iW1819 TM 18W AccuSwitch Quasi-Resonant PWM Controller with Integrated Power BJT for >5V Applications 1 Description The iW1819 integrates a high performance AC/DC power supply controller using digital control technology and a power BJT switch in one package to enable compact peak current mode PWM flyback power supplies. The device operates in quasi-resonant mode and features multiple key protection features, allowing designs with improved efficiency and lower EMI, while lowering the bill of material cost. The iW1819 features a distinctive soft-start scheme, which allows for fast and yet smooth start-up with both small and large capacitive loads. It removes the need for a secondary feedback circuit while achieving excellent line and load regulation. It also eliminates the need for loop compensation components while maintaining stability across all operating conditions. The pulse-by-pulse waveform analysis allows for fast dynamic load response. The built-in power limit function enables optimized transformer design for a wide input voltage range. Dialogs innovative, proprietary technology ensures that power supplies built with the iW1819 can achieve both the highest average efficiency and less than 30mW no-load power consumption. And, the iW1819 can start-up into a wide range of capacitive loads at voltages greater than 5V, making it ideal for networking, set-top box and home appliance power supply applications. For 5V applications, please see the iW1820. 2 Features Optimized for 12V/1.5A AC/DC adapters with Intrinsically low common mode noise < 30mW no-load power consumption at 230V and AC Optimized 72kHz maximum PWM switching fast dynamic response frequency achieves best size and efficiency TM AccuSwitch technology integrated 800V bipolar Adaptive multi-mode PWM/PFM control improves junction transistor (BJT) efficiency Adaptively controlled soft-start enables fast and Quasi-resonant operation for highest overall efficiency smooth start-up for a wide range of capacitive loads (from 330F to 6,000F) Dynamic base current control Very tight constant voltage and constant current No external loop compensation components required regulation over entire operating range Built-in single-point protections against output short- PrimAccurate primary-side feedback eliminates circuit, output low impedance, and output overvoltage optocoupler and simplifies design Built-in over-temperature protection (OTP) EZ-EMI design enhances manufacturability No audible noise over entire operating range 3 Applications Network power adapters for ADSL, wireless access AC/DC adaptor for set top box AC/DC power supplies for home appliances and industrial applications 26-Dec-2018 Product Summary Rev. 1.1 www.dialog-semiconductor.com 1 of 6 2018 Dialog Semiconductor3 iW1819 TM 18W AccuSwitch Quasi-Resonant PWM Controller with Integrated Power BJT for >5V Applications L N V OUT + + RTN 6 5 C C 7 E NC 4 GND GND 8 9 2 I V SENSE CC 10 V 1 ASU SENSE iW1819 Figure 3.1 : iW1819 Typical Application Circuit WARNING: The iW1819 is intended for high voltage AC/DC offline applications. Contact with live high voltage offline circuits or improper use of components may cause lethal or life threatening injuries or property damage. Only qualified professionals with safety training and proper precaution should operate with high voltage offline circuits. iW1819 Output Power Table at Universal Input (85V 264V ) AC AC 1 Condition Open Frame 2 18 Output Power (W) Notes: Note 1. Maximum practical continuous output power measured at open frame ambient temperature of 50C while minimum bulk capacitor voltage is kept above 90V (test unit is placed in a non-ventilated environment). Note 2. The output power can vary depending on the power supply system designs and operating conditions. 26-Dec-2018 Product Summary Rev. 1.1 www.dialog-semiconductor.com 2 of 6 2018 Dialog Semiconductor