The TPS3899 is a nano-Iq, precision voltage supervisor that monitors system voltages or push-button inputs as low as 0.51 V. When the voltage of SENSE drops below the VIT- threshold, RESET/RESET will toggle after the programmed sense delay, set by CTS, has been reached. The TPS3899 asserts an open-drain or push-pull RESET/RESET signal to active-low logic (RESET) or active-high logic (RESET). The RESET/RESET output remains active until the SENSE voltage returns above the rising voltage threshold (VIT- + VHYS) for the reset delay set by CTR. The TPS3899 family uses a precision reference to achieve ±1% threshold accuracy. The sense delay and reset delay time can be user-adjusted by connecting a capacitor to the CTS and CTR pins respectively. The TPS3899 has a nano quiescent current of 125 nA (typ) and is available in a small 1.5-mm × 1.5-mm WSON package, making the device well-suited for battery-powered and space-constrained applications. The device is fully specified over a temperature range of –40°C to +125°C (TA).