LTC3707
4
3707fb
Effi ciency vs Output Current
(Figure 13)
Effi ciency vs Input Voltage
(Figure 13)
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
f
HIGH
Highest Frequency V
FREQSET
= 2.4V 280 310 360 kHz
I
FREQSET
FREQSET Input Current V
FREQSET
= 0V –2 –1 µA
3.3V Linear Regulator
V
3.3OUT
3.3V Regulator Output Voltage No Load
l
3.20 3.35 3.45 V
V
3.3IL
3.3V Regulator Load Regulation I
3.3
= 0 to 10mA 0.5 2 %
V
3.3VL
3.3V Regulator Line Regulation 6V < V
IN
< 30V 0.05 0.2 %
PGOOD Output
V
PGL
PGOOD Voltage Low I
PGOOD
= 2mA 0.1 0.3 V
I
PGOOD
PGOOD Leakage Current V
PGOOD
= 5V 1 µA
V
PG
PGOOD Trip Level, Either Controller V
OSENSE
Respect to Set Output Voltage
V
OSENSE
Ramping Negative
V
OSENSE
Ramping Positive
–6
6
–7.5
7.5
–9.5
9.5
%
%
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 LTC3707E is guaranteed to meet performance specifi cations
from 0°C to 85°C. Specifi cations over the – 40°C to 85°C operating
temperature range are assured by design, characterization and correlation
with statistical process controls. The LTC3707I is guaranteed to meet
performance specifi cations over the full – 40°C to 85°C operating
temperature range.
Note 3: T
J
is calculated from the ambient temperature T
A
and power
dissipation P
D
according to the following formula:
LTC3707EGN = T
J
= T
A
+ (P
D
• 85°C/W)
Note 4: The LTC3707 is tested in a feedback loop that servos V
ITH1, 2
to a
specifi ed voltage and measures the resultant V
OSENSE1, 2.
Note 5: Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency. See Applications Information.
Note 6: Rise and fall times are measured using 10% and 90% levels. Delay
times are measured using 50% levels.
Note 7: The IC minimum on-time is tested under an ideal condition
without external power FETs. It can be different when the IC is working in
an actual circuit. See Minimum On-Time Considerations in the Application
Information section.
Note 8: V
FREQSET
pin internally tied to a 1.19V reference through a
large resistance.
TYPICAL PERFORMANCE CHARACTERISTICS
Effi ciency vs Output Current
and Mode (Figure 13)
OUTPUT CURRENT (A)
0.001
0
EFFICIENCY (%)
10
30
40
50
100
70
0.01
0.1
1
3707 G01
20
80
90
60
10
FORCED
CONTINUOUS
MODE (PWM)
CONSTANT
FREQUENCY
(BURST DISABLE)
Burst Mode
OPERATION
V
IN
= 15V
V
OUT
= 5V
OUTPUT CURRENT (A)
0.001
EFFICIENCY (%)
70
80
10
3707 G02
60
50
0.01
0.1
1
100
90
V
IN
= 10V
V
IN
= 15V
V
IN
= 7V
V
IN
= 20V
V
IN
= 15V
V
OUT
= 5V
INPUT VOLTAGE (V)
5
EFFICIENCY (%)
70
80
3707 G03
60
50
15
25
30
100
V
OUT
= 5V
I
OUT
= 3A
90
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
= 15V, V
RUN/SS1, 2
= 5V unless otherwise noted.
