High Performance Current Mode PWM Controller
OB2273 is a highly integrated current mode PWM control IC optimized for high performance, low standby power(less than 100mW) and cost effective offline flyback converter applications. It offers complete protection coverage with auto-recovery including Cycle-by-Cycle current limiting (OCP), over load protection (OLP), and VDD under voltage lockout (UVLO). It also provides the protections with latched shut down including over temperature protection (OTP), and over voltage (fixed or adjustable) protection (OVP).
Features:
◆ Power on Soft Start Reducing MOSFET Vds Stress
◆ Frequency shuffling for EMI
◆ Extended Burst Mode Control For Improved Efficiency and Minimum Standby Power Design
◆ Audio Noise Free Operation
◆ Fixed 65KHZ Switching Frequency
◆ Comprehensive Protection Coverage
VDD Under Voltage Lockout with Hysteresis (UVLO)
Cycle-by-cycle over current threshold setting for constant output power limiting over universal input voltage range
Overload Protection (OLP) with auto-recovery
Over Temperature Protection (OTP) with latch shut down
VDD Over voltage Protection(OVP) with latch shut down
Adjustable OVP through external Zener
◆ Available in SOT23-6 and DIP8 packages, RoHS compliant
Applications:
Offline AC/DC flyback converter for
◆ LED Monitor Power Supplier
◆ Netbook/Tablet PC Adapter
◆ Battery Charger
◆ Power Adapter
◆ Set-Top Box Power Supplies
◆ Open-frame SMPS
Typical Application:
M5573 can replace OB2273
The M5573 is a highly integrated current mode PWM controller designed for high performance, low standby power, low cost, high efficiency switching power supply systems.
The M5573 can operate in the skip cycle mode under no-load or light-load conditions, resulting in low standby power consumption and high conversion efficiency.
The M5573 requires only a small amount of current during startup and operation to reduce standby power consumption.
The M5573 includes a variety of protections including cycle-by-cycle current limit (OCP), VCC undervoltage protection, and overload protection (OLP). In addition: Overtemperature protection (OTP), (fixed or adjustable), VDD overvoltage protection (OVP) with self-recovery. The circuit has excellent EMI performance and eliminates audible noise below 20KHz. M5573 Features: Power-on soft-start reduces MOSFET's Vds pressure Improves EMI frequency jitter improves efficiency and standby power minimizes extended burst mode design no audio noise operation fixed 65KHz switching frequency cycle-by-cycle current limit (OCP) VCC undervoltage protection Auto-Recovery Overload Protection (OLP) Auto-Recovery Over-Temperature Protection (OTP) Auto-Recovery VDD Over-Voltage Protection (OVP) Adjustable OVP via External Zener, Package: SOT23-6
Teature
◆ Soft start function, reducing stress power MOSFET VDS
◆ Reduce EMI frequency jitter function
◆Improvement of skip cycle mode control to improve efficiency and reduce standby power consumption
◆ Minimum power backup power supply design
◆ Eliminate audio noise
◆65khz switching frequency
◆ Comprehensive protection performance
VDD undervoltage protection with hysteresis
Weekly overcurrent threshold setting, constant output power over the full voltage range
Overload protection (OLP) and automatic recovery
Automatically restored over temperature protection (OTP)
Automatically restored VDD overvoltage protection (OVP)
Adjustable OVP with external Zener diode overvoltage protection
Application areas:
Suitable for AC/DC flyback converters, mobile phone chargers, netbook chargers, notebook adapters, set-top box power supplies, various open switching power supplies, LED power supplies
Typical Application:
