ver: 2.0 nov 23, 2012 tel: 886-3-5788833 http://www.gmt.com.tw 1 G680/g681 global mixed-mode technology microprocessor reset ic features ? 2.5% voltage threshold accuracy ? independently adjustable high- and low- voltage thresholds ? fully specified over temperature ? available in three output configurations push-pull reset output (G680l) push-pull reset output (G680h) open-drain reset output (g681l) ? 140ms min power-on reset pulse width ? 4 a supply current ? power supply transient immunity ? sot-23-5 packages applications ? computers ? controllers ? intelligent instruments ? critical p and c power monitoring ? portable / battery-powered equipment ? automotive general description the G680/g681 are microprocessor ( p) supervisory circuits used to monitor the power supplies in p and digital systems. high- and low- voltage thresholds can be adjusted independently, allowing for wide hystere- sis. voltage detection thresholds are accurate to 2%. these circuits perform a single function: they assert a reset signal whenever the v cc supply voltage declines below the low-voltage threshold, keeping it asserted for at least 140ms after v cc has risen above the high-voltage threshold. the g681l has an open-drain output stage, while the G680 have push-pull outputs. the g681l?s open-drain reset output requires a pull-up resistor that can be connected to a voltage higher than v cc . the G680l have an active-low reset output, while the G680h has an active-high reset output. the reset com- parator is designed to ignore fast transients on thresh- old input. the ic ? s power supply is separate from the detector inputs, allowing the G680/g681 to be powered from a down-stream supply. low supply current (4 a, typical) makes the G680/g681 ideal for use in portable equipment. the G680/g681 are available in sot -23-5 packages. ordering information order number (pb free/green) marking output type temp. range package G680lt1uf 680ax push-pull reset -40 c ~ +105 c sot-23-5 G680ht1uf 680bx push-pull r eset -40 c ~ +105 c sot-23-5 g681lt1uf 681ax open-drain reset -40 c ~ +105 c sot-23-5 note: t1: sot-23-5 pin configuration typical application circuit G680/g681 vcc reset(reset) sot-23-5 5 4 1 hth 2 3 gnd lth () is for G680h reset input gnd p v cc reset (reset) gnd G680/g681 v cc r pull-up v cc * *g681 only lth hth G680/g681 vcc reset(reset) sot-23-5 5 4 1 hth 2 3 gnd lth () is for G680h reset input gnd p v cc reset (reset) gnd G680/g681 v cc r pull-up v cc * *g681 only lth hth
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