Description

The STRX6729 is a power IC for quasi-resonant type switching power supplies. It incorporates a power MOSFET and a controller IC, achieving high efficiency and low noise power supply systems. The STRX6729 is part of the STR-X6700 series, with the STR-W6700 series being the different package (TO-220F) versions.

Specifications and features

- Multi-Mode Control: The STRX6729 offers operation mode switching with three steps according to load conditions, achieving optimal high efficiency and low noise power supply systems across the full load range. Some functions may vary depending on the product.
- In Standby (Under Standby Load Conditions): The STRX6729 supports UVLO Intermittent Oscillation by low output voltage, which can be switched by Standby Signal or Auto Burst-Oscillation (switched automatically).
- Under Low to Middle Load Conditions: The STRX6729 utilizes Bottom-Skip Quasi-Resonant Operation (Bottom-Skip QR).
- Under Middle to Rating (or Heavy) Load Conditions: The STRX6729 employs Quasi-Resonant Operation (QR).
- Current-Mode Control
- Built-in PWM Oscillator: The PWM operates with a minimum frequency of around 22 kHz until the quasi-resonant signal becomes valid. This reduces the stress on components during startup and load-shorted conditions.
- Soft-Start Function
- Step-Drive Function: This function reduces switching noise.
- Built-in Maximum ON Time Limitation Circuit: This function limits the maximum ON time of the power MOSFET during transitions at low input voltage and power ON/OFF.
- Input Compensation at Overcurrent: This function reduces the distortion of the overcurrent operation point to AC input voltage change by adding three components.
- Built-in Avalanche Energy Guaranteed High-Voltage Power MOSFET
- Various Protections: The STRX6729 offers overcurrent protection (OCP) with pulse-by-pulse detection, overload protection (OLP) with latch shutdown, and overvoltage protection (OVP) with latch shutdown.

Application Scenarios

The STRX6729 is suitable for switching power supplies in various applications, including:

• Digital Consumer Equipment: LCD-TVs, PDP-TVs, CRT-TVs, etc.
• Home Appliances
• OA Equipments
• Industry Machines
• Communication Devices
• Others

Comparison

- High efficiency and low noise power supply systems

- Some functions may vary depending on the product