High Efficiency Buck Dual
LED Driver with Integrated
Current Sensing for
Automotive Front Lighting
NCV78723
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The NCV78723 is a single-chip and high efficient Buck Dual LED
Driver designed for automotive front lighting applications like high
beam, low beam, DRL (daytime running light), turn indicator, fog
light, static cornering, etc. The NCV78723 is in particular designed for
high current LEDs and provides a complete solution to drive 2 LED
24
1 24 1
strings of up-to 60 V. It includes 2 independent current regulators for
QFN24 QFNW24
the LED strings and required diagnostic features for automotive front
CASE 485CS CASE 484AF
lighting with a minimum of external components the chip doesnt
need any external sense resistor for the buck current regulation.
Theavailable output current and voltages can be customized per MARKING DIAGRAM
individual LED string. When more than 2 LED channels are required
on 1 module, then 2, 3 or more devices NCV78723 can be combined;
1
also with NCV78713 device the derivative of the NCV78723 ON
incorporating Buck Single LED Driver. Thanks to the SPI
N787230
programmability, one single hardware configuration can support
AWLYYWW
various application platforms.
Features
Single Chip
1
ON
Buck Topology
N787232
2 LED Strings up-to 60 V
FAWLYYWW
High Current Capability up to 1.6 A DC per Output
High Overall Efficiency
Minimum of External Components
N787230 = Specific Device Code
N787232 = Specific Device Code
Integrated High Accuracy Current Sensing
F = Fab Indicator
Integrated Switched Mode Buck Current Regulator
A = Assembly Location
Average Current Regulation through the LEDs WL = Wafer Lot
YY = Year
High Operating Frequencies to Reduce Inductor Sizes
WW = Work Week
Low EMC Emission for LED Switching and Dimming
= PbFree Package
SPI Interface for Dynamic Control of System Parameters
(Note: Microdot may be in either location)
Fail Safe Operating (FSO) Mode, Stand-Alone Mode
These Devices are PbFree, Halogen Free/BFR Free and are RoHS ORDERING INFORMATION
See detailed ordering and shipping information on page 31 of
Compliant
this data sheet.
Typical Applications
High Beam
Low Beam
DRL
Position or Park Light
Turn Indicator
Fog
Static Cornering
Semiconductor Components Industries, LLC, 2015
1 Publication Order Number:
January, 2020 Rev. 4 NCV78723/DNCV78723
TYPICAL APPLICATION SCHEMATIC
VBOOST
C_M3V
VBOOSTM3V VBOOST
LED-String 1
VINBCK1
C_BCK_1
LBCKSW1
L_BCK_1
LBCKSW1
D_1
R_LED_1
VLED1
External
ON Semiconductor
C_LED_1
VDD Supply
LED Driver
2-Channel Buck
LED-String 2
NCV78723
VDD
V of MCU
CC
VINBCK2
C_DD
C_BCK_2
LBCKSW2
R_SDO
L_BCK_2
LBCKSW2
D_2
R_LED_2
RSTB
VLED2
LEDCTRL1
C_LED_2
C
LEDCTRL2
SCLK
SDI
SDO
CSB
Figure 1. Typical Application Schematic
Table 1. EXTERNAL COMPONENTS
Component Function Typical Value Unit
L_BCK_x Buck Regulator Coil (see Buck Regulator Chapter for Details) 47 H
C_BCK_x Buck Regulator Output Capacitor (see Buck Regulator Chapter for Details) 220 nF
C_M3V Capacitor for M3V Regulator (see Table 6 VBOOSTM3V) nF
C_DD V Decoupling Capacitor 470 nF
DD
C_LED_x Optional VLEDx Pin Filter Capacitor (Note 2) 1 nF
R_LED_x VLEDx Pin Serial Resistor (Notes 2 and 3) Min. 1 k
R_SDO SPI Pull-Up Resistor 1 k
D_x Buck Regulator Free-Wheeling Diode e.g. MBRS2H100T3G
1. Pin TEST has to be connected to ground. TEST1 and TEST2 pins can be connected to ground or left floating.
2. C_LED_x is optional. If used, time constant of the C_LED_x and R_LED_x filter has to be lower than minimal LEDCTRLx ON time in PWM
dimming for proper VLED measurement.
3. R_LED_x is necessary to ensure Absolute Maximum Ratings of IVLEDx current (see Table 3).
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2
TEST
TEST1
TEST2
GND
EXPOSED
PAD