Datasheet

LTC3407-2
3
34072fc
ELECTRICAL CHARACTERISTICS
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 LTC3407E-2 is guaranteed to meet specifi ed performance
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. The LTC3407I-2 is guaranteed over the
full –40°C to 125°C operating temperature range.
The ● 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, unless otherwise specifi ed. (Note 2)
Note 3: The LTC3407-2 is tested in a proprietary test mode that connects
V
FB
to the output of the error amplifi er.
Note 4: Dynamic supply current is higher due to the internal gate charge
being delivered at the switching frequency.
Note 5: T
J
is calculated from the ambient T
A
and power dissipation P
D
according to the following formula: T
J
= T
A
+ (P
D
• θ
JA
).
Note 6: The DFN switch on-resistance is guaranteed by correlation to
wafer level measurements.
TYPICAL PERFORMANCE CHARACTERISTICS
Burst Mode Operation Pulse-Skipping Mode Load Step
T
A
= 25°C unless otherwise specifi ed.
34072 G01
V
IN
= 3.6V
V
OUT
= 1.8V
I
LOAD
= 100mA
CIRCUIT OF FIGURE 1
SW
5V/DIV
V
OUT
100mV/DIV
I
L
200mA/DIV
2μs/DIV
34072 G02
V
IN
= 3.6V
V
OUT
= 1.8V
I
LOAD
= 20mA
CIRCUIT OF FIGURE 1
SW
5V/DIV
V
OUT
10mV/DIV
I
L
200mA/DIV
1μs/DIV
3407 G03
V
IN
= 3.6V
V
OUT
= 1.8V
I
LOAD
= 80mA TO 800mA
CIRCUIT OF FIGURE 1
V
OUT
200mV/DIV
I
L
500mA/DIV
I
LOAD
500mA/DIV
20μs/DIV
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
FB
Feedback Voltage (Note 3) 0°C ≤ T
A
≤ 85°C
–40°C ≤ T
A
≤ 85°C
–40°C ≤ T
A
≤ 125°C (Note 2)
●
●
0.588
0.585
0.585
0.6
0.6
0.6
0.612
0.612
0.612
V
V
V
ΔV
LINE REG
Reference Voltage Line Regulation V
IN
= 2.5V to 5.5V (Note 3) 0.3 0.5 %/V
ΔV
LOAD REG
Output Voltage Load Regulation (Note 3) 0.5 %
I
S
Input DC Supply Current
Active Mode
Sleep Mode
Shutdown
(Note 4)
V
FB1
= V
FB2
= 0.5V
V
FB1
= V
FB2
= 0.63V, MODE/SYNC = 3.6V
RUN = 0V, V
IN
= 5.5V, MODE/SYNC = 0V
700
40
0.1
950
60
1
μA
μA
μA
f
OSC
Oscillator Frequency V
FBX
= 0.6V
●
1.8 2.25 2.7 MHz
f
SYNC
Synchronization Frequency 2.25 MHz
I
LIM
Peak Switch Current Limit V
IN
= 3V, V
FBX
= 0.5V, Duty Cycle <35% 0.95 1.2 1.6 A
R
DS(ON)
Top Switch On-Resistance
Bottom Switch On-Resistance
(Note 6)
(Note 6)
0.35
0.30
0.45
0.45
Ω
Ω
I
SW(LKG)
Switch Leakage Current V
IN
= 5V, V
RUN
= 0V, V
FBX
= 0V 0.01 1 μA
POR Power-On Reset Threshold V
FBX
Ramping Up, MODE/SYNC = 0V
V
FBX
Ramping Down, MODE/SYNC = 0V
8.5
–8.5
%
%
Power-On Reset On-Resistance 100 200 Ω
Power-On Reset Delay 262,144 Cycles
V
RUN
RUN Threshold
●
0.3 1 1.5 V
I
RUN
RUN Leakage Current
●
0.01 1 μA
V
MODE
Mode Threshold Low 0 0.5 V
Mode Threshold High V
IN
– 0.5 V
IN
V