cat3649 ON Semiconductor, cat3649 Datasheet
cat3649
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cat3649 Summary of contents
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... PWM signal frequency up to 200 kHz. The CAT3649 can be shut down by holding the ADIM or PWM input in a logic low condition for greater than 30 ms. ON Semiconductor’s Quad−Mode 1.33x charge pump switching architecture is patented ...
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Table 1. ABSOLUTE MAXIMUM RATINGS VIN, LEDx, C1±, C2±, PWM, ADIM, CPWM voltage VOUT Storage Temperature Range Junction Temperature Range Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the Recommended Operating ...
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Figure 2. ADIM Dimming Timing Diagram (no C Table 4. ELECTRICAL OPERATING CHARACTERISTICS Parameter Quiescent Current (excluding load) Shutdown Current LED Current Setting LED Current Accuracy LED Channel Matching CPWM Pin Regulated Voltage Output Resistance (open loop) Charge Pump Frequency ...
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... Basic Operation At power−up, the CAT3649 starts operating in 1x mode where the output will be approximately equal to the input supply voltage (less any internal voltage losses). If the output voltage is sufficient to regulate all LED currents, the device remains in 1x operating mode. If the input voltage is insufficient or falls to a level where the regulated currents cannot be maintained, the device automatically switches into 1 ...
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TYPICAL PERFORMANCE CHARACTERISTICS (V = 3.6 V, PWM = OUT 3 1.33x 5.0 4.5 4.0 3.5 INPUT VOLTAGE (V) Figure 4. Quiescent Current vs. Input ...
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TYPICAL PERFORMANCE CHARACTERISTICS (V = 3.6 V, PWM = OUT 100 1.33x 3. LED ...
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TYPICAL PERFORMANCE CHARACTERISTICS (V = 3.6 V, PWM = OUT 2.0 1 0.4 0 2.5 3.0 3.5 4.0 4.5 INPUT VOLTAGE (V) Figure 16. ADIM, PWM V HI Figure ...
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TYPICAL PERFORMANCE CHARACTERISTICS (V = 3.6 V, PWM = OUT 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0 100 150 200 LOAD CURRENT (mA) Figure 22. Foldback Current Limit Figure 24. Dimming ...
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... TAB is the exposed pad underneath the package. For best thermal performance, the tab should be soldered to the PCB and connected to the ground plane. CPWM is the pin for connecting an external capacitor used to filter the PWM signal inside the CAT3649. http://onsemi.com 9 ...
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Current Selection After power−up and once enabled, the LED current is set initially to the full scale of 25 mA. The number of pulses (n) on the ADIM input decreases the current value as follows LED current ...
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Figure 28. ADIM Dimming Timing Diagram ( Filtering Capacitor PWM The PWM input signal controls the LED current proportionally to its duty cycle. When the LED driver operates in PWM dimming mode, the C minimizes the LED current ...
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... For applications with five LEDs or less required to tie the unused LED pin(s) directly to VOUT (see Figure 30 2 C1+ C1− C2+ C2− 5.5 V VOUT VIN CIN VIN CAT3649 1 mF LED1 LED2 ADIM LED3 PWM LED4 CPWM LED5 CPWM GND LED6 47 nF Figure 30. Application with 5 LEDs ...
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D PIN#1 INDEX AREA TOP VIEW SYMBOL MIN NOM A 0.70 0.75 A1 0.00 0.02 A3 0.20 REF b 0.18 0.25 D 2.90 3.00 D2 1.40 −−− E 2.90 3.00 E2 1.40 −−− e 0.50 BSC L 0.30 0.40 Notes: ...
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... All packages are RoHS−compliant (Lead−free, Halogen−free). 5. The standard lead finish is NiPdAu. 6. The device used in the above example is a CAT3649HV3−GT2 (TQFN, NiPdAu, Tape & Reel, 2,000/Reel). 7. For additional package and temperature options, please contact your nearest ON Semiconductor Sales office. ...