LT3570
ELECTRICAL CHARACTERISTICS
PARAMETER
Minimum Operating Voltage (V
IN1
)
Minimum Operating Voltage (V
IN2
)
Shutdown Current (Note 4)
V
IN1
Quiescent Current
V
IN2
Quiescent Current
V
IN3
Quiescent Current
Bias Quiescent Current
V
SHDN1,2,3
Pin Threshold
V
SHDN1,2,3
Pin UVLO
V
SHDNX
Pin Current
Switching Frequency
Maximum Duty Cycle
Synchronous Frequency Threshold
Synchronous Frequency Ratio, f
SYN
/f
OSC
Synchronous Frequency Minimum On/Off
Time
FB1,2,3 Pin Voltage
FB1,2,3 Pin Voltage Line Regulation
FB1,2 Pin Bias Current
FB3 Pin Bias Current
SS1,2 Pin Source Current
V
C1,2
Pin Source Current
V
C1,2
Pin Sink Current
SW1
Error Amplifier 1 Transconductance
Error Amplifier 1 Voltage Gain
V
C1
Pin Switching Threshold
V
C1
to SW1 Current Gain
SW1 Current Limit
SW1 V
CESAT
SW1 Leakage Current
(Note 7)
I
SW1
= 1A (Note 7)
SW1 = 40V, V
SHDN1
= 0V
1.5
190
100
750
5.9
2.4
240
0.2
5
3.1
μMho
V/V
mV
A/V
A
mV
μA
V
VIN1,2,3
= 2.5V to 40V, V
C1,2
= 1V
V
FB1,2
= 800mV, V
C1,2
= 1V (Note 6)
V
FB3
= 800mV (Note 6)
V
SS1,2
= 500mV
V
FB1,2
= 600mV
V
FB1,2
= 1V
l
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
IN1,2,3
= 12V, V
SHDN1,2,3
= 12V unless otherwise noted.
CONDITIONS
(Note 3)
(Note 3)
V
SHDN1,2,3
= 0V
V
SHDN1
= 12V, V
SHDN2,3
= 0V, V
C1
= 0.4V (Not Switching)
V
SHDN1
= 0V, V
SHDN2,3
= 12V
V
SHDN1,3
= 0V, V
SHDN2
= 12V, V
C2
= 0.4V (Not Switching)
V
SHDN1,3
= 12V, V
SHDN2
= 0V
V
SHDN1,2
= 0V, V
SHDN3
= 12V
V
SHDN1,2
= 12V, V
SHDN3
= 0V
V
BIAS
= 2.5V
I
VIN2
> 100μA
l
l
l
MIN
TYP
2.1
2.1
0
3.2
65
3.5
3.5
700
0
2.3
MAX
2.5
2.5
1.5
4.5
150
4.5
4.5
950
1.5
3.1
1.4
1.4
50
1.5
550
2300
UNITS
V
V
μA
mA
μA
mA
mA
μA
μA
mA
V
V
μA
μA
kHz
kHz
%
%
0.3
1.1
1.25
30
0.1
450
1900
95
80
0.3
500
2100
V
SHDNX
= 12V, V
SHDNY,Z
= 0V (Note 5)
V
SHDN1,2,3
= 0V
R
T
= 44.2k
R
T
= 7.87k
R
T
= 44.2k
R
T
= 7.87k
R
T
= 44.2k
R
T
= 7.87k
50
772
1.5
1.3
1.3
V
ns
788
0.01
30
30
4.5
12
12
200
200
804
mV
%/V
nA
nA
μA
μA
μA
3570fa
3
LINER [ LINEAR TECHNOLOGY ]
