LM2594/LM2594HV-ADJ
Electrical Characteristics
=
Specifications with standard type face are for TJ 25˚C, and those with boldface type apply over full Operating Tempera-
ture Range
Symbol
Parameter
Conditions
LM2594/LM2594HV-ADJ
Units
(Limits)
Typ
Limit
(Note 3)
(Note 4)
SYSTEM PARAMETERS (Note 5) Test Circuit Figure 1
VFB
Feedback Voltage
4.5V ≤ VIN ≤ VINmax, 0.1A ≤ ILOAD ≤ 0.5A
1.230
80
V
VOUT programmed for 3V. Circuit of Figure 1
1.193/1.180
1.267/1.280
V(min)
V(max)
%
= =
VIN 12V, ILOAD 0.5A
η
Efficiency
All Output Voltage Versions
Electrical Characteristics
=
Specifications with standard type face are for TJ 25˚C, and those with boldface type apply over full Operating Tempera-
=
=
ture Range . Unless otherwise specified, VIN 12V for the 3.3V, 5V, and Adjustable version and VIN 24V for the 12V ver-
=
sion. ILOAD 100 mA
Symbol Parameter
Conditions
LM2594/LM2594HV-XX
Units
(Limits)
Typ
Limit
(Note 3)
(Note 4)
DEVICE PARAMETERS
=
Ib
Feedback Bias Current
Adjustable Version Only, VFB 1.3V
10
50/100
nA
kHz
fO
Oscillator Frequency
(Note 6)
150
127/110
173/173
kHz(min)
kHz(max)
V
=
VSAT
DC
Saturation Voltage
IOUT 0.5A (Note 7) (Note 8)
0.9
1.1/1.2
V(max)
%
Max Duty Cycle (ON)
Min Duty Cycle (OFF)
Current Limit
(Note 8)
100
0
(Note 9)
ICL
Peak Current, (Note 7) (Note 8)
0.8
A
0.65/0.58
1.3/1.4
50
A(min)
A(max)
µA(max)
mA
=
Output 0V
IL
Output Leakage Current
Quiescent Current
(Note 7) (Note 9) (Note 10)
=
Output −1V
2
5
15
10
mA(max)
mA
IQ
(Note 9)
mA(max)
µA
=
ISTBY
Standby Quiescent
Current
ON/OFF pin 5V (OFF)
(Note 10)
85
LM2594
200/250
250/300
µA(max)
µA(max)
˚C/W
LM2594HV
140
95
θJA
Thermal Resistance
N Package, Junction to Ambient (Note 11)
M Package, Junction to Ambient (Note 11)
150
ON/OFF CONTROL Test Circuit Figure 1
ON /OFF Pin Logic Input
1.3
V
VIH
VIL
IH
Threshold Voltage
Low (Regulator ON)
High (Regulator OFF)
0.6
2.0
V(max)
V(min)
µA
=
ON /OFF Pin
Input Current
VLOGIC 2.5V (Regulator OFF)
5
15
5
µA(max)
µA
=
IL
VLOGIC 0.5V (Regulator ON)
0.02
µA(max)
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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