IW1812 Datasheet, PDF (1/17 Pages) Dialog Semiconductor – Off-Line Digital Green-Mode PWM Controller Integrated with Power BJT and OTP

iW1812
Off-Line Digital Green-Mode PWM Controller
Integrated with Power BJT and OTP
1 Description
The iW1812 is a high performance AC/DC power supply control device which uses digital control technology to build
peak current mode PWM flyback power supplies. This device includes an internal power BJT and operates in quasi-
resonant mode to provide high efficiency along with a number of key built-in protection features while minimizing the
external component count, simplifying EMI design, and lowering the total bill of material cost. The iW1812 removes the
need for secondary feedback circuitry while achieving excellent line and load regulation. It also eliminates the need for
loop compensation components while maintaining stability in all operating conditions. The pulse-by-pulse waveform
analysis allows for a loop response that is much faster than traditional solutions, resulting in improved dynamic load
response for both one-time and repetitive load transients. The built-in power limit function enables optimized transformer
design in universal off-line applications and allows for a wide input voltage range.
Dialog’s innovative proprietary technology ensures that power supplies built with the iW1812 can achieve both highest
average efficiency and less than 30mW no-load power consumption in a compact form factor.
2 Features
●● Primary-side feedback eliminates opto-isolators and
simplifies design
●● Internal 800V bipolar junction transistor (BJT)
●● 64kHz PWM switching frequency
●● No-load power consumption < 30mW at 230V_AC with
typical application circuit
●● Fast dynamic load response for both one-time and
repetitive load transients
●● Adaptive multi-mode PWM/PFM control improving
efficiency
●● Quasi-resonant operation for highest overall
efficiency
●● Ultra-low start-up current (1.7μA typical)
●● EZ-EMI^® design to easily meet global EMI standards
●● Dynamic BJT base drive current control
●● Very tight constant voltage and constant current
regulation with primary-side-only feedback
●● No external compensation components required
●● Complies with EPA 2.0 energy-efficiency
specifications with ample margin
●● Built-in soft start
●● Built-in short-circuit protection and output over-voltage
protection
●● Built-in current-sense-resistor short-circuit protection
●● Built-in over-temperature protection (OTP)
●● No audible noise over entire operating range
3 Applications
●● Low-power AC/DC power supply for smart meters,
motor control, industrial, and home appliances
applications
●● Linear AC/DC replacement
Datasheet
www.dialog-semiconductor.com
Rev. 1.2
1 of 17
26-September-2016
© 2016 Dialog Semiconductor