: X5R OR X7R WITH SUFFICIENT VOLTAGE RATING IN C1: TAIYO YUDEN GMK212BJ105KG C3: TAIYO YUDEN TMK316BJ106ML L1: MURATA LQH32CN150K53 L2: MURATA LQH32CN100K53 Li-Ion to Four White LEDs and OLED/LCD Bias V = ...
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LT3498 TYPICAL APPLICATIONS C2: X5R OR X7R WITH SUFFICIENT VOLTAGE RATING IN C1: TAIYO YUDEN GMK212BJ105KG C3: TAIYO YUDEN TMK316BJ106ML D1: CENTRAL SEMICONDUCTOR CMDSH-3 L1: MURATA LQH32CN150K53 L2: MURATA LQH32CN100K53 LED Effi ciency ...
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... SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... Schottky Diode and 250:1 True Color PWM LT3591 Constant-Current, 1MHz, High Effi ciency White LED Boost Regulator with Integrated Schottky Diode and 80:1 True Color PWM Dimming ThinSot and True Color PWM are trademarks of Linear Technology Corporation Linear Technology Corporation 24 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● ...