LM2678
Absolute Maximum Ratings
(Note 1)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Input Supply Voltage
ON/OFF Pin Voltage
Switch Voltage to Ground
Boost Pin Voltage
Feedback Pin Voltage
Power Dissipation
ESD (Note 2)
45V
−0.1V to 6V
−1V to V
IN
V
SW
+ 8V
−0.3V to 14V
Internally Limited
2 kV
Storage Temperature Range
Soldering Temperature
Wave
Infrared
Vapor Phase
−65˚C to 150˚C
4 sec, 260˚C
10 sec, 240˚C
75 sec, 219˚C
Operating Ratings
Supply Voltage
Junction Temperature Range (T
J
)
8V to 40V
−40˚C to 125˚C
Electrical Characteristics
LM2678-3.3
Symbol
V
OUT
η
Parameter
Output Voltage
Efficiency
Limits appearing in
bold type face
apply over the entire junction temperature
range of operation, −40˚C to 125˚C. Specifications appearing in normal type apply for T
A
= T
J
= 25˚C.
Conditions
V
IN
= 8V to 40V, 100mA
≤
I
OUT
≤
5A
V
IN
= 12V, I
LOAD
= 5A
Typical
(Note 3)
3.3
82
Min
(Note 4)
3.234/3.201
Max
(Note 4)
3.366/3.399
Units
V
%
LM2678-5.0
Symbol
V
OUT
η
Parameter
Output Voltage
Efficiency
Conditions
V
IN
= 8V to 40V, 100mA
≤
I
OUT
≤
5A
V
IN
= 12V, I
LOAD
= 5A
Typical
(Note 3)
5.0
84
Min
(Note 4)
4.900/4.850
Max
(Note 4)
5.100/5.150
V
%
Units
LM2678-12
Symbol
V
OUT
η
Parameter
Output Voltage
Efficiency
Conditions
V
IN
= 15V to 40V, 100mA
≤
I
OUT
≤
5A
V
IN
= 24V, I
LOAD
= 5A
Typical
(Note 3)
12
92
Min
(Note 4)
11.76/11.64
Max
(Note 4)
12.24/12.36
V
%
Units
LM2678-ADJ
Symbol
V
FB
η
Parameter
Feedback
Voltage
Efficiency
Conditions
V
IN
= 8V to 40V, 100mA
≤
I
OUT
≤
5A
V
OUT
Programmed for 5V
V
IN
= 12V, I
LOAD
= 5A
Typ
(Note 3)
1.21
84
Min
(Note 4)
1.186/1.174
Max
(Note 4)
1.234/1.246
V
%
Units
3
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