LTC3834 Linear Technology, LTC3834 Datasheet - Page 4

• Manufacturer Part Number: LTC3834
• Description: Synchronous Step-Down Controller
• Manufacturer: Linear Technology

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LTC3834
TYPICAL PERFORMANCE CHARACTERISTICS
ELECTRICAL CHARACTERISTICS
SYMBOL
PGOOD Output
V
I
V
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 LTC3834E 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 LTC3834I is guaranteed to meet
performance specifi cations over the –40°C to 85°C operating temperature
range.
Note 3: T
dissipation P
4
temperature range, otherwise specifi cations are at T
PGOOD
PGL
PG
100
0.000001
90
80
70
60
40
20
10
50
30
LTC3834FE: T
LTC3834UFD: T
0
Effi ciency and Power Loss
vs Output Current
V
V
IN
OUT
J
is calculated from the ambient temperature T
= 12V
Burst Mode OPERATION
FORCED CONTINUOUS MODE
PULSE SKIPPING MODE
= 3.3V
D
according to the following formulas:
0.0001
PARAMETER
PGOOD Voltage Low
PGOOD Leakage Current
PGOOD Trip Level
OUTPUT CURRENT (A)
J
= T
J
= T
A
+ (P
A
+ (P
0.01
D
FIGURE 11 CIRCUIT
D
• 35°C/W)
• 37°C/W)
1
3834 G01
10000
1000
100
10
1
0.1
CONDITIONS
I
V
V
PGOOD
A
PGOOD
FB
V
V
and power
FB
FB
100
0.000001
with Respect to Set Regulated Voltage
90
80
70
60
40
50
A
Ramping Negative
Ramping Positive
= 2mA
Effi ciency vs Load Current
= 25°C. V
= 5V
V
OUT
The
V
V
= 3.3V
IN
IN
0.0001
= 12V
= 5V
OUTPUT CURRENT (A)
l
IN
denotes the specifi cations which apply over the full operating
= 12V, V
Note 4: The LTC3834 is tested in a feedback loop that servos V
specifi ed voltage and measures the resultant V
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 minimum on-time condition is specifi ed for an inductor
peak-to-peak ripple current ≥40% of I
Considerations in the Applications Information section).
0.01
FIGURE 11 CIRCUIT
RUN
= 5V unless otherwise noted.
T
1
A
3834 G02
= 25°C, unless otherwise noted.
98
96
94
92
88
86
84
80
90
82
0
Effi ciency vs Input Voltage
V
FIGURE 11 CIRCUIT
OUT
MAX
MIN
–12
5
8
= 3.3V
(see Minimum On-Time
10
INPUT VOLTAGE (V)
FB
15
.
TYP
–10
0.1
10
20
25
MAX
0.3
±1
–8
12
ITH
30
to a
35
UNITS
3834 G03
3834fb
μA
40
%
%
V