LTC3828_15 Datasheet, PDF (4/32 Pages) Linear Technology – Dual, 2-Phase Step-Down Controller with Tracking

LTC3828
ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications 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
I_PGOOD
V_PG
PGOOD Voltage Low
PGOOD Leakage Current
PGOOD Trip Level, Either Controller
I_PGOOD = 2mA
V_PGOOD = 5V
V_OSENSE with Respect to Set Output Voltage
V_OSENSE Ramping Down
V_OSENSE Ramping Up
0.1
0.3
V
±1
μA
–6
–7.5 –9.5
%
6
7.5
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: 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
specified 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 specified 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 specifications
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 T_A = 25°C unless otherwise noted.
Efficiency vs Output Current
and Mode (Figure 14)
100
Burst Mode
90 OPERATION
80
70
CONSTANT
FREQUENCY
60
(BURST DISABLE)
50
40
30
20
10
0
0.001
FORCED
CONTINUOUS
MODE
V_IN =15V
V_OUT = 5V
f = 260kHz
0.01
0.1
1
10
OUTPUT CURRENT (A)
3828 G01
Efficiency vs Output Current
(Figure 14)
100
V_IN = 7V
90
V_IN = 15V
80
70
60
50
0.001
V_IN = 20V
V_OUT = 5V
f = 260kHz
0.01
0.1
1
OUTPUT CURRENT (A)
10
3828 G02
Efficiency vs Input Voltage
(Figure 14)
100
90
80
70
60
V_OUT = 5V
I_OUT = 3A
f = 260kHz
50
5
10
15
20
25
30
INPUT VOLTAGE (V
3828 G03
3828fc
4