LTC3828
4
3828fc
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: T
J
is calculated from the ambient temperature T
A
and power
dissipation P
D
according to the following formulas:
LTC3828UH: T
J
= T
A
+ (P
D
• 34°C/W)
LTC3828G: T
J
= T
A
+ (P
D
• 95°C/W)
Note 3: The IC is tested in a feedback loop that servos V
ITH1, 2
to a
specifi ed voltage and measures the resultant V
OSENSE1, 2
.
Note 4: Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency. See Applications Information.
Note 5: Rise and fall times are measured using 10% and 90% levels. Delay
times are measured using 50% levels.
Note 6: The minimum on-time condition is specifi ed for an inductor
peak-to-peak ripple current ≥40% of I
MAX
(see minimum on-time
considerations in the Applications Information section).
Note 7: The LTC3828E is guaranteed to meet performance specifi cations
over the –40°C to 85°C operating temperature range as assured by design,
characterization and correlation with statistical process controls.
Note 8: This parameter is guaranteed by design.
TYPICAL PERFORMANCE CHARACTERISTICS
Effi ciency vs Output Current
and Mode (Figure 14)
Effi ciency vs Output Current
(Figure 14)
Effi ciency vs Input Voltage
(Figure 14)
OUTPUT CURRENT (A)
0.001
EFFICIENCY (%)
10
3828 G01
0.01
0.1
1
100
90
80
70
60
50
40
30
20
10
0
Burst Mode
OPERATION
FORCED
CONTINUOUS
MODE
CONSTANT
FREQUENCY
(BURST DISABLE)
V
IN
=15V
V
OUT
= 5V
f = 260kHz
OUTPUT CURRENT (A)
0.001 10
0.01
0.1
1
EFFICIENCY (%)
3828 G02
100
90
80
70
60
50
V
OUT
= 5V
f = 260kHz
V
IN
= 7V
V
IN
= 20V
V
IN
= 15V
INPUT VOLTAGE (V
5
EFFICIENCY (%)
100
90
80
70
60
50
25
3828 G03
10 15 20 30
V
OUT
= 5V
I
OUT
= 3A
f = 260kHz
T
A
= 25°C unless otherwise noted.
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
RUN1, 2
= 5V unless otherwise noted.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
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
with Respect to Set Output Voltage
V
OSENSE
Ramping Down
V
OSENSE
Ramping Up
–6
6
–7.5
7.5
–9.5
9.5
%
%
