iWatt Announces iW1700 Zero Power AC/DC Digital PWM Controller

iWatt, a provider of energy-efficient digital power supply control integrated circuits (ICs) used in leading-edge power supplies, announced the iW1700 Zero Power AC/DC Digital PWM Controller.

With the new controller, customers can benefit from low-cost, energy-efficient 120V/230VAC offline adapters and chargers (up to 5W) which consume zero no-load power for cell phones, audio players, digital cameras, and other low-power portable devices.

iWatt’s adaptive digital PWM/PFM technology sends the controller into sleep mode when the load is disconnected. It is designed to cut no-load power consumption to less than 4 mW, or effectively zero.

“Portable wall chargers with zero no-load power that hit the power supply sweet spot required design trade-offs, or a micro-controller and other components, until now. The iW1700 cuts wasted power to almost zero without costing an arm and a leg in special components,” said Zahid Rahim, vice president and general manager of iWatt’s AC/DC business unit, in a statement.

“Accurately measuring ultra low power is complicated because measurement instruments have a minimum resolution, and the standby load may be pulsed and/or draw asymmetric current,” Rahim added.

The iW1700 features primary-side control to eliminate an opto-coupler, quasi-resonant switching for low EMI, waveform analysis, and a high switching frequency to achieve no-load charger performance. The technology is expected to meet manufacturers’ power-supply requirements, and still enable a low bill-of-material cost.

The iW1700 removes no-load power waste without a relay switch or microcontroller using iWatt’s digital algorithms to switch between PWM and PFM modes multiple times as the end device charges. This approach eliminates audible noise, improves efficiency, and reduces switching losses by operating at a pre-determined minimum frequency at no-load.

Recently, MagmaR Design Automation, a provider of chip design software, announced iWatt adopted the TitanT platform to improve analog design and layout productivity, and to automate difficult routing tasks including analog cell layouts and chip-level assembly.