|
|
PDF LD7551C Data sheet ( Hoja de datos )
| Número de pieza | LD7551C | |
| Descripción | Green-Mode PWM Controller | |
| Fabricantes | Leadtrend Technology | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de LD7551C (archivo pdf) en la parte inferior de esta página. Total 17 Páginas | ||
|
No Preview Available !
LD7551C
4/17/2009
Green-Mode PWM Controller with Frequency Trembling
and Integrated Protections
REV: 00
General Description
The LD7551C is built-in with several functions, protections
and an EMI-improved solution in a SOT-26 package. It
takes less components counts or circuit space, especially
ideal for those cost sensitive applications.
The LD7551C integrates low startup current, green-mode
power-saving operation, leading-edge blanking of the
current sensing and internal slope compensation. It also
features protections like OLP (Over Load Protection) and
OVP (Over Voltage Protection) to prevent the circuit
damage under the abnormal conditions.
Furthermore, the frequency trembling function is to reduce
the noise level and help the power circuit designers for the
EMI filter design with minimum component cost and
developing time.
Features
z High-Voltage CMOS Process with Excellent ESD
protection
z Very Low Startup Current (<20μA)
z Current Mode Control
z Non-audible-noise Green Mode Control
z UVLO (Under Voltage Lockout)
z LEB (Leading-Edge Blanking) on CS Pin
z Programmable Switching Frequency
z Internal Trembling (±4KHz)
z Internal Slope Compensation
z OVP (Over Voltage Protection) on Vcc Pin
z OLP (Over Load Protection)
z 500mA Driving Capability
Applications
z Switching AC/DC Adaptor and Battery Charger
z Open Frame Switching Power Supply
Typical Application
AC EMI
input Filter
VCC
RT
100K Ohm
COMP
32V
16.0V
/10.0V
UVLO
LD7551C
FM OSC
Divider
Control
Logic
GND
OUT
CS
Leadtrend Technology Corporation
LD7551C-DS-00 April 2009
1
www.leadtrend.com.tw
photocoupler
TL431
1 page  
Electrical Characteristics
(TA = +25oC unless otherwise stated, VCC=15.0V)
PARAMETER
CONDITIONS
Supply Voltage (Vcc Pin)
Startup Current
Operating Current
(with 1nF load on OUT pin)
VCOMP=0V
VCOMP=3V
Protection tripped (OLP)
Protection tripped (OVP)
UVLO (off)
UVLO (on)
OVP Level
Voltage Feedback (Comp Pin)
Short Circuit Current
Open Loop Voltage
Green Mode Threshold VCOMP
VCOMP=0V
COMP pin open
Current Sensing (CS Pin)
Maximum Input Voltage, Vcs(off)
Leading Edge Blanking Time
Input impedance
Delay to Output
Oscillator for Switching Frequency
Frequency
Green Mode Frequency
Trembling Frequency
Temp. Stability
Voltage Stability
RT=100KΩ
Fs=65kHz
(-40°C ~105°C)
(VCC=11V-25V)
Gate Drive Output (OUT Pin)
Output Low Level
Output High Level
Rising Time
Falling Time
VCC=15V, Io=20mA
VCC=15V, Io=20mA
Load Capacitance=1000pF
Load Capacitance=1000pF
OLP (Over Load Protection)
OLP Trip Level
OLP Delay Time
Vcomp (OLP)
Fs=65kHz
* RT value is in proportion to OLP delay time.
LD7551C
MIN TYP MAX UNITS
9.0
15.0
26.8
12
2.8
3.0
0.6
0.7
10.0
16.0
28.0
20
3.5
11.0
17.0
29.2
μA
mA
mA
mA
mA
V
V
V
1.37
5.9
2.35
2.2
mA
V
V
0.80
1
0.85
240
100
0.90
V
nS
MΩ
nS
60 65 70 KHz
21 KHz
± 4.0
KHz
5%
1%
1V
8V
90 180 nS
30 60 nS
5.0 V
50 mS
Leadtrend Technology Corporation
LD7551C-DS-00 April 2009
5
www.leadtrend.com.tw
5 Page 
Fig. 19
LD7551C
Fault Protection
There are several critical protections integrated in the
LD7551C to prevent the power supply or adapter from being
damaged. Those damages usually come from open or short
condition on the pins of LD7551C.
Under the conditions listed below, the gate output will turn
off immediately to protect the power circuit ---
1. RT pin short to ground
2. RT pin floating
3. CS pin floating
Leadtrend Technology Corporation
LD7551C-DS-00 April 2009
11
www.leadtrend.com.tw
11 Page | ||
| Páginas | Total 17 Páginas | |
| PDF Descargar | [ Datasheet LD7551C.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| LD7551C | Green-Mode PWM Controller | Leadtrend Technology |
| 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 |