3A, 52kHz, Step-down Switching Regulator
FEATURES
Step-down Switching Regulator
Adjustable Version Output Voltage Range, 1.23V to 52V
± 4% Max over Line and Load conditions
Guaranteed Output Current of 3A
Fixed Output Voltages : 3.3V, 5.0V, 12V and 15V
Wide Input Voltage Range 60V
52 kHz Fixed Frequency Oscillator
TTL Shutdown Capability, Low Power Standby Mode
Requires only 4 External Components
High Efficiency
Use Readily Available Standard Inductors
Available in TO-220, TO-263 and SOP-8PP Packages
Thermal Shutdown and Current Limit Protection
Moisture Sensitivity Level 3
LM2576HV
SOP-8PP PKG
TO-263 PKG
TO-220 PKG
APPLICATION
Simple high-efficiency step-down (buck) regulator
Efficient pre-regulator for linear regulators
On-card switching regulators
Positive to negative converter (Buck-Boost)
DESCRIPSION
ORDERING INFORMATION
Device
Package
LM2576HVDP-ADJ
SOP-8PP 8L
LM2576HVDP-X.X
LM2576HVR-ADJ
TO-263 5L
LM2576HVR-X.X
LM2576HVT-ADJ
TO-220 5L
LM2576HVT-X.X
X.X = Output Voltage = 3.3, 5.0, 12, 15
The LM2576HV series of regulators are monolithic integrated circuits that provide all the active functions for a
step-down (buck) switching regulator, capable of driving 3A load with excellent line and load regulation. These
devices are available in fixed output voltages of 3.3V, 5.0V, 12V, 15V and adjustable output versions.
Requiring a minimum number of external components, these regulators are simple to use and include internal
frequency compensation and a fixed-frequency oscillator. The LM2576HV series offers a high-efficiency
replacement for popular three-terminal linear regulators. It substantially reduces the size of the heat sink, and in
some cases no heat sink is required. A standard series of inductors optimized for use with the LM2576HV are
available from several different manufacturers. This feature greatly simplifies the design of switch-mode power
supplies. Other features include a guaranteed ± 4% tolerance on output voltage within specified input voltages
and output load conditions, and ± 10% on the oscillator frequency. External shutdown is included, featuring 50uA
(typical) standby current. The output switch includes cycle-by-cycle current limiting, as well as thermal shutdown
for full protection under fault conditions.
Absolute Maximum Ratings
(Note 1)
CHARACTERISTIC
Input Supply Voltage
ON/OFF Pin Input Voltage
Output Voltage to Ground (Steady State)
Lead Temperature (Soldering, 5 sec)
Storage Temperature Range
Maximum Junction Temperature Range
Feb. 2014 – R1.0
SYMBOL
V
IN
MIN.
-
-0.3
-0.75
MAX.
63
+ V
IN
260
UNIT
V
V
V
℃
℃
℃
T
SOL
T
STG
T
JOPR
-65
-
150
150
-1-
HTC
3A, 52kHz, Step-down Switching Regulator
ELECTRICAL CHARACTERISTICS
LM2576HV
Specifications with standard type face are for T
J
= 25℃ and those with boldface type apply over full operating temperature
range. Unless otherwise specified, V
IN
=12V for the 3.3V, 5V, and Adjustable version, V
IN
=25V for the 12V version, and
V
IN
=30V for the 15V version, I
LOAD
=500mA.
PARAMETER
SYMBOL
TEST CONDITION
(Note 2)
MIN.
TYP.
MAX.
UNIT
SYSTEM PARAMETERS
(Note 3)
V
IN
=12V, I
LOAD
=0.5A
Feedback Voltage
V
FB
LM2576HV-ADJ
0.5A
≤
I
LOAD
≤
3A ,
8V
≤
V
IN
≤
55V
V
IN
=12V, I
LOAD
=0.5A
LM2576HV-3.3
0.5A
≤
I
LOAD
≤
3A ,
6V
≤
VI
N
≤
55V
V
IN
=12V, I
LOAD
=0.5A
LM2576HV-5.0
Output Voltage
V
O
LM2576HV-12
0.5A
≤
I
LOAD
≤
3A ,
8V
≤
V
IN
≤
55V
V
IN
=25V, I
LOAD
=0.5A
0.5A
≤
I
LOAD
≤
3A ,
15V
≤
V
IN
≤
55V
V
IN
=25V, I
LOAD
=0.5A
LM2576HV-15
0.5A
≤
I
LOAD
≤
3A ,
18V
≤
V
IN
≤
55V
LM2576HV-ADJ
LM2576HV-3.3
Efficiency
LM2576HV-5.0
LM2576HV-12
LM2576HV-15
V
IN
=12V, I
LOAD
=3A,
Vo = 5V
V
IN
=12V, I
LOAD
=3A
V
IN
=12V, I
LOAD
=3A
V
IN
=15V, I
LOAD
=3A
V
IN
=18V, I
LOAD
=3A
1.217
1.193
1.180
3.234
3.168
3.135
4.900
4.800
4.750
11.76
11.52
11.40
14.70
14.40
14.25
1.230
1.230
3.300
3.300
5.000
5.000
12.00
12.00
15.00
15.00
77
75
77
88
88
1.243
1.273
1.286
3.366
3.450
3.482
5.100
5.225
5.275
12.24
12.54
12.66
15.30
15.68
15.83
V
V
V
V
V
V
V
V
V
V
%
%
%
%
%
DEVICE PARAMETERS
Feedback Bias
Current
Oscillator Frequency
Saturation Voltage
Max Duty Cycle(ON)
Current Limit
I
b
f
O
V
SAT
DC
I
CL
V
O
= 5V (Adjustable Version Only)
(Note 8)
I
O
= 3A (Note 4)
(Note 5)
(Note 4, 8)
93
4.2
3.5
47
42
50
52
1.4
98
5.8
6.9
7.5
100
500
58
63
1.55
1.70
nA
kHZ
V
%
A
Feb. 2014 – R1.0
-4-
HTC
3A, 52kHz, Step-down Switching Regulator
PARAMETER
Output Leakage
Current
Quiescent Current
Standby Quiescent
Current
SYMBOL
I
L
I
Q
I
STBY
TEST CONDITION
(Notes 6, 7) Output=0V
(Note 6)
ON/OFF Pin = 5V
(OFF)
V
IN
= 60V
MIN.
TYP.
7.5
5
50
LM2576HV
(Continued)
MAX.
UNIT
mA
10
200
mA
uA
ON
/OFF CONTROL
V
IH
V
IL
I
IH
I
IL
V
O
= 0V
V
O
= Nominal Output Voltage
ON
/OFF Pin = 5V (OFF)
ON
/OFF Pin = 0V (ON)
2.2
2.4
ON
/OFF Pin
1.4
1.2
12
0
1.0
0.8
30
10
V
V
uA
uA
Logic Input Level
ON
/OFF Pin
Input Current
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. All limits guaranteed at room temperature (standard type face) and at temperature extremes (bold type face).
Note 3. External components such as the catch diode, inductor, input and output capacitors can affect switching regulator system
performance. When the 2576HV is used as shown in the Figure 2 test circuit, system performance will be as shown in system
parameters section of Electrical Characteristics.
Note 4. Output pin sourcing current. No diode, inductor or capacitor connected to output.
Note 5. Feedback pin removed from output and connected to 0V.
Note 6. Feedback pin removed from output and connected to +12V for the Adjustable, 3.3V, and 5V, versions, and +25V for the 12V and 15V
versions, to force the output transistor OFF.
Note 7. V
IN
=60V.
Note 8. The oscillator frequency reduces to approximately 11 kHz in the event of an output short or an overload which causes the regulated
output voltage to drop approximately 40% from the nominal output voltage. This self protections feature lowers the average power
dissipation of the IC by lowering the minimum duty cycle from 5% down to approximately 2%.
Feb. 2014 – R1.0
-5-
HTC
FPGA/CPLD
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