By Power Integrations 290


Power Integrations' LinkZero™-AX is an integrated offline switching IC that enables designers to achieve 0.00 Watts of standby energy consumption in auxiliary power supplies. LinkZero-AX features an innovative power-down mode that effectively turns off the auxiliary power supply when the end product is idle or in standby. Power-down mode is triggered by a signal accessible to a microcontroller, completely shutting down internal switch control circuits. However, while in this power-down mode, the BYPASS pin remains regulated, allowing the LinkZero-AX IC to be awakened with a reset pulse or button press.

When paired with CapZero™ and SENZero™, LinkZero-AX reduces standby power waste in high power products to as low as 5 mW, or effectively zero. Alternatively, while in power down mode, LinkZero-AX offers a simple means of providing up to 500 µA at 4 V from the regulated BYPASS pin. This current can be used to power a system wake up sensor while in power down mode while the rest of the system is in standby. This functionality, although increasing system standby power consumption, provides a simple means to power a low current sensor without requiring the power supply to switch.


  • Low system cost with zero standby consumption
    • Simple system configuration provides zero consumption standby/power down with user controlled wake up
    • Very tight IC parameter tolerances improves system manufacturing yield
    • Suitable for low-cost clampless designs
    • Frequency jittering greatly reduces EMI filter cost
    • Extended package creepage improves system field reliability
  • Advanced protection/safety features
    • Hysteretic thermal shutdown protection – automatic recovery reduces field returns
    • Universal input range allows worldwide operation
    • Auto-restart reduces delivered power by >85% during short-circuit and open loop fault conditions
    • Simple ON/OFF control, no loop compensation needed
    • High bandwidth provides fast turn on with no overshoot


  • Ultra low consumption standby and auxiliary supplies