TPS3818

TPS3818 www.ti.com ......................................................................................................................................................... SBVS106A – MAY 2008 – REVISED AUGUST 2008 Low Quiescent Current, Accurate Programmable-Delay Supervisory Circuit FEATURES 1 23 Power-On Reset Generator with Adjustable Delay Time: 1.25ms to 10s Very Low Quiescent Current: 2.4µA typ High Threshold Accuracy: 0.5% typ Fixed Threshold Voltages for Standard Voltage Rails from 0.9V to 5V and Adjustable Voltage Down to 0.4V Are Available Manual Reset (MR) Input Open-Drain RESET Output Temperature Range: –40°C to +125°C Small SOT23 and 2mm × 2mm QFN Packages APPLICATIONS DSP or Microcontroller Applications Notebook/Desktop Computers PDAs/Hand-Held Products Portable/Battery-Powered Products FPGA/ASIC Applications 1.2V 3.3V DESCRIPTION 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 resist...