|
|
PDF WS3412 Data sheet ( Hoja de datos )
| Número de pieza | WS3412 | |
| Descripción | Active PFC Non-isolated Buck LED Driver | |
| Fabricantes | WINSEMI | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de WS3412 (archivo pdf) en la parte inferior de esta página. Total 8 Páginas | ||
|
No Preview Available !
WS3412 Product Description
WS3412 Active PFC Non-isolated Buck LED Driver
Features
� High Power Factor Correction, Low Total Harmonic
Distortion
� Dynamic Temperature Compensation
� 550V Power MOSFET Integrated
� No Auxiliary Winding For Supplying
� SOP8 Package, Up To 260mA Output Current
� Valley Switching, High efficiency, Low EMI
� Automatic Compensate the Inductance Variation
� Automatic Adapt to the Change of Output Voltage
� LED Short Circuit Protection
� Over Voltage Protection
� Over Temperature Protection
� Open Circuit Protection
� Few External Components
Applications
� LED Driver Supply
Typical Application Circuit
General Description
The WS3412 is designed for active PFC non-isolated buck
LED driver. It operates at valley switching mode with high
efficiency, low EMI and High PF. The output current
automatically adapt to the variation of the inductance and the
output voltage. The truly constant current LED is realized.
The WS3412 integrates 550V power MOSFET, using SOP 8
package, producing up to 260mA output current.
It can achieve excellent constant current performance with
very few external components.
The WS3412 offers rich protection functions, including over
voltage protection, LED short circuit protection, cycle by cycle
current limiting, dynamic temperature compensation, over
temperature protection and soft start.
WS3412 consumes very low start current and operation
current, driving LED efficiently under universal AC
input(85VAC~265VAC).
WS3412 is available in SOP8 package.
5D
CS 8
6D
CS 7
3 VCC
FB 4
AC
2 GND
COMP 1
LED+
LE D-
WIN SEM I M ICROELECTRON ICS
WIN SEM I M ICROELECTRON ICS
WIN SEM I M ICROELECTRON ICS
Copyr ight@Winsemi Microelectronics Co., Ltd., All right reserved.
WIN SEM I M ICROELECTRON ICS
W/T-S031-Rev.A/ 0 Nov.2013
WIN SEM I M ICROELECTRON ICS
0214
1 page  
WS3412 Product Description
Function Description
The WS3412 is designed for active PFC non-isolated buck
LED driver, which integrates 550V power MOSFET and
using SOP 8 package, producing up to 260mA output
current. It operates under valley switching mode,
automatically adapting to the variation of the inductance and
the output voltage.
It can achieve excellent constant current performance with
very few external components.
Start up
The start current is very low, Typ. 70uA(Max. 100uA). Under
the design system of 85VAC, the startup resistor is:
R = 85 * 2 = 1.2M
100
Chip Supply
strongest power supply):
D=80/260/1.414=0.218
The power consumption of R4:
P=(80-9)*(80-9)/58*(1-0.218)=68mW
Sence Resistor
The WS3412 is designed for active PFC non-isolated buck
LED driver. It operates under valley switching mode and
can achieve high accuracy constant current performance
with very few external components. The peak current of
inductor is continuous detected. CS terminal is connected
internal of the chip, and compared with the internal 200mV.
Internal Amplifier’s output COMP adjust the on-time, making
the average value os CS equal to 200mV after the system is
stable. In addition, a 1V cycle-by-cycle over current
protection is set up inside CS pin.
LED output current:
I LED
=
0.2V
R CS
After startup, the output voltage should supply the chip,
rectifier diodes D6 need to use fast recovery diodes.Current
FB Voltage Detection
limiting resistor R4 is calculated as:
R4
=
(1 − )D * VLED − 9
400uA
FB voltage determines the working status of the system,
when FB is greater then 1.6V(typ.), WS3412 will
automatically considered as output over voltage protection.
Where, D is duty cycle, 400uA is the normal operation
The system will enter extremely energy efficient hiccup
current of the chip, Vled is output load voltage. The
mode. Output over voltage protection voltage as follows:
consumption of R4 is:
PR 4
=
(VLED − 9)2
R4
* (1 −
D)
VOVP
= 1.6 *
R2 + R3
R3
R2,R3,please refer to the typical application diagram, in
For example:
which R3=1k(no more than 2k). use 1.3 instead of constant
Requirements:180~260V input voltage, 36~80V output,
1.6 in the above formula in the design of system. Assuming
240mA output current.
Vovp=90V, we got R2=56k from the above formula,
The R4 design of above program should be met:
choosing 60k for R2 (larger as far as possible).
1. Supply Problem when Min. input AC voltage 180V and
Because VFB2 is between 1.3 and 1.9, choose 1.9 to
Min. output voltage 36V(which is the weakest power supply):
calculate the withstand voltage of C4,
D=36/180/1.414=0.141,R4=(1-0.141)*(36-9)/400uA=58k
Vovp=1.9*(1+60)/1=116V
2.Power consumption problem of R4 when Max. input AC
The withstand voltage of C4 shoule larger than the above
voltage 260V and Max. output voltage 80V(which is the
value, 200V capacitor could be used.
WIN SEM I M ICROELECTRON ICS
WIN SEM I M ICROELECTRON ICS
WIN SEM I M ICROELECTRON ICS
www.winsemi.com Tel : 0755-82506288 Fax : 0755-82506299
WIN SEM I M ICROELECTRON ICS
WIN SEM I M ICROELECTRON ICS
5/8
5 Page | ||
| Páginas | Total 8 Páginas | |
| PDF Descargar | [ Datasheet WS3412.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| WS3410 | Active PFC Non-isolated Buck LED Driver | WINSEMI |
| WS3411 | Active PFC Non-isolated Buck LED Driver | WINSEMI |
| WS3411H | Non-isolated Buck APFC Offline LED Driver | WINSEMI |
| WS3412 | Active PFC Non-isolated Buck LED Driver | WINSEMI |
| 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 |