Analog Devices, Inc. (ADI) today announced the LT3964 Power by Linear, a dual, 36V, high efficiency, synchronous, step-down LED driver with an internal 40V, 1.6A power switch And I2C interface to simplify LED dimming control.
The LT3964 operates with fixed-frequency, current-mode control and operates as a constant-current and constant-voltage source with accurate current regulation to provide optimal LED lighting in automotive, industrial and architectural lighting applications. The two channels synchronize at full current load Operation can produce efficiencies above 94%.
The device's 400kHz I2C interface greatly simplifies digital PWM dimming by eliminating the need to provide a PWM signal from the microcontroller to the LED driver. Instead, it sets the internal register through the desired dimming duty cycle that can be synchronized to Internal Clocking. The device provides dimming rates up to 8192: 1 and excludes beat frequencies caused by the PWM signal and the internal oscillator being out of sync or, in analog dimming, via the 8-bit settable via I2C The scaling factor that sets the ratio of the control voltage to the LED current allows for more control over analog dimming regulation. The device also offers 1000: 1 external PWM dimming and 10: 1 analog dimming.
The switching frequency of the LT3964 can be set from 200kHz to 2MHz or can be synchronized to an external clock signal. The LED driver protection features include open and short LED fault detection, LED overcurrent and overvoltage detection, all Reportable via I2C interface. Thermal shutdown and provides an additional layer of protection.
The LT3964EUHE is available in a thermally enhanced 36-pin 5mm x 6mm QFN package Available in 3 temperature versions: Extended and Industrial Temperature versions Operates over the -40 ° C to 125 ° C (junction temperature), high temperature version Operating at -40 ° C to 150 ° C.