Datasheet

LTC3775
3
3775fa
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Input Supply
V
IN
V
IN
Supply Voltage
l
4.5 38 V
I
VIN
Input DC Supply Current V
FB
= 0.7V (Note 5)
V
RUN
= 0V
3.5
14
mA
µA
RUN/SHDN Pin
V
RUN
RUN/SHDN Pin Enable Threshold 1.19 1.22 1.25 V
V
SHDN
RUN/SHDN Pin Shutdown Threshold V
RUN/SHDN
Rising 0.74 V
V
SHDN(HYST)
RUN/SHDN Pin Shutdown Threshold Hysteresis 140 mV
I
RUN
RUN/SHDN Pin Source Current V
RUN/SHDN
= 0V
V
RUN/SHDN
= 1.5V
–1
–5
µA
µA
Error Amplifi er
V
FB
Feedback Pin Voltage
l
0.597
0.5955
0.600 0.603
0.6045
V
V
ΔV
FB
Feedback Voltage Line Regulation 4.5V < V
IN
< 38V ±0.01 %/V
ΔV
OUT
Output Voltage Load Regulation 1V < V
COMP
< 2V (Note 6) 0.01 0.1 %
I
FB
FB Pin Input Current V
FB
= 0.6V –50 50 nA
I
COMP
COMP Pin Output Current Sourcing, V
COMP
= 0V
Sinking, V
COMP
= 2V
–0.5
1
–1
60
mA
mA
f
0dB
Error Amplifi er Unity-Gain Crossover Frequency (Note 6) 25 MHz
Soft-Start
I
SS
SS Pin Source Current V
SS
= 0V –1 µA
R
SS
SS Pin Pull-Down Resistance in Current Limit 1.3 k
Current Limit
I
LIMB
I
LIMB
Source Current V
ILIMB
= 1V
l
–9 –10 –11 µA
I
LIMT
I
LIMT
Sink Current V
ILIMT
= 12V
l
90 100 110 µA
I
SENSE
SENSE Pin Input Current 1µA
V
ILIMT(MAX)
Topside Current Limit Threshold (V
IN
-SENSE) V
ILIMT
= 0.1V
l
90 100 110 mV
V
ILIMB(MAX)
Bottom Side Current Limit Threshold (PGND-SW) V
ILIMB
= 0.5V
l
80 100 120 mV
INTV
CC
Low Dropout Voltage Regulator
INTV
CC
LDO Regulator Output Voltage 4.9 5.2 5.5 V
ΔV
INTVCC(LINE)
INTV
CC
Line Regulation 7.5V < V
IN
< 38V 0.01 %/V
ΔV
INTVCC(LOAD)
INTV
CC
Load Regulation
ΔI
INTVCC
= 0mA to 20mA
–1 –0.1 %
V
DROPOUT
INTV
CC
Regulator Dropout Voltage (V
IN
– V
INTVCC
)I
INTVCC
= 20mA 0.35 V
V
UVLO
INTV
CC
UVLO Voltage INTV
CC
Rising
Hysteresis
3.0 3.6
0.5
4.2 V
V
The l denotes the specifi cations which apply over the full operating
junction temperature range, otherwise specifi cations are at T
A
= 25°C (Note 2). V
IN
= 12V, V
RUN
= 5V, unless otherwise specifi ed.