The TNY284DG is an energy-efficient offline Switcher with line compensated overload power. TinySwitch-4 combines a high-voltage power MOSFET switch with a power supply controller in one device. Unlike conventional PWM controllers, it uses a simple ON/OFF control to regulate the output voltage. The controller consists of an oscillator and enables circuit (sense and logic), current limit state machine, 5.85V regulator, BYPASS/MULTIFUNCTION pin undervoltage, overvoltage circuit and current limit selection circuitry, over-temperature protection, current limit circuit, leading edge blanking and a 725V power MOSFET. TinySwitch-4 incorporates additional circuitry for line undervoltage sense, auto-restart, adaptive switching cycle on-time extension and frequency jitter. The drain pin is the power MOSFET drain connection. It provides internal operating current for both start-up and steady-state operation.
● Line compensated overload power - No additional components
● Dramatically reduces max overload variation over universal input voltage range
● Simple ON/OFF control, no loop compensation needed
● Selectable current limit through BP/M capacitor value
● Higher current limit extends peak power/in open frame, maximum continuous power
● Allows optimum TinySwitch-4 choice by swapping devices with no other circuit redesign
● Maximizes MOSFET and magnetic 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
● Pin-out simplifies heat sinking to the PCB
● SOURCE pins are electrically quiet for low EMI
● Accurate hysteretic thermal shutdown protection with automatic recovery eliminates need for reset
● Output overvoltage shutdown with optional Zener
● Fast AC reset with optional UV external resistor
● Very low component count enhances reliability and enables single-sided printed circuit board layout
● High bandwidth provides fast turn-ON with no overshoot and excellent transient load response
● Extended creepage between DRAIN and all other pins improves field reliability
● Easily meets all global energy efficiency regulations
● ON/OFF control provides constant efficiency down to very light loads
