General Description
The MAX20090 is a single-channel high-brightness LED
(HB LED) driver for automotive front-light applications such
as high beam, low beam, daytime running lights (DRLs),
turn indicators, fog lights, and other LED lights. It can take
an input voltage from 5V to 65V and drive a string of LEDs
with a maximum output voltage of 65V.
The device senses output current at the high side of the
LED string. High-side current sensing is required to pro-
tect for shorts from the output to the ground or battery
input. It is also the most flexible scheme for driving LEDs,
allowing boost, high-side buck, SEPIC mode, or buck-
boost-mode configurations. The PWM input provides LED
dimming ratios of up to 1000:1, and the ICTRL input provides
additional analog dimming capability in the controller. The
device also includes a fault flag (FLT) that indicates open
string, shorted string, and thermal shutdown. The device
has built-in spread-spectrum modulation for improved
electromagnetic-compatibility performance. The device
can also be used in zeta and Cuk converter configura-
tions, if necessary in some applications. The MAX20090 is
available in a space-saving (4mm x 4mm), 20-pin TQFN,
20-pin side-wettable TQFN, or a 20-pin TSSOP pack-
age and is specified to operate over the -40°C to +125°C
automotive temperature range
Applications
● Automotive Exterior Lighting
● High-Beam/Low-Beam/Signal/Position Lights
● Daytime Running Lights (DRLs)
● Fog Lights and Adaptive Front-Light Assemblies
● Head-Up Displays
● Commercial, Industrial, and Architectural Lighting
Benets and Features
● High-Brightness LED Driver with a Wide Input Range
Saves Space and Cost Through Integration
• +5V to +65V Wide Input Voltage Range
• +65V Maximum Boost Output Voltage
• ICTRL Pin for Analog Dimming
• Integrated High-Side Current-Sense Amplier
• 200Hz On-Board Ramp Simplies PWM Dimming
● Flexible Architecture Enables Easy Design
Optimization
• Congurable as Boost, High-Side Buck, SEPIC,
Buck-Boost, Zeta, and Cuk
• Programmable Switching Frequency (200kHz to
2.2MHz)
• Spread-Spectrum Modulation to Reduce EMI Noise
● Automotive Features and Robustness Improve
System Reliability
• Fault Diagnosis Through Fault Flag
• Short Circuit, Overvoltage, and Thermal Protection
• -40°C to +125°C Operating Temperature Range
Ordering Information appears at end of data sheet.
19-8747; Rev 0; 12/16
IN
PWMDIM
RT
V7V
SGND
ICTRL
NDRV
CS
OVP
ISENSE+
ISENSE-
FLT
COMP
DIMOUT
PGND
EP
L1
N1
C
IN
PWMDIM
P1
BST
V
CC
UVEN
R3
R
RT
R4
C2
C1
C
COMP
R
COMP
INPUT
D1
R
CS_FET
100Ω
R
SC
C
BST
C
OUT
R
OVP1
R
OVP2
R
CS_LED
ANALOG DIM
MAX20090
Simplied Typical Operating Circuit
MAX20090 Automotive High-Voltage HB LED Controller
