Texas Instruments TPS7A78 LDO Linear Regulator enhances the overall efficiency and standby-power in power-supplies in a simple-to-use, non-magnetic approach to AC/DC conversion. The device employs a capacitor-drop architecture to reduce the AC source voltage before actively clamping the rectified voltage. The device then regulates this rectified voltage down to the application's particular operating voltage. The unique architecture of the device enables the standby power to be decreased to just a few 10s of milliwatts. The device's switched-capacitor stage reduces power losses by stepping down the rectified input voltage by a factor of four and extending the output-to-input current by the same ratio. Compared to a traditional capacitor-drop (cap-drop) stage, this step down decreases input current, thus reducing the value of the capacitance needed.
Electricity-metering applications, where the power supply needs to be reliable and magnetic tamper-proof, benefits from utilising the device because this product does not need external magnetics. This feature makes complying with IEC 61000-4-8 easier while reducing magnetic shielding cost. The device also comes with a user-programmable, power-fail detection threshold that can give an early alert to power failures and facilitate shutdown before complete power loss. The power-good indicator is also offered for sequencing or resetting a microcontroller.