TL7705AI

TheTL7700Aseriesaremonolithicintegratedcircuit supplyvoltagesupervisorsspecificallydesi-gnedfor use as reset controllers in microcomputer and microprocessor systems. During power-up the device tests the supply voltage and keeps theRESET and RESET outputs active (high and low, respectively) as long as the supply voltage has not reached its nominal voltage value. Taking RESIN low has the same effect.To ensurethat themicrocomputersys-temhasreset, theTL7700Athen initiatesaninternal time delaythat delays the returnof the resetoutputs to their inactivestates.Since the timedelay formost microcomputers and microprocessorsis in theorder of several machine cycles, the device internal time delayis determinedby an external time delay is determined by an external capacitor connected to theC_T input (pin 3).

t_d = 1.3 x 10⁴xC_T

Where : C_T is in farads (F) and t_d in seconds (s). In addition, when the supply voltage drops below the nominal value, the outputs will be active until the supply voltage returns to the nominal value. An externalcapacitor(typically0.1µF)mustbeconnected to theREF output (pin 1) to reduce the influence of fast transients in the supply voltage.

The TL7700AI series is characterized for operation from 25^oC to 85^oC ; theTL7700ACseries is characterized from 0^oC to 70^oC.