lm2678sx-adj National Semiconductor Corporation, lm2678sx-adj Datasheet - Page 4

• Manufacturer Part Number: lm2678sx-adj
• Description: Simple Switcher High Efficiency 5a Step-down Voltage Regulator
• Manufacturer: National Semiconductor Corporation

www.national.com
Symbol
DEVICE PARAMETERS
I
I
I
I
R
f
D
I
V
I
θ
θ
θ
θ
θ
θ
θ
θ
θ
Q
STBY
CL
L
O
BIAS
ON/OFF
JA
JA
JC
JA
JA
JA
JC
JA
JA
All Output Voltage Versions
Electrical Characteristics
Limits appearing in bold type face apply over the entire junction temperature range of operation, −40˚C to 125˚C. Specifica-
tions appearing in normal type apply for T
versions and V
ON/OFF
Note 1: Absolute Maximum Ratings are limits beyond which damage to the device may occur. Operating Ratings indicate conditions under which of the device is
guaranteed. Operating Ratings do not imply guaranteed performance limits. For guaranteed performance limits and associated test condition, see the electrical
Characteristics tables.
Note 2: ESD was applied using the human-body model, a 100pF capacitor discharged through a 1.5 kΩ resistor into each pin.
Note 3: Typical values are determined with T
DS(ON)
Quiescent
Current
Standby
Quiescent
Current
Current Limit
Output Leakage
Current
Switch
On-Resistance
Oscillator
Frequency
Duty Cycle
Feedback Bias
Current
ON/OFF
Threshold
Voltage
ON/OFF Input
Current
Thermal
Resistance
Parameter
IN
=24V for the 12V version.
V
For 3.3V, 5.0V, and ADJ Versions
V
For 12V Versions
ON/OFF Pin = 0V
V
V
V
I
Measured at Switch Pin
Maximum Duty Cycle
Minimum Duty Cycle
V
ADJ Version Only
ON/OFF Input = 0V
T Package, Junction to Ambient
(Note 5)
T Package, Junction to Ambient
(Note 6)
T Package, Junction to Case
S Package, Junction to Ambient
(Note 7)
S Package, Junction to Ambient
(Note 8)
S Package, Junction to Ambient
(Note 9)
S Package, Junction to Case
SD Package, Junction to Ambient
(Note 10)
SD Package, Junction to Ambient
(Note 11)
SWITCH
FEEDBACK
FEEDBACK
IN
SWITCH
SWITCH
FEEDBACK
= 40V, ON/OFF Pin = 0V
A
= 5A
= T
= 0V
= −1V
J
= 8V
= 15V
= 1.3V
= 25˚C and represent the most likely norm.
A
= T
Conditions
J
= 25˚C. Unless otherwise specified V
4
0.12
Typ
260
4.2
1.4
50
16
91
85
20
65
45
56
35
26
55
29
7
0
2
2
IN
=12V for the 3.3V, 5V and Adjustable
6.1/5.75
Min
225
0.8
0.14/0.225
100/150
8.3/8.75
Max
200
280
2.0
15
45
6
Units
˚C/W
˚C/W
kHz
mA
mA
µA
µA
nA
µA
++
%
%
A
Ω
V