Help needed: Arc-LSH regulator IC

[djpark]

I tried search but couldn't find info.

Does anyone know what regulator IC is used in Arc LSH? I am hoping to try a uP to PWM the output.

TIA

-- dj

 

[cosco]

LT1618 from Linear Technology

 

[djpark]

Thanks!

 

[djpark]

[ QUOTE ]
cosco said:
LT1618 from Linear Technology

[/ QUOTE ]

I have been thinking of using PWM to control the SHDN (pin9) for brightness control. But the 1618 datasheet recommends using PWM with RC to control the current sending voltage to Iadj (pin4) for brightness control.

Which is better way in terms of power efficiency and visual result? PWM to SHDN to control the ON time (duty cycle) at max current, or lower constant current to led using Iadj?

-- dj