|
|
Número de pieza | YB1518 | |
Descripción | Step-up DC-DC Converter White LED Driver | |
Fabricantes | YOBON TECHNOLOGIES | |
Logotipo | ||
Hay una vista previa y un enlace de descarga de YB1518 (archivo pdf) en la parte inferior de esta página. Total 12 Páginas | ||
No Preview Available ! www.DataSheet4U.com
YB1518
Step-up DC-DC Converter White LED Driver
Description
Features
The YB1518 is a step-up DC-DC converter;
operates as current source to drive up to 6
white LEDs(VIN at 3.0V) or 8 LEDs(VIN at
3.4V) or 9 LEDs(VIN at 3.4V) in series.
Series connecting of the LEDs provides
identical LED currents resulting in uniform
brightness and eliminating the need for
ballast resistors. The light intensity of these
LEDs is proportional to the current passing
through them. The YB1518 switches at a
fixed frequency of ~1MHz, allowing the use
of tiny, low profile inductors and capacitors
to minimize footprint and cost in space
consideration applications for cellular
phone backlighting or other hand held
equipment.
The YB1518 can drive up to 9 white LEDs
from a single Li-Ion battery. The wide input
voltage range from 2.7V to 16V is ideal for
portable and automotive (5V/12V)
applications with higher conversion
efficiency. To control LED brightness, the
LED current can be pulsed by applying a
PWM (pulse width modulated) signal with a
frequency range of 100Hz to 1KHz to the
CTRL pin.
YB1518 has integrated Latched Over
Voltage Protection that prevents damage to
the device in case of a high impedance
output due to faulty LED or open circuit
caused by abnormal conditions.
Built-in internal switch
2.7V to 16V input range
<1uA shutdown current
High efficiency
Internal Soft Start
Drives up to 9 white LEDs(VIN at 3.4V)
Over voltage protection 36V
Small 5-Lead SOT-23 package
100mV Low Reference Voltage
Applications
LCD Display Module
White LED Backlighting
PDAs, GPS terminals
Digital Cameras
Cellular Phone
Electronic Books
Portable Applications
Typical Application Circuit
YB1518 MRev.1.2
Figure 1: Typical Application Circuit
www.yobon.com.tw
1
1 page www.DataSheet4U.com
YB1518
Step-up DC-DC Converter White LED Driver
Condition : Vin 2.8V ; 4.4V / Vctrl : 3V
VOUT ; 4pcs white LEDs
Condition : Vin 2.8V ; 4.4V / Vctrl : 3V
VOUT ; 5pcs white LEDs
Efficiency vs Vin (4WLEDs)
83
82
81
80
79
2.7 3.0 3.3 3.6 3.9 4.2 4.5
Vin(V)
Efficiency vs Vin (5WLEDs)
83
81
79
77
75
2.7 3.0 3.3 3.6 3.9 4.2 4.5
Vin(V)
YB1518 MRev.1.2
www.yobon.com.tw
5
5 Page www.DataSheet4U.com
YB1518
Step-up DC-DC Converter White LED Driver
Although small size and high efficiency are
major concerns, the inductor should have
low core losses at 1MHz and low DCR
(copper wire resistance).
Diode Selection
To maintain high efficiency, the average
current rating of the Schottky diode should
be large than the peak inductor current, IPK.
Schottky diode with a low forward drop and
fast switching speeds are ideal for increase
efficiency in portable application. Choose a
reverse breakdown of the Schottky diode
large than the output voltage.
Capacitor Selection
Choose low ESR capacitors for the output
to minimize output voltage ripple. Multilayer
capacitors are a good choice for this as well.
A 1uF capacitor is sufficient for 2~6 LEDs,
2.2uF is for 7~8 LEDs and 4.7uF is for 9
LEDs applications. For additional
bypassing, a 100nF ceramic capacitor can
be used to shunt high frequency ripple on
the input.
The input bypass capacitor Cin, as shown
in Figure 1, must be placed close to the IC.
This will reduce copper trace resistance
which affects input voltage ripple of the IC.
For additional input voltage filtering, a
100nF bypass capacitor can be placed in
parallel with Cin to shunt any high
frequency noise to ground. The output
capacitor, Cout, should also be placed
close to the IC. Any copper trace
connections for the Cout capacitor can
increase the series resistance, which
directly effect output voltage ripple.
The feedback network, resister R2 should
be kept close to the FB pin to minimize
copper trace connections that can inject
noise into the system. The ground
connection for the feedback resistor
network should connect directly to an
analog ground plane. The analog ground
plane should tie directly to the GND pin. If
no analog ground plane is available, the
ground connection for the feedback
network should tie directly to the GND pin.
Trace connections made to the inductor
and Schottky diode should be minimized to
reduce power dissipation and increase
overall efficiency.
YB1518 MRev.1.2
www.yobon.com.tw
11
11 Page |
Páginas | Total 12 Páginas | |
PDF Descargar | [ Datasheet YB1518.PDF ] |
Número de pieza | Descripción | Fabricantes |
YB1510 | Step-up DC-DC Converter | YOBON TECHNOLOGIES |
YB1517 | Step-up DC-DC Converter & White LED Driver | YOBON TECHNOLOGIES |
YB1518 | Step-up DC-DC Converter White LED Driver | YOBON TECHNOLOGIES |
YB1519 | High-Power White LED Driver | YOBON TECHNOLOGIES |
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 |