ADT6780 ADTECH [ADTech], ADT6780 Datasheet
ADT6780
Related parts for ADT6780
ADT6780 Summary of contents
Page 1
... Step-Down LED Driver FB General Description The ADT6780 is a thermally enhanced current mode step down LED driver. That is designed to deliver constant current to high power LEDs. The device is suitable for various high power LED application due to the wide operating range(VIN 4.5V~28V) and high output capability(continuous 2A) ...
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... Jul. 12. 2012 / Preliminary Step-Down LED Driver FB Type Value (Model) ADT6780 B230A 6.8uH / 3A 10㎌ / 35V 10㎌ / 10V 8.2㎋ 100㎋ 10㎋ 0.2Ω 2㏀ Description COMP 2/13 ADT6780 Manufacturer ADTech DIODES TDK - - - - - - - ADT6780 Package outline http://www.ad-tech.co.kr ...
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... Figure 2. Functional Block Diagram Symbol Min -0.3 BST -0 Θ -65 STG T - J.MAX Symbol Min 0.2 OUT T -40 OPR 3/13 ADT6780 Current Sense + Amplifier BST Driver SW 3 Driver 4 GND Typ. Max. Unit - 0 2. ℃/W ...
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... G = ±10㎂ ΔI EA COMP Duty=50 0.15V, IO=1A MAX rising 100㎋ - 4/13 ADT6780 Unit Min. Typ. Max ㎂ - 0.7 - ㎃ 0.184 0.200 0.216 V - 750 - V/V - 750 - ㎂/ mΩ Ω - 0.1 10 ㎂ A/V - ...
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... VIN=24V 20mV/div I INDUCTOR 0.5A/div 0.6 0.7 0.8 0.9 1 Switching Frequency vs Die Temperature 1050 1000 950 900 850 800 750 60 80 100 120 4.0 3.5 3.0 2.5 2.0 1.5 1.0 5/13 ADT6780 Steady State Operation 1㎲/div -40 - Temperature (℃) Peak Current vs Duty Duty (%) http://www.ad-tech.co.kr 100 120 100 ...
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... V SW 10V/div V EN 5V/div V OUT 2V/div I LED 0.5A/div 40㎲/div Enable Turn-off (C4 open 10V/div V EN 5V/div V OUT 2V/div I LED 0.5A/div 40㎲/div LED Current vs PWM Dimming Duty (C4 open, PWM Frequency=500Hz) 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 PWM Dimming Duty (%) 6/13 ADT6780 60 80 100 http://www.ad-tech.co.kr ...
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... DETAILED DESCRIPTION Enable and Soft Start EN pin of the ADT6780 operates both chip enable and UVLO function. EN pin voltage under 800mV shuts down all the chip function except for pulling up EN pin. When the EN pin voltage exceeds 1.1V, the internal regulator will be enabled pin voltage over 2.7V, the soft start capacitor will begin to charge and enables all the operations including switching function ...
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... APPLICATION INFORMATION Figure 1 is the typical ADT6780 application circuit. And Figure 2 is the functional block diagram of the ADT6780. For the application information, refer to the Figure 1 & 2 unless otherwise noted. LED Current Resistor Selection The LED current is set with a current sense resistor R1 between FB and GND ...
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... F ⎝ SW ⎛ 1 ⎜ ⎜ = × ΔV ΔI OUT L × × ⎝ × ΔV ΔI ESR OUT L 9/13 ADT6780 ⎞ V ⎟ ⎟ OUT V ⎠ IN ⎞ V ⎟ ⎟ OUT V ⎠ IN ⎞ ⎟ ⎟ × C ⎠ O ⎞ ⎟ ⎟ ⎠ O http://www.ad-tech.co.kr ...
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... APPLICATION INFORMATION Loop Compensation The ADT6780 uses a fixed frequency, peak current mode control scheme to provide easy compensation and fast transient response. Peak current mode control eliminate the double pole effect of the output LC filter. Therefore, the step-down converter can be simplified one-pole system in frequency domain. ...
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... below 1/4 of the Fc to provides sufficient phase margin. C3 value ≥ C3 × × 2π then × C2 ESR = C6 R2 11/13 ADT6780 C6 ( ㎊ (uH ㎌ ) None 6 None ㎊ (uH ㎌ ) None 6 None http://www.ad-tech.co.kr ...
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... After the die temperature falls by 10°C typically, the device automatically restarts, using the soft-start sequence. The ADT6780 is available in a thermally enhanced SOP package and can dissipate up to 1.25W at Ta=50°C (T =125°C). The exposed pad should be connected to GND externally, preferably soldered to a large ground J plane to maximize thermal performance ...
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... ADT6780 Dimensions In Inches Min Max 0.053 0.069 0.004 0.010 0.053 0.061 0.013 0.020 0.006 0.010 0.185 0.200 0.126 0.134 0.150 0.157 0.228 ...