All Output Voltage Versions
Electrical Characteristics
(Continued)
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
= 200 mA.
Symbol
Parameter
Conditions
LM2595-XX
Typ
(Note 3)
ON/OFF CONTROL
Test Circuit
Figure 1
I
H
I
L
ON/OFF Pin
Input Current
V
LOGIC
= 2.5V (Regulator OFF)
V
LOGIC
= 0.5V (Regulator ON)
5
15
0.02
5
µA
µA(max)
µA
µA(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.
Note 2:
The human body model is a 100 pF capacitor discharged through a 1.5k resistor into each pin.
Note 3:
Typical numbers are at 25˚C and represent the most likely norm.
Note 4:
All limits guaranteed at room temperature (standard type face) and at temperature extremes (bold type face). All room temperature limits are 100% produc-
tion tested. All limits at temperature extremes are guaranteed via correlation using standard Statistical Quality Control (SQC) methods. All limits are used to calculate
Average Outgoing Quality Level (AOQL).
Note 5:
External components such as the catch diode, inductor, input and output capacitors, and voltage programming resistors can affect switching regulator sys-
tem performance. When the LM2595 is used as shown in the
Figure 1
test circuit, system performance will be as shown in system parameters section of Electrical
Characteristics.
Note 6:
The switching frequency is reduced when the second stage current limit is activated. The amount of reduction is determined by the severity of current over-
load.
Note 7:
No diode, inductor or capacitor connected to output pin.
Note 8:
Feedback pin removed from output and connected to 0V to force the output transistor switch ON.
Note 9:
Feedback pin removed from output and connected to 12V for the 3.3V, 5V, and the ADJ. version, and 15V for the 12V version, to force the output transistor
switch OFF.
Note 10:
V
IN
= 40V.
Note 11:
Junction to ambient thermal resistance (no external heat sink) for the TO-220 package mounted vertically, with the leads soldered to a printed circuit board
with (1 oz.) copper area of approximately 1 in
2
.
Note 12:
Junction to ambient thermal resistance with the TO-263 package tab soldered to a single printed circuit board with 0.5 in
2
of (1 oz.) copper area.
Note 13:
Junction to ambient thermal resistance with the TO-263 package tab soldered to a single sided printed circuit board with 2.5 in
2
of (1 oz.) copper area.
Note 14:
Junction to ambient thermal resistance with the TO-263 package tab soldered to a double sided printed circuit board with 3 in
2
of (1 oz.) copper area on
the LM2595S side of the board, and approximately 16 in
2
of copper on the other side of the p-c board. See Application Information in this data sheet and the thermal
model in
Switchers Made Simple
®
version 4.3 software.
Typical Performance Characteristics
Normalized
Output Voltage
Line Regulation
(Circuit of
Figure 1)
Efficiency
DS012565-12
DS012565-11
DS012565-13
5
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