LDO regulators reduce power in wearables, IoT devices

October 16, 2016 // By Nick Flaherty
SII Semiconductor, part of Seiko Instruments, is launching a series of LDO regulators with a power monitor to simplify the design of wearable and IoT devices.

The S-174x Series is the industry’s first LDO regulator to use the power monitor output function, which divides the battery voltage of the input to the LDO regulator, by half or one-third, and outputs the divided voltage for power monitoring.

The power monitoring output voltage is connected to the A/D converter of a low-voltage microcontroller, making it possible to monitor the battery voltage via the input voltage of the regulator. This eliminates the need for external resistors used in conventional systems to divide the voltage for battery monitoring. This new series also features an ultra-low current consumption of 0.5μA, helping to reduce power consumption of wearable and IoT devices and extend battery life.

The power monitoring output is an analog output, which allows users to set multiple threshold values for battery voltage monitoring on the microcontroller side. This allows the user to turn off the communication function and record data logs only when the battery voltage falls to a specified level. When the voltage drops further, the user can switch the device to standby mode and stop power consumption to prevent system malfunction.

The S-174x Series of LDO regulators is available in HSNT-6 (1.2×1.2×0.4mm) and HSNT-4 (1.0×1.0×0.4mm) packaging for thinner wearable and IoT devices. The SOT-23-5 (2.8×2.9×1.3mm) package is also an option.

The data sheet is at http://datasheet.sii-ic.com/en/voltage_regulator/S1740_1741_E.pdf and www.sii-ic.com/en/