LM2592HV
SIMPLE SWITCHER
Power Converter 150 kHz 2A
Step-Down Voltage Regulator
General Description
The LM2592HV series of regulators are monolithic inte-
grated circuits that provide all the active functions for a
step-down (buck) switching regulator, capable of driving a
2A load with excellent line and load regulation. These de-
vices are available in fixed output voltages of 3.3V, 5V, and
an adjustable output version.
This series of switching regulators is similar to the
LM2593HV, but without some of the supervisory and perfor-
mance features of the latter.
Requiring a minimum number of external components, these
regulators are simple to use and include internal frequency
compensation
, improved line and load specifications and a
fixed-frequency oscillator.
The LM2592HV operates at a switching frequency of 150
kHz thus allowing smaller sized filter components than what
would be needed with lower frequency switching regulators.
Available in a standard 5-lead TO-220 package with several
different lead bend options, and a 5-lead TO-263 Surface
mount package.
Other features include a guaranteed
4% tolerance on out-
put voltage under all conditions of input voltage and output
load conditions, and
15% on the oscillator frequency. Ex-
ternal shutdown is included, featuring typically 90 A
standby current. Self protection features include a two stage
current limit for the output switch and an over temperature
shutdown for complete protection under fault conditions.
Features
n
3.3V, 5V, and adjustable output versions
n
Adjustable version output voltage range, 1.2V to 57V
4% max over line and load conditions
n
Guaranteed 2A output load current
n
Available in 5-pin TO-220 and TO-263 (surface mount)
Package
n
Input voltage range up to 60V
n
150 kHz fixed frequency internal oscillator
n
On/Off control
n
Low power standby mode, I
Q
typically 90 A
n
High Efficiency
n
Thermal shutdown and current limit protection
Applications
n
Simple high-efficiency step-down (buck) regulator
n
Efficient pre-regulator for linear regulators
n
On-card switching regulators
n
Positive to Negative converter
Note:
Patent Number 5,382,918.
Typical Application
(Fixed Output Voltage Versions)
10129401
SIMPLE SWITCHER
and
Switchers Made Simple
are registered trademarks of National Semiconductor Corporation.
August 2001
LM2592HV
SIMPLE
SWITCHER
Power
Converter
150
kHz
2A
Step-Down
V
oltage
Regulator
2001 National Semiconductor Corporation
DS101294
www.national.com
Absolute Maximum Ratings
(Note 1)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Maximum Supply Voltage (V
IN
)
63V
ON/OFF Pin Voltage
-0.3
V
+25V
Feedback Pin Voltage
-0.3
V
+25V
Output Voltage to Ground
(Steady State)
-1V
Power Dissipation
Internally limited
Storage Temperature Range
-65C to +150C
ESD Susceptibility
Human Body Model (Note 2)
2 kV
Lead Temperature
S Package
Vapor Phase (60 sec.)
+215C
Infrared (10 sec.)
+245C
T Package (Soldering, 10 sec.)
+260C
Maximum Junction Temperature
+150C
Operating Conditions
Temperature Range
-40C
T
J
+125C
Supply Voltage
4.5V to 60V
LM2592HV-3.3
Electrical Characteristics
Specifications with standard type face are for T
J
= 25C, and those with boldface type apply over full Operating Tempera-
ture Range.
Symbol
Parameter
Conditions
LM2592HV-3.3
Units
(Limits)
Typ
Limit
(Note 3)
(Note 4)
SYSTEM PARAMETERS (Note 5) Test Circuit
Figure 1
V
OUT
Output Voltage
4.75V
V
IN
60V, 0.2A
I
LOAD
2A
3.3
V
3.168/3.135
V(min)
3.432/3.465
V(max)
Efficiency
V
IN
= 12V, I
LOAD
= 2A
76
LM2592HV-5.0
Electrical Characteristics
Specifications with standard type face are for T
J
= 25C, and those with boldface type apply over full Operating Tempera-
ture Range.
Symbol
Parameter
Conditions
LM2592HV-5.0
Units
(Limits)
Typ
Limit
(Note 3)
(Note 4)
SYSTEM PARAMETERS (Note 5) Test Circuit
Figure 1
V
OUT
Output Voltage
7V
V
IN
60V, 0.2A
I
LOAD
2A
5
V
4.800/4.750
V(min)
5.200/5.250
V(max)
Efficiency
V
IN
= 12V, I
LOAD
= 2A
81
%
LM2592HV-ADJ
Electrical Characteristics
Specifications with standard type face are for T
J
= 25C, and those with boldface type apply over full Operating Tempera-
ture Range.
Symbol
Parameter
Conditions
LM2592HV-ADJ
Units
(Limits)
Typ
Limit
(Note 3)
(Note 4)
SYSTEM PARAMETERS (Note 5) Test Circuit
Figure 1
V
FB
Feedback Voltage
4.5V
V
IN
60V, 0.2A
I
LOAD
2A
1.230
V
V
OUT
programmed for 3V. Circuit of
Figure 1.
1.193/1.180
V(min)
1.267/1.280
V(max)
Efficiency
V
IN
= 12V, V
OUT
= 3V, I
LOAD
= 2A
75
%
LM2592HV
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2
All Output Voltage Versions
Electrical Characteristics
Specifications with standard type face are for T
J
= 25C, 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. I
LOAD
= 500 mA
Symbol
Parameter
Conditions
LM2592HV-XX
Units
(Limits)
Typ
Limit
(Note 3)
(Note 4)
DEVICE PARAMETERS
I
b
Feedback Bias Current
Adjustable Version Only, V
FB
= 1.3V
10
nA
50/100
nA (max)
f
O
Oscillator Frequency
(Note 6)
150
kHz
127/110
kHz(min)
173/173
kHz(max)
V
SAT
Saturation Voltage
I
OUT
= 2A (Note 7) (Note 8)
1.10
V
1.3/1.4
V(max)
DC
Max Duty Cycle (ON)
(Note 8)
100
%
Min Duty Cycle (OFF)
(Note 9)
0
I
CLIM
Switch current Limit
Peak Current, (Note 7) (Note 8)
3.0
A
2.4/2.3
A(min)
3.7/4.0
A(max)
I
L
Output Leakage Current
(Note 7) (Note 9) (Note 10)
Output = 0V
50
A(max)
Output = -1V
5
mA
30
mA(max)
I
Q
Operating Quiescent
SD /SS Pin Open (Note 9)
5
mA
Current
10
mA(max)
I
STBY
Standby Quiescent
SD /SS pin = 0V
(Note 10)
90
A
Current
200/250
A(max)
JC
Thermal Resistance
TO220 or TO263 Package, Junction to Case
2
C/W
JA
TO220 Package, Juncton to Ambient (Note 11)
50
C/W
JA
TO263 Package, Juncton to Ambient (Note 12)
50
C/W
JA
TO263 Package, Juncton to Ambient (Note 13)
30
C/W
JA
TO263 Package, Juncton to Ambient (Note 14)
20
C/W
ON/OFF CONTROL Test Circuit
Figure 1
ON /OFF Pin Logic Input
1.3
V
V
IH
Threshold Voltage
Low (Regulator ON)
0.6
V(max)
V
IL
High (Regulator OFF)
2.0
V(min)
I
H
ON /OFF Pin Input Current
V
LOGIC
= 2.5V (Regulator OFF)
5
A
15
A(max)
I
L
V
LOGIC
= 0.5V (Regulator ON)
0.02
A
5
A(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
intended 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 25C 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%
production 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 can affect switching regulator system performance. When the
LM2592HV 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
overload.
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 to force the output transistor switch OFF.
Note 10: V
IN
= 60V.
LM2592HV
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3
All Output Voltage Versions
Electrical Characteristics
(Continued)
Note 11: Junction to ambient thermal resistance (no external heat sink) for the package mounted 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 sided 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 LM2592HVS side of the board, and approximately 16 in
2
of copper on the other side of the p-c board. See application hints in this data sheet and the thermal
model in Switchers Made Simple available at http://power.national.com.
LM2592HV
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4
Typical Performance Characteristics
(Circuit of
Figure 1)
Normalized
Output Voltage
Line Regulation
Efficiency
10129402
10129403
10129404
Switch Saturation
Voltage
Switch Current Limit
Dropout Voltage
10129405
10129406
10129407
Operating
Quiescent Current
Shutdown
Quiescent Current
Minimum Operating
Supply Voltage
10129408
10129409
10129410
LM2592HV
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