LM2676
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
A
= T
J
= 25˚C. Unless otherwise specified V
IN
=12V for the 3.3V, 5V and Adjustable
versions and V
IN
=24V for the 12V version.
Symbol
I
Q
Parameter
Quiescent
Current
Conditions
Typ
Min
Max
Units
DEVICE PARAMETERS
V
FEEDBACK
= 8V
For 3.3V, 5.0V, and ADJ Versions
V
FEEDBACK
= 15V
For 12V Versions
I
STBY
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
ON/OFF Input = 0V
T Package, Junction to Ambient
T Package, Junction to Ambient
θ
JC
θ
JA
θ
JA
θ
JA
θ
JC
θ
JA
θ
JA
T Package, Junction to Case
S Package, Junction to Ambient
S Package, Junction to Ambient
S Package, Junction to Ambient
S Package, Junction to Case
SD Package, Junction to Ambient
SD Package, Junction to Ambient
29
2
55
˚C/W
++
26
35
2
56
˚C/W
45
V
IN
= 40V, ON/OFF Pin = 0V
V
SWITCH
= 0V
V
SWITCH
= −1V
I
SWITCH
= 3A
Measured at Switch Pin
Maximum Duty Cycle
Minimum Duty Cycle
I
BIAS
V
ON/OFF
V
FEEDBACK
= 1.3V
ADJ Version Only
ON/OFF Pin = 0V
50
4.5
3.8/3.6
100/150
5.25/5.4
200
15
0.17/0.29
225
280
µA
A
µA
mA
Ω
kHz
%
%
nA
4.2
6
mA
I
CL
I
L
16
0.15
260
91
0
85
R
DS(ON)
f
O
D
1.4
0.8
2.0
V
I
ON/OFF
θ
JA
θ
JA
20
65
45
µA
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