LTC3206 Linear Technology, LTC3206 Datasheet
LTC3206
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LTC3206 Summary of contents
Page 1
... LED current source begins to enter dropout. Internal circuitry prevents inrush current and excess input noise during start-up and mode switching. The LTC3206 is available in a 24-lead (4mm × 4mm) QFN package. SUB DISPLAY RGB ILLUMINATOR 2.2µ ...
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... MAIN-MAIN, MAIN-AUX, SUB-SUB, SUB-AUX 25µA < I < 75µA RGB RED, GREEN, BLUE Voltage = 1V 1.5x Mode Switch Threshold 20mA LED 4.2V (Note 3) IN CPO U W ORDER PART TOP VIEW NUMBER LTC3206EUF 1 18 BLUE 2 17 GREEN RED CPO 6 ...
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... Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: The LTC3206E is guaranteed to meet performance specifications from 0°C to 70°C. Specifications over the –40°C to 85°C operating temperature range are assured by design, characterization and correlation ...
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... LTC3206 W U TYPICAL PERFOR A CE CHARACTERISTICS 1x Mode Switch Resistance vs Temperature 0 100mA CPO 0 3. 3. 3.9V IN 0.6 0.5 –40 – TEMPERATURE (°C) 3206 G04 Oscillator Frequency vs Supply Voltage 1100 1000 T = 25° –40°C A 900 T = 85°C A 800 700 2.7 3.0 3.3 3.6 3.9 4.2 4.5 V SUPPLY VOLTAGE (V) IN ...
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... This pin sets the logic reference level of the CC SDA, SCL and ENRGB/S pins. 2 SDA (Pin 8): Input Data for the I C Serial Port. Serial data is shifted in one bit per clock to control the LTC3206 (see Figures 3 and 4). The logic level for SDA is referenced ...
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... LED with the largest forward voltage will reach the drop- out threshold first. When any of the LED pins reach the drop- IN out threshold, the LTC3206 will switch to boost mode and IN automatically soft-start the 1.5x boost charge pump. The constant frequency charge pump is designed to minimize the amount of noise generated at the V – ...
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... The 1.5x step-up charge pump uses a patented constant frequency architecture to combine the best efficiency with the maximum available power at the lowest noise level. The charge pump of the LTC3206 can be forced to come on even if no LEDs are programmed for current. Setting bit the I C serial port forces the charge pump on (see Figure 3) ...
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... This is equivalent to an 8-bit address where the least significant bit of the address is always 0. If the correct seven bit address is given but the R/W bit is 1, the LTC3206 will not respond. Bus Write Operation The master initiates communication with the LTC3206 with a START condition and a 7-bit address followed by the Write Bit R ...
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... DIAGRA LTC3206 3206f 9 ...
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... The power to the LED will be the product of the subrange (DC current) and the PWM setting. For example LED power of 2.25% is desired, then the LTC3206 sets the sub range to 25% and the duty cycle to 8.8%. These settings are designed to optimize the effi- ciency of the dual-mode LTC3206 power management system while preserving LED color accuracy at low power levels ...
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... R RGB V , CPO Capacitor Selection IN The style and value of capacitors used with the LTC3206 determine several important parameters such as regulator control-loop stability, output ripple and charge pump strength. To reduce noise and ripple recommended that low equivalent series resistance (ESR) multilayer ceramic capacitors be used on both V lum and aluminum capacitors are not recommended be- cause of their high ESR ...
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... Likewise, excessive ESR on the output capacitor will tend to degrade the loop stability of the LTC3206. The closed-loop output resis- tance of the LTC3206 is designed to be 0.4Ω. For a 100mA load current change, the error signal will change by about 40mV. If the output capacitor has 0.4Ω or more of ESR, ...
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... The large dv/dt on these pins can couple energy capacitively to adjacent printed circuit board runs. Magnetic fields can also be generated if the flying capacitors are not close to the LTC3206 (i.e., the loop area is large). To decouple capacitive energy transfer, a Faraday shield may be used. This is a grounded PC trace between the sensitive node and the LTC3206 pins ...
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... LTC3206 U U APPLICATIO S I FOR ATIO Once an LED pin drops out, the LTC3206 switches into step-up mode. Employing the fractional ratio 1.5x charge pump, the LTC3206 provides more efficiency than would be achieved with a voltage doubling charge pump. In 1.5x boost mode, the efficiency is similar to that of a linear regulator with an effective input voltage of 1 ...
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... DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE, IF PRESENT 4. EXPOSED PAD SHALL BE SOLDER PLATED 5. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE 6. DRAWING NOT TO SCALE LTC3206 CAMERA ILLUMINATOR LIGHT 2.2µF RED ...
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... ThinSOT is a trademark of Linear Technology Corporation. Linear Technology Corporation 16 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● 5-LED Main Plus Low/High Current Camera Light 2.2µF 2.2µF MAIN DISPLAY V CPO IN LTC3206 4 MAIN1-4 AUX 1 AUX 2 3 ENRGB/S TORCH MODE SUB1-2 FLASH MODE 3 SERIAL PORT RGB I ...