ncp1578 ON Semiconductor, ncp1578 Datasheet - Page 15

• Manufacturer Part Number: ncp1578
• Description: Synchronous Step Down Controller With 50ma Linear Regulator
• Manufacturer: ON Semiconductor

EN_LDO
EN_LDO
PGOOD
VBAT > 6 V for
VBAT > 6 V for
EN_SW
LDO5 Soft-Start
PGDLY
PGOOD
EN_SW
LDO5 Ready
LDO5 Ready
SMPS
PGDLY
VOUT
LDO5
VBAT
SMPS
LDO5 Soft-Start
VOUT
LDO5
VBAT
Ready when LDO5 is
Maintain Logic Level
EN_SW Should Be
High Enough to
Ready when LDO5 is
Maintain Logic Level
EN_SW Should Be
High Enough to
Figure 32. Single V
Figure 33. Single V
LDO5 in Regulation
LDO5 in Regulation
SMPS Soft-Start
SMPS Soft-Start
BAT
BAT
TIMING DIAGRAMS
Configuration (SMPS Disabled by EN_LDO)
Configuration (SMPS Disabled by EN_SW)
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Regulation
Regulation
SMPS In
SMPS In
NCP1578
15
PGOOD Delay
and Goes High
PGOOD Delay
and Goes High
PGOOD Goes Low
when LDO5 Goes UVLO
Threshold
PGOOD Goes Low whenever
EN_SW Goes Low
V
on Output Loading
V
on Output Loading
PGOOD is Undermined
when LDO5 is too Low
to Maintain Logic Level
out
out
Drop Rate Depends
Drop Rate Depends