Datasheet Maxim MAX809MEXR+T — 数据表

MAX803/MAX809/ MAX810 3-Pin Microprocessor Reset Circuits General Description The MAX803/MAX809/MAX810 are microprocessor (P) supervisory circuits used to monitor the power supplies in P and digital systems. They provide excellent circuit reliability and low cost by eliminating external components and adjustments when used with +5V, +3.3V, +3.0V, or +2.5V powered circuits. These circuits perform a single function: they assert a reset signal whenever the VCC supply voltage declines below a preset threshold, keeping it asserted for at least 140ms after VCC has risen above the reset threshold. Reset thresholds suitable for operation with a variety of supply voltages are available. The MAX803 has an open-drain output stage, while the MAX809/MAX810 have push-pull outputs. The MAX803's open-drain RESET output requires a pullup resistor that can be connected to a voltage higher than VCC. The MAX803/MAX809 have an active-low RESET output, while the MAX810 has an active-high RESET output. The reset comparator is designed to ignore fast transients on VCC, and the outputs are guaranteed to be in the correct logic state for VCC down to 1V. Low supply current makes the MAX803/MAX809/MAX810 ideal for use in portable equipment. The MAX803 is available in a 3-pin SC70 package, and the MAX809/ MAX810 are available in 3-pin SC70 or SOT23 packages. Benefits and Features Precision Monitoring of +2.5V, +3V, +3.3V, and +5V Power-Supply Voltages Fully Specified Over Temperature Available in Three Output Configurations Open-Drain RESET Output (MAX803) Push-Pull RESET Output (MAX809) Push-Pull RESET Output (MAX810) 140ms (min) Power-On-Reset Pulse Width 12A Supply Current Guaranteed Reset Valid to VCC = +1V Power Supply Transient Immunity No External Components 3-Pin SC70 and SOT23 Packages Selector Guide and Ordering Information appear at end of data sheet. Typical Operating Circuit
VCC VCC VCC RPULLUP* MAX803 MAX809
RESET µP
RESET INPUT Applications Computers Controllers Intelligent Instruments Critical P and C Power Monitoring Portable/Battery-Powered Equipment Automotive GND GND *MAX803 ONLY 19-0344; Rev 10; 12/15 MAX803/MAX809/ MAX810
Absolute Maximum Ratings
Terminal Voltage (with respect to GND) VCC .-0.3V to +6.0V RESET, RESET (push-pull) . -0.3V to (VCC + 0.3V) RESET (open drain) .-0.3V to +6.0V Input Current, VCC .20mA Output Current, RESET, RESET .20mA Rate of Rise, VCC .100V/s 3-Pin Microprocessor Reset Circuits Continuous Power Dissipation (TA = +70°C) 3-Pin SC70 (derate 2.17mW/°C above +70°C) .174mW 3-Pin SOT23 (derate 4mW/°C above +70°C) .320mW Operating Temperatu …