The TPS3818xxx family of microprocessor supervisory circuits
monitor system voltages from 0.4V to 5.0V,
asserting an open-drain RESET signal when
the SENSE voltage drops below a preset threshold or when the manual reset
(MR) pin drops to a logic low. The
RESET output remains low for the user-adjustable delay time after the SENSE voltage and manual reset (MR) return above the respective thresholds.
The TPS3818 uses a precision reference to achieve 0.5%
threshold accuracy for VIT ≤ 3.3V. The
reset delay time can be set to 20ms by disconnecting the CT pin, 300ms by
connecting the CT pin to VDD using a
resistor, or can be user-adjusted between 1.25ms and 10s by connecting the CT
pin to an external capacitor. When used with an external capacitor, the TPS3818xxx gives a more accurate delay time than the similar TPS3808xxx device. The TPS3818 has a very low typical quiescent
current of 2.4µA so it is well-suited to battery-powered applications.
It is available in either a small SOT23 and an ultra-small 2mm × 2mm QFN PowerPAD package, and is fully specified over a
temperature range of -40°C to +125°C (TJ).
The TPS3818xxx family of microprocessor supervisory circuits
monitor system voltages from 0.4V to 5.0V,
asserting an open-drain RESET signal when
the SENSE voltage drops below a preset threshold or when the manual reset
(MR) pin drops to a logic low. The
RESET output remains low for the user-adjustable delay time after the SENSE voltage and manual reset (MR) return above the respective thresholds.
The TPS3818 uses a precision reference to achieve 0.5%
threshold accuracy for VIT ≤ 3.3V. The
reset delay time can be set to 20ms by disconnecting the CT pin, 300ms by
connecting the CT pin to VDD using a
resistor, or can be user-adjusted between 1.25ms and 10s by connecting the CT
pin to an external capacitor. When used with an external capacitor, the TPS3818xxx gives a more accurate delay time than the similar TPS3808xxx device. The TPS3818 has a very low typical quiescent
current of 2.4µA so it is well-suited to battery-powered applications.
It is available in either a small SOT23 and an ultra-small 2mm × 2mm QFN PowerPAD package, and is fully specified over a
temperature range of -40°C to +125°C (TJ).