Part Number: LD7576A
Function: Green-Mode PWM Controller
Package: DIP 8 Pin, SOP 7, SOP 8 Pin type
Manufacturer: Leadtrend
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Description
The LD7576A brings hi gh performance, and com bines highly inte grated functions, protections an d EMI-improve solution. It’s cost. The LD7576A features near-lossless high v oltage startup circuit, green-mode power-saving operation, leading-edge blanking of the curre compensation. nt sensi ng an d i nternal slop e They are also equipped with protections, an id eal so lution for those cost-sensitive systems, redu cing comp onent count and overa ll s ystem.
Features
1. High-Voltage (500V) Startup Circuit
2. Current Mode Control
3. Non-Audible-Noise Green Mode Control
4. UVLO (Under Voltage Lockout)
5. LEB (Leading-Edge Blanking) on CS Pin
6. Internal Slope Compensation
7. OVP (Over Voltage Protection) on Vcc
8. On-Chip OTP (Over Temperature Protection)
9. OLP (Over Load Protection)
10. 500mA Driving Capability
11. Adjustable OLP delay time
Applications:
1. Switching AC/DC Adaptor and Battery Charger
2. Open Frame Switching Power Supply
3. LCD Monitor/TV Power
Pin Descriptions :
PIN 1 CT NAME FUNCTION This pin is to program the frequ ency of a lo wer freq uency timer. Connecting a capacitor to ground sets the OLP delay time. Voltage fee dback pi n (sam e as th e CO MP pin in UC384X). Co nnecting a 2 COMP photo-coupler closes the co ntrol loo p to achieve the regu lation. A high qu ality ceramic capacitor (X7R), with capacitance of 102pF at least, is required for gen eral applications. 3 4 GND 5 6 7 NC CS Current sense pin, for sensing the MOSFET current. Ground. OUT VCC Gate drive output to drive an external MOSFET. Supply voltage pin. Unconnected Pin. Connect this p in to a p ositive termina l of a bulk c apacitor to provi de t he startup 8 HV current for the control ler. When Vcc voltage trips up to the UVLO(on), this HV loop will be off to save the power loss on the startup circuit. 2 Leadtrend Technology Corporation LD7576A-DS-00b November , 2009 www.leadtrend.com.tw GND GND CT LD7576A Block Diagram ∑ 3 Leadtrend Technology Corporation LD7576A-DS-00b November , 2009 www.leadtrend.com.tw LD7576A Absolute Maximum Ratings […]
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