Application Note
Please read the Important Notice and Warnings at the end of this document
V 1.0
www.infineon.com/ref-ild8150-dc-1.5a
page 1 of 28
2019-01-18
AN_1809_PL39_1810_124440
ILD8150 80 V high side buck LED driver IC with
hybrid dimming
Operation, design guide and performance
About this document
Scope and purpose
This application note introduces Infineon’s hysteretic high-side MOSFET buck DC-DC LED driver IC ILD8150 for
general lighting applications. It describes the device operation, features and component value calculations and
selection. An example of the reference design performance is shown. ILD8150 provides a highly efficient
solution up to 97 percent with superior hybrid dimming performance, and various protections such as cycle-by-
cycle current limitation and over-temperature protection.
Intended audience
This document is intended for engineers and students who design highly efficient LED drivers with a wide
dimming range.
Table of contents
About this document ....................................................................................................................... 1
Table of contents ............................................................................................................................ 1
1
Introduction ............................................................................................................................. 3
1.1
Features .............................................................................................................................................................. 3
1.2
Applications ........................................................................................................................................................ 3
2
Circuit description ..................................................................................................................... 4
2.1
Operation ............................................................................................................................................................ 4
2.1.1
Current regulation ........................................................................................................................................... 4
2.2
Cycle-by-cycle current limitation ....................................................................................................................... 5
2.2.1
OTP
5
2.2.2
UVLO 5
2.2.3
Dimming ........................................................................................................................................................... 6
2.2.4
Dim-to-off ......................................................................................................................................................... 7
2.2.5
Soft-start .......................................................................................................................................................... 7
2.2.6
Shut-down ....................................................................................................................................................... 8
2.2.7
Floating driver and bootstrap supplying ........................................................................................................ 8
2.2.8
V
IN
pin ESD protection ...................................................................................................................................... 8
2.2.9
OVP by CS pin ................................................................................................................................................... 9
2.2.10
Microcontroller use........................................................................................................................................ 9
2.3
Component selection ....................................................................................................................................... 10
2.3.1
Current Sense (CS) resistor ........................................................................................................................... 10
2.3.2
Inductor and switching frequency selection ................................................................................................ 10
2.3.3
Diode D selection ........................................................................................................................................... 10
2.3.4
Input capacitor C
IN
selection ......................................................................................................................... 11
