ZA8726H & ZA8756H Description(High Efficiency LED Buck Controller)
The ZA8726H/ZA8756H integrates a non-isolation LED buck controller and 600V of high voltage MOSFET into SOP8 package. It provides a simple circuit to get higher power factor, higher efficiency and accuracy constant current; hence ZA8726H/ZA8756H can meet LED lighting requirements and reduce the cost of LED power supply. The ZA8726H/ZA8756H has a 45kHz fixed frequency oscillator, an internal 200mV precision reference, and a PWM comparator with latching logic. The accurate output LED current is achieved by an averaging current feedback loop .
The ZA8726H/ZA8756H also has multiple features to protect the controller from fault conditions, including Under Voltage Lockout (UVLO), Over Current Protection (OCP), and Over Voltage Protection (OVP). Additionally, to ensure the system reliability, the ZA8706B/ZA8706C is built with the thermal protection function (OTP).
ZA8726H & ZA8756H Features
■Non-Isolation LED driver
■SOP8 package
■Lower BOM Cost
■High Power Factor by One Cycle Control
■Lower THD Performance
■Accuracy Constant Current
■45kHz of fixed Frequency Control
■Gate Output Voltage Clamp
■LED Open Protection (OVP) with auto recovery
■LED Short Protection (SCP) with auto recovery
■Over Current Protection (OCP) with auto recovery
■Internal OTP Protection with auto recovery
ZA8726H & ZA8756H Application:E26/27, T8 LED Tube, Others LED Lighting Applications
Marking Information
Pin Configuration (Top View):
ZA8726H & ZA8756H Pin Description:
Pin No.
| Name | Function |
1 | I-SEN | Current Sense Pin, Connect to Sense |
2 | COMP | MOSFET Current Feedback Compensation Network |
3 | VCC | Power Supply Pin
|
4 | SOURCE | Source Pin of internal HV MOSFET and GND PIN
|
5,6,7,8 | DRAIN | Drain Pin of internal HV MOSFET
|
ZA8726H & ZA8756H Application Circuit:
ZA8726H & ZA8756H Function Block
ZA8726H & ZA8756H bulb lamp DEMO(AC input 90~264Vac,Output 48V 230mA)
The advantage of ZA8726H & ZA8756H summary
◆Support universal input voltage (90~264V) and linear adjustment rate! The output can becompatible with a power of 12 series ~24 on board, and the output current changes within 3%!
◆ high precision steady current, constant current accuracy of ± 1% (90~264 input changes)
◆ good batch consistency! After mass production batch verification, current accuracy can becontrolled within +/-3%! Because of the inductance current, output LED current is controlled byexternal components have little effect!
◆ high efficiency. The output of 18W, the highest efficiency up to 95%!
◆ open circuit, the output voltage can be clamped.
◆ The chip can drive 4A MOSFET (maximum power of 23W can be achieved)
◆ The circuit is very compact, BOM COST can be controlled within 3.5RMB (without EMC parts)
◆ The circuit can adopt general I-shaped inductance design, without the use of E type inductor,so the design of BOM lower cost.
Keywords: Zentel, ZA8726H,ZA8756H,Zentel,GL8911,GL8912,SD6901S,SD6902S,SD6904S,BP2325A,BP2326A,MT7832,MT7833,MT7834