MAX17149ETE+T ,Low-Cost, 6-String WLED Drivers with Quick-PWM Step-Up ConvertersElectrical Characteristics(Circuit of Figure 1. V = 12V, R = 100kΩ, T = 0°C to +85°C, unless otherw ..
MAX1714A ,High-Speed Step-Down Controller for Notebook ComputersApplicationsV VCC DDNotebook ComputersSHDNV+CPU Core SupplyBSTILIMChipset/RAM Supply as Low as 1V O ..
MAX1714AEEP ,High-Speed Step-Down Controller for Notebook Computersapplications requiring VID compli-ance or DAC control of output voltage, refer to theMAX1710/MAX171 ..
MAX1714AEEP ,High-Speed Step-Down Controller for Notebook Computersapplications requiring VID compli-ance or DAC control of output voltage, refer to theMAX1710/MAX171 ..
MAX1714AEEP ,High-Speed Step-Down Controller for Notebook ComputersMAX171419-1536; Rev 1; 12/99High-Speed Step-Down Controllerfor Notebook Computers
MAX1714AEEP ,High-Speed Step-Down Controller for Notebook ComputersApplicationsV VCC DDNotebook ComputersSHDN V+CPU Core SupplyBSTILIMChipset/RAM Supply as Low as 1V ..
MAX4541EUA ,Low-Voltage, Single-Supply Dual SPST/SPDT Analog SwitchesMAX4541–MAX454419-1202; Rev 3; 8/02Low-Voltage, Single-Supply Dual SPST/SPDT Analog Switches
MAX4541EUA ,Low-Voltage, Single-Supply Dual SPST/SPDT Analog SwitchesFeaturesThe MAX4541–MAX4544 are precision, dual analog Low R : 60Ω max (33Ω typ)ONswitches design ..
MAX4541EUA+ ,Low-Voltage, Single-Supply Dual SPST/SPDT Analog SwitchesELECTRICAL CHARACTERISTICS—Single +5V Supply(V+ = +5V ±10%, GND = 0, V = 2.4V, V = 0.8V, T = T to T ..
MAX4542CSA ,Low-Voltage / Single-Supply Dual SPST/SPDT Analog SwitchesFeaturesThe MAX4541–MAX4544 are precision, dual analog Low R : 60Ω max (33Ω typ)ONswitches design ..
MAX4542CSA ,Low-Voltage / Single-Supply Dual SPST/SPDT Analog SwitchesGeneral Description ________
MAX4542CUA ,Low-Voltage / Single-Supply Dual SPST/SPDT Analog SwitchesELECTRICAL CHARACTERISTICS—Single +5V Supply(V+ = +5V ±10%, GND = 0, V = 2.4V, V = 0.8V, T = T to T ..
MAX17129ETE+-MAX17149ETE+T
Low-Cost, 6-String WLED Drivers with Quick-PWM Step-Up Converters
General DescriptionThe MAX17129/MAX17149 are high-efficiency drivers
for white LEDs. They are designed for small- to medium-
sized LCDs that employ an array of LEDs as the light
source. An internal switch step-up controller with Quick-
PWM™ drives the LED array, which can be configured for
up to 6 strings in parallel and either 11 LEDs (MAX17129)
or 6 LEDs in series (MAX17149) per string. Each string
is terminated with a ballast that achieves ±2% current-
regulation accuracy, ensuring even LED brightness and
provides an adjustable 10mA to 45mA full-scale LED
current. The devices have a wide input voltage range of
6V to 26V. The MAX17129 integrates an LDO to simplify
applications that have a single high-voltage supply. The
devices also feature a low-input-voltage mode for applica-
tions that have a 3V to 5.5V supply voltage.
The devices support both PWM and hybrid dimming
mode. In PWM dimming mode, the external PWM signal
directly controls the brightness of LEDs. The dimming fre-
quency ranges from 100Hz to 25kHz with 400ns minimum
on-time. In hybrid dimming mode, the LED current ampli-
tude can be adjusted to 25% of full-scale LED current to
improve system efficiency when brightness is low.
The devices have multiple features to protect the
controller from fault conditions. Separate voltage-
feedback loops limit the output voltage to safe operation.
The open- and short-LED detection shuts down the faulty
string while keeping other strings operating normally.
The devices feature cycle-by-cycle current limit on the
internal switch to provide consistent operation and soft-
start capability. If the devices are in current-limit condition,
the step-up converter is latched off after an internal timer
expires. A thermal-shutdown circuit provides another level
of protection and prevents ICs from damage.
The ICs’ step-up controller features an internal 0.25Ω
(typ), 48V (max) power MOSFET with lossless current
sense and accurate cycle-by-cycle current limit. The
Quick-PWM control architecture provides fast load-tran-
sient response without requiring an external loop com-
pensation component, simplifies the external circuitry, and
saves board area. The Quick-PWM control scheme has
constant off-time and adjustable pseudo-fixed frequency,
which enables a wide variety of applications that can trade
off component size for operating frequency. Low feedback
voltage at each LED string (275mV typ at 20mA LED
current) helps reduce power loss and improve efficiency.
The ICs are available in a 16-pin, thin QFN package with
0.5mm lead spacing. The package is 3mm x 3mm with a
maximum thickness of 0.8mm for ultra-thin LCD panel design.
Features●Independently Controlled Dual Paths●3V to 26V Input Supply Voltage●Up to Six Parallel Strings of Multiple Series-
Connected LEDs●Step-Up Regulator with Quick-PWM Control Scheme●Two-Level Selectable Switching Frequency●0.25Ω Internal HV Power MOSFET (48V max)●Low String Feedback Voltage: 275mV at 20mA LED
Current●Full-Scale LED Current Adjustable from 10mA to
45mA●±2% Current-Regulation Accuracy Between Strings●Support PWM and Hybrid Dimming Mode●100:1 Dimming Ratio●100Hz to 25kHz Dimming Frequency for PWM
Dimming Mode●Open- and Short-LED Protection●Output-Overvoltage Protection●Small 16-Pin, 3mm x 3mm Thin QFN Package
Applications●Notebook, Subnotebook, and Tablet Computer
Displays●Handy Terminals
Simplified Operating Circuit appears at end of data sheet.Quick-PWM is a trademark of Maxim Integrated Products, Inc.
+Denotes lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
PARTTEMP RANGEPIN-PACKAGE
MAX17129ETE +-40°C to +85°C16 Thin QFN-EP*
MAX17149ETE+-40°C to +85°C16 Thin QFN-EP*
MAX17129/MAX17149Low-Cost, 6-String WLED Drivers with
Quick-PWM Step-Up Converter
Ordering Information
EVALUATION KIT AVAILABLE
FSEL, IN, BRT, EN to GND ...................................-0.3V to +28V
FB_, LX, OVP to PGND..........................................-0.3V to +48V
PGND to GND.......................................................-0.3V to +0.3V
VCC to GND..............................................................-0.3V to +6V
ISET to GND................................................ -0.3V to VCC + 0.3V
LX Switch Continuous RMS Current......................................1.6A
Continuous Power Dissipation (TA = +70°C)
16-Pin Thin QFN (derate 14.7mW/°C above +70°C)..1176mW
Operating Temperature Range..............................-40°C to +85°C
Junction Temperature.......................................................+150°C
Storage Temperature Range...............................-60°C to +150°C
ESD
HBM..................................................................................±2kV
MM..................................................................................±200V
Lead Temperature (soldering, 10s)...................................+300°C
Soldering Temperature (reflow)........................................+260°C
(Circuit of Figure 1. VIN = 12V, RISET = 100kΩ, TA = 0°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETERCONDITIONSMINTYPMAXUNITSIN Input Voltage RangeIN not connected to VCC626VIN connected to VCC 3.05.5
IN Standby Current
VEN = 3V, VIN = 26V, no external loads3.24mA
VEN = 0V, VIN = 26V0.15µA
VCC Output VoltageVEN = 3V, 0 < IVCC < 10mA3.63.84.0V
VCC Current LimitVCC is forced to 3.5V; IN not connected to VCC153045mA
VCC UVLO ThresholdRising edge, typical hysteresis = 100mV2.752.82.85V
IN UVLO Threshold Rising edge, typical hysteresis = 100mV;
IN not connected to VCC5.55.755.9V
STEP-UP CONVERTERLX On-Resistance100mA from LX to PGND250500mΩ
LX Leakage CurrentVLX = 40V, TA = +25°C0.051µA
Off-TimeFSEL = GND, VIN = 12V, VOVP = 22V450500550ns
FSEL = VCC, VIN = 12V, VOVP = 22V90010001100
LX Peak Current LimitDuty cycle = 75% 2.533.5A
Minimum On-Time50ns
Minimum Output Regulation
Voltage
MAX17129 only1516.518V
MAX17149 only6.88.39.8V
Maximum Output Regulation
Voltage
MAX17129 only41.54344.5V
MAX17149 only23.925.426.9V
INPUT LEAKAGE/BIAS CURRENTSEN Bias Current0.3V < VEN < 3.5V, TA = +25°C6µA4.1V < VEN < 26V, TA = +25°C110
BRT Bias Current0.3V < VBRT < 3.5V, TA = +25°C15µA4.1V < VBRT < 26V, TA = +25°C 2000
EN Input Impedance7501500kΩ
OVP Input Current
MAX17129 only; VOVP = 40V, VFB = 0.75V1550µA
MAX17149 only; VOVP = 20V, VFB = 0.75V7.525µA
MAX17129/MAX17149Low-Cost, 6-String WLED Drivers with
Quick-PWM Step-Up Converter
Absolute Maximum RatingsStresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these
or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect
device reliability.
Electrical Characteristics
(Circuit of Figure 1. VIN = 12V, RISET = 100kΩ, TA = 0°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETERCONDITIONSMINTYPMAXUNITS
LED CURRENT SOURCEISET Resistance Range44250kΩ
Full-Scale FB_ Output Current
RISET = 44.44kΩ43.34547.7
RISET = 66.66kΩ29.13030.9
RISET = 100kΩ 19.42020.6
RISET = 133.33kΩ14.551515.45
RISET = 200kΩ 9.651010.35
RISET = 100kΩ, hybrid dimming mode4.455.6
RISET = 250kΩ, hybrid dimming mode1.422.6
ISET Output Voltage1.2251.2501.275V
Current Regulation Between
Strings
IFB_ = 30mA-1.5+1.5
IFB_ = 20mA-2.0+2.0
IFB_ = 15mA-2.0+2.0
IFB_ = 10mA-2.75+2.75
IFB_ = 5mA, hybid dimming ode-6.0+6.0
IFB_ = 2mA, hybrid dimming mode-15.0+15.0
Minimum FB_ Regulation Voltage
RISET = 66.66kΩ, 100% duty cycle375550RISET = 100kΩ, 100% duty cycle275365
RISET = 133.33kΩ, 100% duty cycle200275
RISET = 200kΩ, 100% duty cycle125200
FB_ On-Resistance VFB_ = 50mV20Ω
FB_ Leakage CurrentVFB_ = 28V, TA = +25°C, EN = 0V, VOVP = 28V 0.051µAVFB_ = 40V, TA = +25°C, EN = 0V, VOVP = 40V2.55
FB_ On-Time300ns
BRT Input High Level2.1V
BRT Input Low Level0.8V
BRT Dimming Frequency0.125kHz
EN Input High Level MAX17129/MAX17149 enabled, PWM dimming mode2.1VMAX17129/MAX17149 enabled, hybrid dimming mode1.41.8
EN Input Low Level0.8V
FAULT PROTECTIONOVP OvervoltageRising edge, hysteresis = 1.8V44.145.146.1V
FB_ Check LED Source Current0.600.6650.73mA
FB_ Check LED TimeSequence for 6 channels1ms
FB_ Open LED Threshold 500700mV
FB_ Overvoltage Threshold6.78.09.6V
Thermal-Shutdown Threshold(Note 2)+160°C
Thermal-Shutdown Hysteresis(Note 2)15°C
BOOST FREQUENCY SELECTION FSELMAX17129/MAX17149Low-Cost, 6-String WLED Drivers with
Quick-PWM Step-Up Converter
Electrical Characteristics (continued)
(Circuit of Figure 1. VIN = 12V, RISET = 100kΩ, TA = -40°C to +85°C, unless otherwise noted.) (Note 1)
PARAMETERCONDITIONSMINTYPMAXUNITSIN Input Voltage RangeIN not connected to VCC626V
IN = VCC 35.5
IN Quiescent CurrentVEN = 3V, VIN = 26V, no external loads4mA
VEN = 0V, VIN = 26V5µA
VCC Output VoltageVEN = 3V, 0 < IVCC < 10mA3.64.0V
VCC Current LimitVCC is forced to 3.5V; IN not connected to VCC1545mA
VCC UVLO ThresholdRising edge, typical hysteresis = 100mV2.752.85V
IN UVLO Threshold Rising edge, typical hysteresis = 100mV;
IN not connected to VCC5.55.9V
STEP-UP CONVERTERLX On-Resistance100mA from LX to PGND500mΩ
LX Leakage CurrentVLX = 40V, TA = +25°C1µA
Off-TimeFSEL = GND VIN = 12V, VOVP = 22V450550nsFSEL = VCC, VIN = 12V, VOVP = 22V9001100
LX Peak Current LimitDuty cycle = 75% 2.53.65A
Minimum Output Regulation
Voltage
MAX17129 only1518V
MAX17149 only6.89.8V
Maximum Output Regulation
Voltage
MAX17129 only41.544.5V
MAX17149 only23.926.9V
INPUT LEAKAGE/BIAS CURRENTSEN Bias Current 0.3V < VEN < 3.5V, TA = +25°C6µA
4.1V < VEN < 26V, TA = +25°C110
BRT Bias Current 0.3V < VBRT < 3.5V, TA = +25°C15µA4.1V < VBRT < 26V, TA = +25°C 2000
EN Input Impedance750kΩ
OVP Input CurrentMAX17129 only; VOVP = 40V, TA = +25°C, VFB = 0.75V50µA
MAX17149 only; VOVP = 20V, TA = +25°C, VFB = 0.75V25
FSEL Bias Current 0.3V < VFSEL < 3.5V6µA4.1V < VFSEL < 26V2000
LED CURRENT SOURCEISET Resistance Range44250kΩ
Full-Scale FB_ Output Current
RISET = 44.44kΩ43.347.7
RISET = 66.66kΩ29.130.9
RISET = 100kΩ19.420.6
RISET = 133.33kΩ14.5515.45
RISET = 200kΩ9.6510.35
RISET = 100kΩ, hybrid dimming mode4.45.6
MAX17129/MAX17149Low-Cost, 6-String WLED Drivers with
Quick-PWM Step-Up Converter
Electrical Characteristics
(Circuit of Figure 1. VIN = 12V, RISET = 100kΩ, TA = -40°C to +85°C, unless otherwise noted.) (Note 1)
Note 1: All devices are 100% production tested at TA = +25°C. Limits over temperature are guaranteed by design.
Note 2: Specifications are guaranteed by design, not production tested.
PARAMETERCONDITIONSMINTYPMAXUNITSCurrent Regulation Between
Strings
IFB_ = 30mA-1.5+1.5
IFB_ = 20mA-2.0+2.0
IFB_ = 15mA-2.0+2.0
IFB_ = 10mA-2.75+2.75
IFB_ = 5mA, hybrid dimming mode-6.0+6.0
IFB_ = 2mA, hybrid dimming mode-15.0+15.0
Minimum FB_ Regulation Voltage
RISET = 66.66kΩ, 100% duty cycle550RISET = 100kΩ, 100% duty cycle365
RISET = 133.33kΩ, 100% duty cycle275
RISET = 200kΩ, 100% duty cycle200
FB_ On-Resistance VFB_ = 50mV 20Ω
FB_ Leakage CurrentVFB_ = 28V, TA = +25°C, EN = GND, VOVP = 28V1µAVFB_ = 40V, TA = +25°C, EN = GND, VOVP = 40V5
FB_ On-Time300ns
BRT Input High Level2.1V
BRT Input Low Level0.8V
BRT Dimming Frequency0.125kHz
EN Input High Level MAX17129/MAX17149 enabled, PWM dimming mode2.1VMAX17129/MAX17149 enabled, hybrid dimming mode1.41.8
EN Input Low Level0.8V
FAULT PROTECTIONOVP OvervoltageRising edge, hysteresis = 1.8V 44.146.1V
FB_ Check LED Source Current0.600.73mA
FB_ Open LED Threshold700 mV
FB_ Overvoltage Threshold6.79.7V
BOOST FREQUENCY SELECTION FSELFSEL Input High Level Select fSW = 500kHz2.1V
FSEL Input Low LevelSelect fSW = 1000kHz0.8V
MAX17129/MAX17149Low-Cost, 6-String WLED Drivers with
Quick-PWM Step-Up Converter
Electrical Characteristics (continued)
(Circuit of Figure 1. VIN = 12V, TA = +25°C, unless otherwise noted.)
BOOST CONVERTER EFFICIENCY
vs. BRIGHTNESS
(VIN = 12V, VOUT = 31.8V/IOUT = 120mA
AT 100%)MAX17129 toc02
BRIGHTNESS (%)
EFFICIENCY (%)604020100
LED CURRENT vs. BRIGHTNESS SETTINGMAX17129 toc03
PWM DUTY CYCLE (%)
LED CURRENT (mA)604020
fBRT = 200Hz
LED CURRENT (ILED = 20mA AT
100% BRIGHTNESS) vs. INPUT VOLTAGEMAX17129 toc04
INPUT VOLTAGE (V)
LED CURRENT (mA)201714118
LED CURRENT (ILED = 20mA AT
10% BRIGHTNESS) vs. INPUT VOLTAGE
MAX17129 toc05
INPUT VOLTAGE (V)
LED CURRENT (mA)201714118
IN QUIESCENT CURRENT
vs. IN VOLTAGE
MAX17129 toc06
IN QUIESC
ENT CURRENT (mA)20171411826
100% BRIGHTNESS
200Hz/1% BRIGHTNESS
BOOST CONVERTER EFFICIENCY
vs. INPUT VOLTAGE
(VOUT = 31.8V/IOUT = 120mA,
BRIGHTNESS = 100%)MAX17129 toc01
INPUT VOLTAGE (V)
EFFICIENCY (%)20811141726
STARTUP WAVEFORMS
(BRIGHTNESS = 100%)MAX17129 toc07
VEN
5V/div
VLX
50V/div
VOUT
20V/div
INDUCTOR
CURRENT
500mA/div
4ms/div
12V
MAX17129/MAX17149Low-Cost, 6-String WLED Drivers with
Quick-PWM Step-Up Converter
Typical Operating Characteristics
(Circuit of Figure 1. VIN = 12V, TA = +25°C, unless otherwise noted.)
STARTUP WAVEFORMS
(BRIGHTNESS = 20%)MAX17129 toc08
VEN
5V/div
VLX
50V/div
VOUT
20V/div
INDUCTOR
CURRENT
500mA/div
4ms/div
12V
SWITCHING WAVEFORMS
(VIN = 12V, BRIGHTNESS = 100%)MAX17129 toc09
VLX
20V/div
INDUCTOR
CURRENT
500mA/div
0mA
1µs/div
LED OPEN FAULT PROTECTION
(BRIGHTNESS = 100%, LED OPEN ON FB1)MAX17129 toc10
VFB1
1V/div
VFB2
10V/div
VOUT
10V/div
IFB2
10mA/div
0mA
2ms/div
31.8V
20mA
LED SHORT FAULT PROTECTION
(BRIGHTNESS = 100%,
3 LEDS SHORT ON FB1)MAX17129 toc11
VFB1
10V/div
IFB1
20V/div
IFB2
20mA/div
0mA
0mA
2ms/div
20mA
20mA
MAX17129/MAX17149Low-Cost, 6-String WLED Drivers with
Quick-PWM Step-Up Converter
Typical Operating Characteristics (continued)
(Circuit of Figure 1. VIN = 12V, TA = +25°C, unless otherwise noted.)
LINE TRANSIENT RESPONSE
(VIN = 21V↔9V, BRIGHTNESS = 100%)MAX17129 toc13
VIN
10V/div
INDUCTOR
CURRENT
500mA/div
IFB1
20mA/div
VOUT
(AC-COUPLED)
200mV/div
0mA
200µs/div
20mA
21V
MAXIMUM UNBALANCE RATE
BETWEEN STRINGS vs. BRIGHTNESS
(VIN = 12V, fBRT = 200Hz, ILED = 20mA)MAX17129 toc14
BRIGHTNESS (%)
MAXIMUM UNBALANCE RATE (%)80706050403020
MAX. UNBALANCE
RATE (%) =IFB_-IFB(AVG) MAX
IFB(AVG)
MAXIMUM UNBALANCE RATE
BETWEEN STRINGS
(ILED = 20mA AT 100% BRIGHTNESS)
vs. INPUT VOLTAGEMAX17129 toc15
INPUT VOLTAGE (V)
MAXIMUM UNBALANCE RATE (%)211815129
MAX. UNBALANCE
RATE (%) =
IFB_-IFB(AVG) MAX
IFB(AVG)
LINE TRANSIENT RESPONSE
(VIN = 9V↔21V, BRIGHTNESS = 100%)MAX17129 toc12
VIN
10V/div
INDUCTOR
CURRENT
500mA/div
IFB1
20mA/div
VOUT
(AC-COUPLED)
500mV/div
0mA
100µs/div
20mA
21V
MAX17129/MAX17149Low-Cost, 6-String WLED Drivers with
Quick-PWM Step-Up Converter
Typical Operating Characteristics (continued)
PINNAMEFUNCTIONBRTPWM Signal Input. This PWM signal controls the LED brightness by turning the LED current sources on
or off.VCC
Internal LDO Output. VCC provides bias supply to the devices. VCC is generated by internal LDO.
Connect a minimum 1µF capacitor from VCC to GND. All power outputs are disabled until VCC
exceeds its UVLO threshold. See the Input Supply Voltage Coniguration and UVLO section for supply conigurations for the ICs.IN
Supply Input. Connect IN to the system input supply voltage and bypass IN to GND with a minimum
0.1µF ceramic capacitor. The ICs are disabled if VIN falls below its UVLO threshold. The devices can
extend the operating range down to 3.0V if IN and VCC are tied together. See the Input Supply Voltage Coniguration and UVLO section.FSELStep-Up Converter Switching Frequency Selection Input. Connect to VCC with a 10kΩ resistor to set
500kHz, or connect to GND to set 1MHz.LXStep-Up Regulator Switching Node. Connect inductor and output diode here and minimize trace area for
lowest EMI.PGNDPower GroundOVPBoost Output Voltage-Sensing Input. This voltage is used for overvoltage protection. FB1
Current-Balancer Output. LED string cathode connection. FB1 is the open-drain output of an internal
regulator, which controls current through FB1. FB1 can sink up to 45mA. If unused, connect FB1 to GND
or leave high impedance.FB2
Current-Balancer Output. LED string cathode connection. FB2 is the open-drain output of an internal
regulator, which controls current through FB2. FB2 can sink up to 45mA. If unused, connect FB2 to GND
or leave high impedance.
FSEL
BRT
FB3FB2FB53
GND109
ISETEP
FB1
OVP
PGND
MAX17129
MAX17149FB4
FB6
THIN QFN
3mm × 3mmTOP VIEW
MAX17129/MAX17149Low-Cost, 6-String WLED Drivers with
Quick-PWM Step-Up Converter
Pin Description
Pin Coniguration
PINNAMEFUNCTIONFB3
Current-Balancer Output. LED string cathode connection. FB3 is the open-drain output of an internal
regulator, which controls current through FB3. FB3 can sink up to 45mA. If unused, connect FB3 to GND
or leave high impedance.FB4
Current-Balancer Output. LED string cathode connection. FB4 is the open-drain output of an internal
regulator, which controls current through FB4. FB4 can sink up to 45mA. If unused, connect FB4 to GND
or leave high impedance.FB5
Current-Balancer Output. LED string cathode connection. FB5 is the open-drain output of an internal
regulator, which controls current through FB5. FB5 can sink up to 45mA. If unused, connect FB5 to GND
or leave high impedance.FB6
Current-Balancer Output. LED string cathode connection. FB6 is the open-drain output of an internal
regulator, which controls current through FB6. FB6 can sink up to 45mA. If unused, connect FB6 to GND
or leave high impedance.GNDAnalog Ground. Connect to ISET resistor ground as close as possible.ISET
Full-Scale LED Current-Adjustment Pin. The resistance from ISET to GND controls the full-scale current
in each LED string:
ILED_FS = 20mA x 100kΩ/RISETThe acceptable resistance range is 44.44kΩ < RISET < 200kΩ, which corresponds to full-scale LED
current of 45mA > ILED_FS > 10mA.EN
Enable and Dimming Mode Selection Input. Pull EN higher than 2.1V to enable the device, and lower than 0.8V
to disable the device. When VEN is higher than 2.1V, direct PWM mode is selected; when VEN is between 1.4V and 1.8V, hybrid dimming mode is selected. While selecting hybrid dimming mode, the device irst needs
to be enabled.EPExposed Backside Pad. Solder to the circuit board ground plane with suficient copper connection to
ensure low thermal resistance. See the PCB Layout Guidelines section.
MAX17129/MAX17149Low-Cost, 6-String WLED Drivers with
Quick-PWM Step-Up Converter
Pin Description (continued)
The MAX17129 typical operating circuit is shown in
Figure 1. Table 1 lists some recommended components,
and Table 2 lists the contact information for component
suppliers.
Figure 1. MAX17129 Typical Operating Circuit
Table 1. Component List
Table 2. Component Suppliers
DESIGNATIONDESCRIPTIONCIN
4.7µF ±10%, 25V X5R ceramic capacitor
(1206)
Murata GRM319R61E475KA12D
C1, C2
2.2µF ±20%,50V X7R ceramic capacitors
(1206)
Murata GRM31CR71H225K2A, 40V Schottky diode (M-lat)
Toshiba CMS1110µH, 1.5A, H = 1.2mm
VLP6812T-100M1R5
White LED3.2V (typ), 3.5V (max) at 20mA
Nichia NSSW008C
SUPPLIERPHONEWEBSITEMurata Electronics
North America, Inc. 770-436-1300www.murata.com
Nichia Corp.248-352-6575www.nichia.com
Sumida Corp. 847-545-6700www.sumida.com
Toshiba America
Electronic
Components, Inc.
949-623-2900www.toshiba.com/taec
Vishay402-563-6866www.vishay.com
2.2µF
1µF
RISET
100kΩ
CIN
4.7µF
VIN
6V TO 26V
10µH
2.2µF
PGND
OVP
FB1
FB2
FB3
FB4
FB5
FB6
VCC
ISET
BRT
GND
100Hz TO 25kHz
FSEL
0.1µF
MAX17129MAX17129/MAX17149Low-Cost, 6-String WLED Drivers with
Quick-PWM Step-Up Converter
Typical Operating Circuit
