LM2594/LM2594HV
LM2594/LM2594HV-ADJ
Electrical Characteristics
Specifications with standard type face are for T
J
= 25˚C, and those with
boldface type
apply over
full Operating Tempera-
ture Range
Symbol
Parameter
Conditions
LM2594/LM2594HV-ADJ
Typ
(Note 3)
SYSTEM PARAMETERS
(Note 5) Test Circuit
Figure 1
V
FB
Feedback Voltage
4.5V
≤
V
IN
≤
V
INmax
, 0.1A
≤
I
LOAD
≤
0.5A
V
OUT
programmed for 3V. Circuit of
Figure 1
η
Efficiency
V
IN
= 12V, I
LOAD
= 0.5A
80
1.230
1.193/1.180
1.267/1.280
V
V(min)
V(max)
%
Limit
(Note 4)
Units
(Limits)
All Output Voltage Versions
Electrical Characteristics
Specifications with standard type face are for T
J
= 25˚C, and those with
boldface type
apply over
full Operating Tempera-
ture Range
. Unless otherwise specified, V
IN
= 12V for the 3.3V, 5V, and Adjustable version and V
IN
= 24V for the 12V ver-
sion. I
LOAD
= 100 mA
Symbol
Parameter
Conditions
LM2594/LM2594HV-XX
Typ
(Note 3)
DEVICE PARAMETERS
I
b
f
O
Feedback Bias Current
Oscillator Frequency
Adjustable Version Only, VFB = 1.3V
(Note 6)
10
150
127/110
173/173
V
SAT
DC
I
CL
Saturation Voltage
Max Duty Cycle (ON)
Min Duty Cycle (OFF)
Current Limit
I
OUT
= 0.5A (Note 7) (Note 8)
(Note 8)
(Note 9)
Peak Current, (Note 7) (Note 8)
0.9
1.1/1.2
100
0
0.8
0.65/0.58
1.3/1.4
I
L
Output Leakage Current
(Note 7) (Note 9) (Note 10)
Output = 0V
2
15
I
Q
I
STBY
Quiescent Current
Standby Quiescent
Current
θ
JA
Thermal Resistance
(Note 9)
ON/OFF pin = 5V (OFF)
LM2594
LM2594HV
N Package, Junction to Ambient (Note 11)
M Package, Junction to Ambient (Note 11)
ON/OFF CONTROL
Test Circuit
Figure 1
ON /OFF Pin Logic Input
V
IH
V
IL
I
H
I
L
ON /OFF Pin
Input Current
V
LOGIC
= 0.5V (Regulator ON)
0.02
5
Threshold Voltage
Low (Regulator ON)
High (Regulator OFF)
V
LOGIC
= 2.5V (Regulator OFF)
5
15
1.3
0.6
2.0
V
V(max)
V(min)
µA
µA(max)
µA
µA(max)
140
95
150
(Note 10)
5
10
85
200/250
250/300
50
Output = −1V
A
A(min)
A(max)
µA(max)
mA
mA(max)
mA
mA(max)
µA
µA(max)
µA(max)
˚C/W
50/100
nA
kHz
kHz(min)
kHz(max)
V
V(max)
%
Limit
(Note 4)
Units
(Limits)
Note 1:
Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is in-
tended to be functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics.
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