Datasheet

LTC3454
3
3454fa
ELECTRICAL CHARACTERISTICS
The l denotes the specifi cations which apply over the full operating
temperature range, otherwise specifi cations are at T
A
= 25°C. V
IN
= 3.6V, R
ISET
= 20.5k unless otherwise noted. (Note 2)
PARAMETER CONDITIONS MIN TYP MAX UNITS
Oscillator Frequency 0.9 1.0 1.15 MHz
Soft-Start Time 200 μs
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: The LTC3454 is guaranteed to meet specifi cations from 0°C to
70°C. Specifi cations over the – 40°C to 85°C operating temperature range
are assured by design, characterization and correlation with statistical
process controls.
Note 3: T
J
is calculated from the ambient temperature T
A
and power
dissipation PD according to the following formula:
T
J
= T
A
+ (PD • θ
JA
°C/W).
Note 4: Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency.
Note 5: This parameter is tested using a feedback loop which servos V
C
to 1.8V.
TYPICAL PERFORMANCE CHARACTERISTICS
Undervoltage Lockout Threshold
vs Temperature
Enable Thresholds
vs Temperature
Enable Thresholds vs V
IN
I
SET1,2
Servo Voltage
vs Temperature
I
SET1,2
Servo Voltage vs V
IN
I
SET1,2
Servo Voltage vs R
ISET
TEMPERATURE (°C)
–55
1.4
UVLO THRESHOLD (V)
1.5
1.7
1.8
1.9
2.4
2.1
–15
25
45 125
3454 G01
1.6
2.2
2.3
2.0
–35 5
65
85
105
V
IN
RISING
V
IN
FALLING
TEMPERATURE (°C)
–55
200
ENABLE THRESHOLDS (mV)
300
500
600
700
1200
900
–15
25
45 125
3454 G02
400
1000
1100
800
–35 5
65
85
105
V
IH
V
IL
V
IN
= 3.6V
V
IN
(V)
2.7
200
ENABLE THRESHOLDS (mV)
300
500
600
700
1200
900
3.5 5.5
3454 G03
400
1000
1100
800
3.1 3.9
4.3
4.7
5.1
V
IH
T
A
= 25°C
V
IL
TEMPERATURE (°C)
–55
788
V
ISET1,2
(mV)
792
800
804
808
–15
25
45 125
3454 G04
796
–35 5
65
85
105
812
V
IN
= 3.6V
R
ISET1,2
= 15k
V
IN
(V)
2.7
V
ISET1,2
(mV)
804
808
812
3.9 4.7
3454 G05
800
796
3.1 3.5
4.3 5.1 5.5
792
788
T
A
= 25°C
R
ISET1
= R
ISET2
= 15k
R
ISET
(kΩ)
3
V
ISET1,2
(mV)
804
808
812
15 23
3454 G06
800
796
711
19 27 31
792
788
V
IN
= 3.6V
T
A
= 25°C