Datasheet

17
4251b12f
LTC4251B/LTC4251B-1/
LTC4251B-2
APPLICATIONS INFORMATION
Figure 7. System Power-Up Timing (All Waveforms are Referenced to V
EE
)
Figure 8. Power-Up Timing with a Short-Pin (All Waveforms are Referenced to V
EE
)
132456789
V
IN
CLEARS V
LKO
, CHECK V
UVHI
<UV/0V < V
OVLO
, TIMER< V
TMRL
, GATE < V
GATEL
AND SENSE < V
CB
.
TIMER CLEARS V
TMRL
, CHECK GATE < V
GATEL
AND SENSE < V
CB
.
GND-V
EE
UV/0V
V
IN
TIMER
GATE
SENSE
V
OUT
V
LKO
V
TMRH
V
TMRL
V
ACL
V
CB
5.8μA
5.8μA
5.8μA
INITIAL TIMING CYCLE
START-UP CYCLE
4251b12 F07
230μA
58μA
58μA
132456789
UV/0V CLEARS V
UVHI
, CHECK V
IN
< V
LKO
– V
LKH
, TIMER < V
TMRL
, GATE < V
GATEL
AND SENSE < V
CB
.
TIMER CLEARS V
TMRL
, CHECK GATE < V
GATEL
AND SENSE < V
CB
.
GND-V
EE
UV/0V
V
IN
TIMER
GATE
SENSE
V
OUT
V
UVHI
V
LKO
V
TMRH
V
TMRL
V
ACL
V
CB
5.8μA
5.8μA
5.8μA
INITIAL TIMING CYCLE START-UP CYCLE
4251b12 F08
230μA
58μA
58μA