Datasheet

19
4251b12f
LTC4251B/LTC4251B-1/
LTC4251B-2
APPLICATIONS INFORMATION
Figure 10. Undervoltage Timing with an Overvoltage Glitch (All Waveforms are Referenced to V
EE
)
Figure 11. Overvoltage Timing (All Waveforms are Referenced to V
EE
)
132456789
V
UV/0V
DROPS BELOW V
OVLO
AND TIMER RESTARTS INITIAL TIMING CYCLE.
V
UV/0V
CLEARS V
UVHI
. CHECK TIMER < V
TMRL
, GATE < V
GATEL
AND SENSE < V
CB
.
V
UV/0V
OVERSHOOTS V
OVHI
AND TIMER ABORTS INITIAL TIMING CYCLE.
TIMER CLEARS V
TMRL
, CHECK GATE < V
GATEL
AND SENSE < V
CB
.
V
OVHI
V
UVHI
V
OVLO
V
TMRH
V
TMRL
V
ACL
V
CB
5.8μA
230μA
58μA
58μA
5.8μA
5.8μA
INITIAL TIMING CYCLE
START-UP CYCLE
4251b12 F10
UV/0V
TIMER
GATE
SENSE
10
1324567
UV/0V
TIMER
GATE
SENSE
V
OVHI
V
TMRH
V
OVLO
V
ACL
V
CB
5.8μA
5.8μA
5.8μA
5.8μA
4251b12 F11
230μA
58μA
58μA
V
UV/0V
DROPS BELOW V
OVLO
AND GATE RESTARTS.
V
UV/0V
OVERSHOOTS V
OVHI
AND GATE PULLS TO V
EE
. TIMER UNAFFECTED.