ADT7110 ADTech, ADT7110 Datasheet - Page 7

• Manufacturer Part Number: ADT7110
• Description: fixed frequency step-down converter
• Manufacturer: ADTech

ADT7110
Application Hints (continued)
Example : typical application circuit
N = 6 (6 LED branches)
V
= 12V , V
= 9V
IN
OUT
ICC = 280mA (measured) , and efficiency is 80%.
So, calculated 1 branch LED current is 49.77mA.
▶ Dimming control
The LED brightness control can be obtained by forcing a
pulse wave to the EN input terminal. Typically, a 100Hz to
1kHz pulse signal is used. LED brightness is proportional to
the duty of pulse wave. And in this case , LED branch current
is RMS value of the PWM modulated current.
When the pulse-width is below 50% duty, the driving current
of ADT7110 can be increased up to current limit
condition.(~550mA) But you keep carefully to select the
inductor (L1) over 700mA rated current.
Note that the inductor (L1) is 590mA rated in typical
application circuit.
* This specifications are subject to be changed without notice
http://www.ad-tech.co.kr
Jun. 07. 2008 / Rev. 0.1
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