STR-A6069H
High-performance PWM controller for flyback converters with integrated 650V MOSFET and advanced protection
Product Overview
Description
The STR-A6069H is a high-efficiency PWM controller designed for flyback converter applications.
It integrates a 650V power MOSFET and comprehensive protection features, minimizing external component count.
The controller supports quasi-resonant operation for improved efficiency and reduced EMI.
Product Series
STR
Primary Application
Mobile phone chargers
Key Features
- Integrated 650V/4A power MOSFET
- Quasi-resonant operation for high efficiency
- Low standby power consumption
- Frequency foldback at light load
- Built-in soft-start function
- Comprehensive protection (OVP, OCP, OTP)
- Auto-restart for fault recovery
- Pb-free and RoHS compliant
Specifications
| Topology | Flyback (Quasi-Resonant) |
|---|---|
| Integrated MOSFET | 650V, 4A |
| Maximum Power | Up to 30W |
| Operating Frequency | 65kHz (typical) |
| Standby Power | < 75mW at 230VAC |
| Efficiency | Meets DoE Level VI |
| Package | DIP-8, SOP-8 |
| Operating Temperature | -40°C to +125°C |
Applications
Mobile phone chargers
Battery and charging management
Power adapters
Electronic system design
Set-top box power supplies
Electronic system design
Small appliance power supplies
Electronic system design
LED driver power supplies
Motor drive and control systems
FAE Expert Insights
"The STR-A6069H is an excellent choice for compact power adapter designs up to 30W. The integrated MOSFET significantly reduces PCB space and component count. I particularly appreciate the quasi-resonant operation which provides excellent efficiency while keeping EMI low. The built-in protections are comprehensive and reliable. In my experience supporting numerous adapter designs, this controller consistently delivers stable performance. The low standby power easily meets modern efficiency standards. For designers creating compact chargers or adapters, this IC provides a cost-effective, high-performance solution."
Integrated MOSFET with quasi-resonant operation for high efficiency
— James Liu, BeiLuo
Frequently Asked Questions
What is the maximum output power of STR-A6069H?
The STR-A6069H supports up to 30W output power in typical flyback applications. The actual maximum power depends on the input voltage range, thermal design, and external component selection. For universal input (85-265VAC) applications, derating may be necessary at high line voltages. The integrated 4A MOSFET provides adequate margin for 30W operation with proper heat sinking.
For 30W applications, ensure proper thermal management. Contact us for thermal design guidelines.
How does the quasi-resonant operation work?
Quasi-resonant (QR) operation switches the MOSFET at the valley of the drain voltage ringing after the transformer demagnetization. This reduces switching losses and EMI by switching at minimum voltage. The STR-A6069H automatically detects the voltage valley and triggers the next switching cycle, optimizing efficiency across load variations. QR operation is particularly beneficial at high line voltages and provides better efficiency than fixed-frequency PWM.
QR operation improves efficiency automatically. No external configuration needed for valley detection.
What is the typical application circuit for STR-A6069H?
The typical application requires the STR-A6069H connected to the primary side of a flyback transformer. The drain pin connects to the transformer primary, source pin to current sense resistor. The feedback pin receives control signal from secondary side through optocoupler or auxiliary winding. External components include startup resistors, snubber circuit, and VCC capacitor. Reference schematics are available showing complete power supply designs.
Request reference designs from our team for your specific application. We provide complete schematics and BOMs.
How do I set the output voltage?
Output voltage is regulated through the feedback network on the secondary side. Use a TL431 shunt regulator or similar with resistor divider to set the desired output voltage. The feedback signal is coupled to the primary side through an optocoupler connected to the FB pin of STR-A6069H. The controller adjusts the switching to maintain the regulated output voltage. For multiple outputs, cross-regulation techniques may be needed.
Use standard TL431 feedback circuit. Contact us for feedback loop design guidance.
What transformer parameters are recommended?
Transformer design depends on output power, input voltage range, and switching frequency. For 30W applications, EE16 or EE19 cores are typically used. Primary inductance is calculated based on maximum power and minimum frequency. Turns ratio is determined by output voltage and diode drop. The transformer should be designed with appropriate core cross-section to avoid saturation. Starrystone Tech provides transformer design guidelines and can recommend qualified transformer suppliers.
Follow transformer design guidelines in the datasheet. Contact us for transformer supplier recommendations.
Does STR-A6069H meet energy efficiency standards?
Yes, STR-A6069H is designed to meet major energy efficiency standards including DoE Level VI (USA), CoC Tier 2 (Europe), and similar regulations. The low standby power (<75mW) and high active mode efficiency help achieve compliance. Actual efficiency depends on the complete power supply design including transformer, output rectifier, and filter components. Reference designs demonstrate compliance with these standards.
Follow reference designs for standard-compliant implementations. We can provide efficiency test data.