Features
- Meets proposed mandatory federal efficiency standards for external power supplies
- Intrinsically low noise solution - No audible noise over the entire operating range
- Easily meets Energy Star® AC/DC power supply efficiency specs (Rev. 2.0)
- Less than 20mW no-load power consumption
- Low 1.7µA start-up current
- Active start-up circuit to reduce turn-on time
- 72kHz PWM switching frequency
- Voltage offset compensation for voltage loss in cables and connectors (4 options)
- PrimAccurate™ - Primary-side control, no optocoupler needed
- Quasi-resonant control for optimal efficiency
- EZ-EMI™ design to easily meet global EMI specifications
- Fast dynamic load regulation
- Fully protected from fault conditions
- Over-temperature protection
- Output overvoltage and overcurrent
- Input undervoltage protection
- Sense-resistor short circuit protection
Description
The iW1677 is a high-performance AC/DC controller designed to drive a low-cost bipolar junction transistor (BJT) power switch in peak current mode PWM flyback power supplies up to 5W. Ideal for power adapters for smartphones, the iW1677 integrates Renesas' PrimAccurate™ digital primary-side control, eliminating the need for the secondary-side optocoupler, and reducing component count and solution cost.
The iW1677 integrates an active start-up circuit that allows for fast turn-on without impacting operating current consumption. The device easily meets the US DoE’s external power supply standard and the EU’s Code of Conduct, Version 5, Tier 2 standard, with a no-load power consumption of less than 20mW. Additional features include Renesas' proprietary EZ-EMI™ technology, quasi-resonant control for optimal efficiency at heavy loads, cable and connector voltage drop compensation options, full protection from fault conditions, and tiny packaging.
Parameters
| Attributes | Value |
|---|---|
| Topology Characteristic | Flyback |
| Control Mode | Primary-Side Regulation Peak Current Mode DCM |
| UVLO Rising (V) | 11 |
| UVLO Falling (V) | 4 |
| VBIAS (Max) (V) | 16 |
| PWMs (#) | 1 |
| Output Power Max (W) | 5 |
| Switching Frequency (KHz) | 72 - 72 |
| No Load Power (mW) | 20 |
| Controller / Integrated | Controller |
| Advanced Features | EZ-EMI, PrimAccurate |
| Temp. Range (°C) | -40 to +125°C |
| Qualification Level | Standard |
Package Options
| Pkg. Type | Lead Count (#) | Pitch (mm) |
|---|---|---|
| SOT23-6L | 6 | 0.95 |
Applications
- Power adapters for portable electronics
- Consumer electronics power supplies
- Linear AC/DC power supply replacement