ver: 0.7 apr 09, 2012 tel: 886-3-5788833 http://www.gmt.com.tw 1 G660/g661/g662 global mixed-mode technology microprocessor reset ic features ? power-on reset generator with fixed delay time of 200ms ? manual reset input (G660/g661) ? available in three reset output options push-pull reset output (G660l/g662) push-pull reset output (G660h/g662) open-drain reset output (g661l) ? supply voltage supervision range 2.5v, 3v, 3.3v, 5v ? watchdog timer (G660/g661/g662) ? supply current of 10 a at v cc =3.3v ? sot-23-5 package ? temperature range . . . ? 40 c to 85 c applications ? critical p and c power monitoring ? industrial equipment ? programmable controls ? automotive systems ? portable/battery-powered equipment ? intelligent instruments ? wireless communications systems ? notebook/desktop computers general description the G660/g661/g662 provide circuits initialization and timing supervision, primarily for dsp and proces- sor-based systems. during power-on, reset (reset) is asserted when supply voltage vcc be- comes higher than 1.1 v. thereafter, the supply volt- age supervisor monitors vcc and keeps reset (reset) active as long as vcc remains below the threshold voltage v it+ (1) . an internal timer delays the return of the output to the inactive state to ensure proper system reset. the de- lay time, td, starts after vcc has risen above the threshold voltage v it+ . when the supply voltage drops below the threshold voltage v it- (2) , the outputs be- comes active again. no external components are re- quired. all the devices have a fixed-sense threshold voltage v it- set by an internal voltage divider. the G660/g661 incorporate a manual reset input, mr . a low level at mr causes reset (reset) to be- come active. the G660/g661/g662 have wdi pin. the watchdog timer is periodically triggered by a posi- tive or negative transition at wdi. when the supervis- ing system fails to retrigger the watchdog circuit within the time-out interval, t tout , reset (reset) becomes active for the time period td. this event also reinitial- izes the watchdog timer. leaving wdi unconnected disables the watchdog. the product spectrum is designed for supply voltages of 2.5v, 3v, 3.3v, and 5v. the circuits are available in a sot-23-5 package. note: (1) v it+ means the reset voltage of v cc from low to high (2) v it- means the reset voltage of v cc from high to low. pin configuration typical application circuit reset (reset) gnd sot-23-5 5 1 2 wdi 4 3 mr vcc ()is for G660h G660/g661 reset gnd sot-23-5 5 1 2 wdi 4 3 vcc reset g662 * mr is for G660/g661 ** reset i s for g662 p vcc reset i/o gnd 3.3v 100nf reset reset wdi gnd vcc G660/g661/ g662 reset mr * icc may increased at high t a , therefore, can not connect resistors to vcc to prevent icc abnormal behavior at high t a . reset (reset) gnd sot-23-5 5 1 2 wdi 4 3 mr vcc ()is for G660h G660/g661 reset gnd sot-23-5 5 1 2 wdi 4 3 vcc reset g662 * mr is for G660/g661 ** reset i s for g662 p vcc reset i/o gnd 3.3v 100nf reset reset wdi gnd vcc G660/g661/ g662 reset mr * p vcc reset i/o gnd 3.3v 100nf reset reset wdi gnd vcc G660/g661/ g662 reset mr * icc may increased at high t a , therefore, can not connect resistors to vcc to prevent icc abnormal behavior at high t a .
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