Datasheet

LTC3608
3
3608fc
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Main Control Loop
SV
IN
Operating Input Voltage Range 4 18 V
I
Q
Input DC Supply Current
Normal
Shutdown Supply Current
900
15
2000
30
µA
µA
V
FB
Feedback Reference Voltage I
TH
= 1.2V, –40°C to 85°C (Note 3)
I
TH
= 1.2V, –40°C to 125°C (Note 3)
l
0.594
0.590
0.600
0.600
0.606
0.610
V
V
ΔV
FB(LINEREG)
Feedback Voltage Line Regulation V
IN
= 4V to 18V, I
TH
= 1.2V (Note 3) 0.002 %/V
ΔV
FB(LOADREG)
Feedback Voltage Load Regulation I
TH
= 0.5V to 1.9V (Note 3) –0.05 –0.3 %
I
FB
Feedback Input Current V
FB
= 0.6V –5 ±50 nA
g
m(EA)
Error Amplifier Transconductance I
TH
= 1.2V (Note 3)
l
1.4 1.7 2 mS
V
FCB
Forced Continuous Threshold
l
0.54 0.6 0.66 V
I
FCB
Forced Continuous Pin Current V
FCB
= 0.6V –1 –2 µA
t
ON
On-Time I
ON
= 60µA, V
ON
= 1.5V
I
ON
= 60µA, V
ON
= 0V
220 280
110
340 ns
ns
t
ON(MIN)
Minimum On-Time I
ON
= 180µA, V
ON
= 0V 60 100 ns
t
OFF(MIN)
Minimum Off-Time I
ON
= 30µA, V
ON
= 1.5V 320 500 ns
I
VALLEY(MAX)
Maximum Valley Current V
RNG
= 0.5V, V
FB
= 0.56V, FCB = 0V
V
RNG
= 0V, V
FB
= 0.56V, FCB = 0V
l
l
5
8
11
16
A
A
I
VALLEY(MIN)
Maximum Reverse Valley Current V
RNG
= 0.5V, V
FB
= 0.64V, FCB = 0V
V
RNG
= 0V, V
FB
= 0.64V, FCB = 0V
5.5
7.5
A
A
ΔV
FB(OV)
Output Overvoltage Fault Threshold 7 10 13 %
V
RUN/SS(ON)
RUN Pin Start Threshold
l
0.8 1.5 2 V
V
RUN/SS(LE)
RUN Pin Latchoff Enable Threshold RUN/SS Pin Rising 4 4.5 V
V
RUN/SS(LT)
RUN Pin Latchoff Threshold RUN/SS Pin Falling 3.5 4.2 V
I
RUN/SS(C)
Soft-Start Charge Current V
RUN/SS
= 0V –0.5 –1.2 –3 µA
I
RUN/SS(D)
Soft-Start Discharge Current V
RUN/SS
= 4.5V, V
FB
= 0V 0.8 1.8 3 µA
V
IN(UVLO)
Undervoltage Lockout INTV
CC
Falling
l
3.4 3.9 V
V
IN(UVLOR)
Undervoltage Lockout Release INTV
CC
Rising
l
3.5 4 V
R
DS(ON)
Top Switch On-Resistance
Bottom Switch On-Resistance
10
8
19
14
mΩ
mΩ
electrical characteristics
The l denotes the specifications which apply over the full operating
junction temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 15V unless otherwise noted.