120V AC input and 24.5V output LED Driver


Design files


It is an offline AC-DC LED driver. It has TRIAC dimming capability. It is basically a low side buck which has valley filled PFC. It takes an input voltage of 120V AC. This circuit uses LM3445 which is an adaptive constant off-time AC/DC buck (step-down) constant current controller designed to be compatible with Traic dimmers.

Output voltage options PMP7770.1
Vin (Min) (V) 120
Vin (Max) (V) 120
Vout (Nom) (V) 24.5
Iout (Max) (A) 1
Output Power (W) 24.5
Isolated/Non-Isolated Non-Isolated
Input Type AC
Topology Buck- PFC

Design files & products

Design files

Download ready-to-use system files to speed your design process.

SNVU022.PDF (904 K)

Test results for the reference design, including efficiency graphs, test prerequisites and more

SNVR039.PDF (169 K)

Detailed schematic diagram for design layout and components

SNVR040.PDF (96 K)

Complete listing of design components, reference designators, and manufacturers/part numbers


Includes TI products in the design and potential alternatives.

Illumination LED drivers

LM3445Triac dimmable offline LED driver

Data sheet document-pdfAcrobat PDF open-in-new HTML

Technical documentation

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Type Title Date
Test report PMP7770 Test Result Jan. 09, 2012

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