|
|
PDF MAX17149 Data sheet ( Hoja de datos )
| Número de pieza | MAX17149 | |
| Descripción | (MAX17129 / MAX17149) 6-String WLED Drivers | |
| Fabricantes | Maxim Integrated Products | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de MAX17149 (archivo pdf) en la parte inferior de esta página. Total 21 Páginas | ||
|
No Preview Available !
EVALUATION KIT AVAILABLE
MAX17129/MAX17149
Low-Cost, 6-String WLED Drivers with
Quick-PWM Step-Up Converter
General Description
The 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
Ordering Information
PART
TEMP RANGE PIN-PACKAGE
MAX17129ETE + -40°C to +85°C 16 Thin QFN-EP*
MAX17149ETE+ -40°C to +85°C 16 Thin QFN-EP*
+Denotes lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
Simplified Operating Circuit appears at end of data sheet.
Quick-PWM is a trademark of Maxim Integrated Products, Inc.
19-5676; Rev 2; 11/14
1 page  
MAX17129/MAX17149
Low-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)
PARAMETER
CONDITIONS
MIN TYP MAX
Current Regulation Between
Strings
Minimum FB_ Regulation Voltage
FB_ On-Resistance
FB_ Leakage Current
FB_ On-Time
IFB_ = 30mA
IFB_ = 20mA
IFB_ = 15mA
IFB_ = 10mA
IFB_ = 5mA, hybrid dimming mode
IFB_ = 2mA, hybrid dimming mode
RISET = 66.66kΩ, 100% duty cycle
RISET = 100kΩ, 100% duty cycle
RISET = 133.33kΩ, 100% duty cycle
RISET = 200kΩ, 100% duty cycle
VFB_ = 50mV
VFB_ = 28V, TA = +25°C, EN = GND, VOVP = 28V
VFB_ = 40V, TA = +25°C, EN = GND, VOVP = 40V
-1.5
-2.0
-2.0
-2.75
-6.0
-15.0
300
+1.5
+2.0
+2.0
+2.75
+6.0
+15.0
550
365
275
200
20
1
5
BRT Input High Level
2.1
BRT Input Low Level
0.8
BRT Dimming Frequency
0.1 25
EN Input High Level
MAX17129/MAX17149 enabled, PWM dimming mode
MAX17129/MAX17149 enabled, hybrid dimming mode
2.1
1.4
1.8
EN Input Low Level
0.8
FAULT PROTECTION
OVP Overvoltage
Rising edge, hysteresis = 1.8V
44.1
46.1
FB_ Check LED Source Current
0.60
0.73
FB_ Open LED Threshold
700
FB_ Overvoltage Threshold
6.7 9.7
BOOST FREQUENCY SELECTION FSEL
FSEL Input High Level
Select fSW = 500kHz
2.1
FSEL Input Low Level
Select fSW = 1000kHz
0.8
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.
UNITS
%
mV
Ω
µA
ns
V
V
kHz
V
V
V
mA
mV
V
V
V
www.maximintegrated.com
Maxim Integrated │ 5
5 Page 
MAX17129/MAX17149
Low-Cost, 6-String WLED Drivers with
Quick-PWM Step-Up Converter
VIN
6V TO 26V
CIN
4.7µF
L1
10µH
0.1µF
IN
FSEL
LX
1µF
RISET
100kΩ
VCC
ISET
EN
100Hz TO 25kHz
BRT
GND
MAX17129
EP
PGND
OVP
FB1
FB2
FB3
FB4
FB5
FB6
D1
C1
2.2µF
C2
2.2µF
Figure 1. MAX17129 Typical Operating Circuit
Table 1. Component List
DESIGNATION
CIN
DESCRIPTION
4.7µF ±10%, 25V X5R ceramic capacitor
(1206)
Murata GRM319R61E475KA12D
C1, C2
2.2µF ±20%,50V X7R ceramic capacitors
(1206)
Murata GRM31CR71H225K
D1
L1
White LED
2A, 40V Schottky diode (M-flat)
Toshiba CMS11
10µH, 1.5A, H = 1.2mm
VLP6812T-100M1R5
3.2V (typ), 3.5V (max) at 20mA
Nichia NSSW008C
Typical Operating Circuit
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.
Table 2. Component Suppliers
SUPPLIER
Murata Electronics
North America, Inc.
Nichia Corp.
Sumida Corp.
Toshiba America
Electronic
Components, Inc.
Vishay
PHONE
WEBSITE
770-436-1300 www.murata.com
248-352-6575 www.nichia.com
847-545-6700 www.sumida.com
949-623-2900 www.toshiba.com/taec
402-563-6866 www.vishay.com
www.maximintegrated.com
Maxim Integrated │ 11
11 Page | ||
| Páginas | Total 21 Páginas | |
| PDF Descargar | [ Datasheet MAX17149.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| MAX1714 | High-Speed Step-Down Controller for Notebook Computers |  Maxim Integrated |
| MAX17149 | (MAX17129 / MAX17149) 6-String WLED Drivers | Maxim Integrated Products |
| Número de pieza | Descripción | Fabricantes |
| SLA6805M | High Voltage 3 phase Motor Driver IC. |
 Sanken |
| SDC1742 | 12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters. |
 Analog Devices |
|
DataSheet.es es una pagina web que funciona como un repositorio de manuales o hoja de datos de muchos de los productos más populares, |
| DataSheet.es | 2020 | Privacy Policy | Contacto | Buscar |