NCP1421
http://onsemi.com
4
ELECTRICAL CHARACTERISTICS (V
OUT
= 3.3 V, T
A
= 25°C for typical value, −40°C T
A
85°C for min/max values unless
otherwise noted.)
Characteristic Symbol Min Typ Max Unit
Operating Voltage V
IN
1.0 − 5.0 V
Output Voltage Range V
OUT
1.5 − 5.0 V
Reference Voltage
(V
OUT
= 3.3 V, I
LOAD
= 0 A, C
REF
= 200 nF, T
A
= 25°C)
V
REF_NL
1.183 1.200 1.217 V
Reference Voltage
(V
OUT
= 3.3 V, I
LOAD
= 0 A, C
REF
= 200 nF, T
A
= −40°C to 85°C)
V
REF_NL
1.174 − 1.220 V
Reference Voltage Temperature Coefficient TC
VREF
− 0.03 − mV/°C
Reference Voltage Load Current
(V
OUT
= 3.3 V, V
REF
= V
REF_NL
1.5% C
REF
= 1.0 F) (Note 5)
I
REF
− 2.5 − mA
Reference Voltage Load Regulation
(V
OUT
= 3.3 V, I
LOAD
= 0 to 100 A, C
REF
= 1.0 F)
V
REF_LOAD
− 0.05 1.0 mV
Reference Voltage Line Regulation
(V
OUT
from 1.5 V to 5.0 V, C
REF
= 1.0 F)
V
REF_LINE
− 0.05 1.0 mV/V
FB Input Threshold (I
LOAD
= 0 mA, T
A
= 25°C) V
FB
1.192 1.200 1.208 V
FB Input Threshold (I
LOAD
= 0 mA, T
A
= −40°C to 85°C) V
FB
1.184 − 1.210 V
LBI Input Threshold (I
LOAD
= 0 mA, T
A
= −40C to 85C) V
LBI
1.162 1.230 V
LBI Input Threshold (T
A
= 25C) V
LBI
1.182 1.200 1.218 V
Internal NFET ON−Resistance R
DS(ON)_N
− 0.3 −
Internal PFET ON−Resistance R
DS(ON)_P
− 0.3 −
LX Switch Current Limit (N−FET) (Note 7) I
LIM
− 1.5 − A
Operating Current into BAT
(V
BAT
= 1.8 V, V
FB
= 1.8 V, V
LX
= 1.8 V, V
OUT
= 3.3 V)
I
QBAT
− 1.3 3 A
Operating Current into OUT (V
FB
= 1.4 V, V
OUT
= 3.3 V) I
Q
− 8.5 14 A
LX Switch MAX. ON−Time (V
FB
= 1.0 V, V
OUT
= 3.3 V, T
A
= 25C) t
ON
0.46 0.72 1.15 s
LX Switch MIN. OFF−Time (V
FB
= 1.0 V, V
OUT
= 3.3 V, T
A
= 25C) t
OFF
− 0.12 0.22 s
FB Input Current I
FB
− 1.0 50 nA
True−Cutoff Current into BAT
(LBI/EN = GND, V
OUT
= 0, V
IN
= 3.3 V, LX = 3.3 V)
I
BAT
− 50 − nA
BAT−to−LX Resistance (V
FB
= 1.4 V, V
OUT
= 3.3 V) (Note 7) R
BAT_LX
− 100 −
LBI/EN Input Current I
LBI
− 1.5 50 nA
LBO Low Output Voltage (V
LBI
= 0, I
SINK
= 1.0 mA) V
LBO_L
− − 0.2 V
Soft−Start Time (V
IN
= 2.5 V, V
OUT
= 5.0 V, C
REF
= 200 nF) (Note 6) T
SS
− 1.5 20 ms
EN Pin Shutdown Threshold (T
A
= 25°C) V
SHDN
0.35 0.5 0.67 V
Thermal Shutdown Temperature (Note 7) T
SHDN
− − 145 °C
Thermal Shutdown Hysteresis (Note 7) T
SDHYS
− 30 − °C
5. Loading capability increases with V
OUT.
6. Design guarantee, value depends on voltage at V
OUT.
7. Values are design guaranteed.
