TNY278PN IC – Power Integrations Off Line Switcher IC

The LNK306PN is specifically designed to replace all linear and capacitor-fed (cap dropper) non-isolated power supplies in the under 360 mA output current range at equal system cost while offering much higher performance and energy efficiency. LinkSwitch-TN devices integrate a 700 V power MOSFET, oscillator, simple On/Off control scheme, a high-voltage switched current source, frequency jittering, cycle-by-cycle current limit Figure 1. Typical Buck Converter Application (See Application Examples Section ? ?for Other Circuit Configurations).and thermal shutdown circuitry onto a monolithic IC. The start-up and operating power are derived directly from the voltage on the DRAIN pin, eliminating the need for a bias supply and associated circuitry in buck or fly back converters. The fully integrated auto-restart circuit in the LNK306 safely limits output power during fault conditions such as short-circuit or open loop, reducing component count and system-level load protection cost. ?A local supply provided by the IC allows use of a non-safety graded optocoupler acting as a level shifter to further enhance line and load regulation performance in buck and buck-boost converters.

The TNY279PN incorporates a 700 V power MOSFET, oscillator, high voltage switched current source, current limit (user selectable) and thermal shutdown circuitry. The IC family uses an ON/OFF control scheme and offers a design fl exible solution with a low system cost and extended power capability.

TNY288PG is also belongs to TinySwitch-4 Family from the manufacturer "Power Integrations". It is Energy-Efficient, Off-Line Switcher with Line Compensated Overload Power. It comes with following features:-

• Lowest System Cost with Enhanced Flexibility
  • 725 V rated MOSFET
  • Increases BV de-rating margin
  • Line compensated overload power ? no additional components
  • Dramatically reduces max overload variation over universal input voltage range
  • ?5% turn on UV threshold: line voltage sense with single external resistor
  • Simple ON/OFF control, no loop compensation needed
  • Selectable current limit through BP/M capacitor value
  • Higher current limit extends peak power or, in open frame applications, maximum continuous power
  • Lower current limit improves efficiency in enclosed adapters/ chargers
  • Allows optimum TinySwitch?-4 choice by swapping devices with no other circuit redesign
  • Tight I2 f parameter tolerance reduces system cost
    • Maximizes MOSFET and magnetics utilization
  • ON-time extension ? extends low-line regulation range/hold-up time to reduce input bulk capacitance
  • Self-biased: no bias winding or bias components
  • Frequency jittering reduces EMI filter costs
  • Pin-out simplifies heat sinking to the PCB
  • SOURCE pins are electrically quiet for low EMI

TOP250YN belongs to TOPSwitch-GX Family from the manufacturer "Power Integrations". It is with Extended Power, Design Flexiblity, EcoSmart & Integrated Off-line Switcher. TOPSwitch-GX uses the same proven topology as TOPSwitch, cost effectively integrating the high voltage power MOSFET, PWM control, fault protection and other control circuitry onto a single CMOS chip. Many new functions are integrated to reduce system cost and improve design flexibility, performance and energy efficiency. Depending on package type, either 1 or 3 additional pins over the TOPSwitch standard DRAIN, SOURCE and CONTROL terminals allow the following functions: line sensing (OV/UV, line feed-forward/DCMAX reduction), accurate externally set current limit, remote ON/OFF, synchronization to an external lower frequency, and frequency selection (132 kHz/66 kHz). All package types provide the following transparent features: Soft-start, 132 kHz switching frequency (automatically reduced at light load), frequency jittering for lower EMI, wider DCMAX, hysteretic thermal shutdown, and larger creepage packages. In addition, all critical parameters (i.e. current limit, frequency, PWM gain) have tighter temperature and absolute tolerances to simplify design and optimize system cost.