SLVS028C - APRIL 1983 - REVISED AUGUST 1995
The TL77xxA family of monolithic integrated circuit supply voltage supervisors are specifically designed for use as reset controllers in microcomputer and microprocessor systems. The supply voltage supervisor monitors the supply for undervoltage conditions at the SENSE input. During power up, the RESET\ output becomes active (low) when VCC attains a value approaching 3.6 V. At this point (assuming that SENSE is above VIT+), the delay timer function activates a time delay after which outputs RESET\ and RESET go inactive (high and low respectively). When an undervoltage condition occurs during normal operation, outputs RESET\ and RESET go active. To ensure that a complete reset occurs, the reset outputs remain active for a time delay after the voltage at the SENSE input exceeds the positive-going threshold value. The time delay is determined by the value of the external capacitor CT: td = 1.3 x 104 x CT, where CT is in farads (F) and td is in seconds (s).
During power down (assuming that SENSE is below VIT-), the outputs remain active until the VCC falls below a maximum of 2 V. After this, the outputs are undefined.
An external capacitor (typically 0.1uF for the TL77xxAC and TL77xxAI and typically 0.02uF for the TL77xxAM) must be connected to REF to reduce the influence of fast transients in the supply voltage.
The TL77xxAC series are characterized for operation from 0°C to 70°C. The TL77xxAI series are characterized for operation from -40°C to 85°C. The TL7702AM and TL7705AM are characterized for operation over the full military range of -55°C to 125°C.
View more information about generic part numbers:TL7702A, TL7702AM, TL7705A, TL7705AM, TL7709A, TL7712A, TL7715A
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