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LM2588
SNVS117E – APRIL 1998 – REVISED JUNE 2019
LM2588 5-A Flyback Regulator With Shutdown
1 Features
3 Description
•
•
•
•
•
The LM2588 series of regulators are monolithic
integrated circuits specifically designed for flyback,
step-up (boost), and forward converter applications.
The device is available in 4 different output voltage
versions: 3.3 V, 5 V, 12 V, and adjustable.
1
•
•
•
•
•
•
•
•
Requires Few External Components
Family of Standard Inductors and Transformers
NPN Output Switches 5 A, Can Stand Off 65 V
Wide Input Voltage Range: 4 V to 40 V
Adjustable Switching Frequency: 100 kHz to 200
kHz
External Shutdown Capability
Draws Less Than 60 μA When Shut Down
Frequency Synchronization
Current-mode Operation for Improved Transient
Response, Line Regulation, and Current Limit
Internal Soft-start Function Reduces In-rush
Current During Start-up
Output Transistor Protected by Current Limit,
Undervoltage Lockout, and Thermal Shutdown
System Output Voltage Tolerance of ±4% Max
Over Line and Load Conditions
Create a Custom Design Using the LM2588With
the WEBENCH® Power Designer
2 Typical Applications
•
•
•
•
Flyback Regulator
Forward Converter
Multiple-output Regulator
Simple Boost Regulator
Requiring a minimum number of external
components, these regulators are cost effective, and
simple to use. Included in this data sheet are typical
circuits of boost and flyback regulators. Also listed
are selector guides for diodes and capacitors and a
family of standard inductors and flyback transformers
designed to work with these switching regulators.
The power switch is a 5-A NPN device that can
stand-off 65 V. Protecting the power switch are
current and thermal limiting circuits, and an
undervoltage lockout circuit. This IC contains an
adjustable frequency oscillator that can be
programmed up to 200 kHz. The oscillator can also
be synchronized with other devices, so that multiple
devices can operate at the same switching frequency.
Other features include soft start mode to reduce inrush current during start up, and current mode control
for improved rejection of input voltage and output
load transients and cycle-by-cycle current limiting.
The device also has a shutdown pin, so that it can be
turned off externally. An output voltage tolerance of
±4%, within specified input voltages and output load
conditions, is ensured for the power supply system.
Device Information(1)
PART NUMBER
LM2588
PACKAGE
BODY SIZE (NOM)
TO-220 (7)
10.1 mm × 8.89 mm
DDPAK /TO-263 (7) 14.986 mm × 10.16 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Flyback Regulator
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
LM2588
SNVS117E – APRIL 1998 – REVISED JUNE 2019
www.ti.com
Table of Contents
1
2
3
4
5
6
Features ..................................................................
Typical Applications ..............................................
Description .............................................................
Revision History.....................................................
Pin Configurations.................................................
Specifications.........................................................
1
1
1
2
3
4
6.1
6.2
6.3
6.4
6.5
6.6
6.7
6.8
Absolute Maximum Ratings ...................................... 4
ESD Ratings.............................................................. 4
Recommended Operating Ratings............................ 4
Electrical Characteristics: 3.3 V ................................ 5
Electrical Characteristics: 5 V ................................... 5
Electrical Characteristics: 12 V ................................. 6
Electrical Characteristics: Adjustable ........................ 6
Electrical Characteristics: All Output Voltage Versions
...................................................................................7
6.9 Typical Characteristics .............................................. 9
7
Detailed Description ............................................ 12
7.1 Overview ................................................................. 12
7.2 Functional Block Diagram ....................................... 12
7.3 Feature Description................................................. 12
8
Application and Implementation ........................ 18
8.1 Application Information............................................ 18
8.2 Typical Applications ............................................... 18
8.3 System Examples ................................................... 28
9
Layout ................................................................... 29
9.1 Layout Guidelines ................................................... 29
9.2 Layout Example ...................................................... 29
9.3 Heat Sink/Thermal Considerations ......................... 29
10 Device and Documentation Support ................. 31
10.1
10.2
10.3
10.4
10.5
10.6
Device Support......................................................
Receiving Notification of Documentation Updates
Community Resources..........................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
31
31
31
31
32
32
11 Mechanical, Packaging, and Orderable
Information ........................................................... 32
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision D (April 2013) to Revision E
Page
•
Editorial changes only; no technical revisions ....................................................................................................................... 1
•
Added links for WEBENCH ................................................................................................................................................... 1
Changes from Revision C (April 2013) to Revision D
•
2
Page
Changed layout of National Semiconductor data sheet to TI format .................................................................................... 1
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SNVS117E – APRIL 1998 – REVISED JUNE 2019
5 Pin Configurations
NDZ Package
7-Pin TO-220
Top View, Bent, Staggered Leads
KTW Package
7-Pin DDPAK/TO-263
Top View
NDZ Package
7-Pin TO-220
Side View; Bent, Staggered Leads
KTW Package
7-Pin DDPAK/TO-263
Side View
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SNVS117E – APRIL 1998 – REVISED JUNE 2019
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6 Specifications
6.1 Absolute Maximum Ratings
See
(1) (2)
−0.4V ≤ VIN ≤ 45V
Input Voltage
−0.4V ≤ VSW ≤ 65V
Switch Voltage
Switch Current (3)
Internally Limited
Compensation Pin Voltage
−0.4V ≤ VCOMP ≤ 2.4V
Feedback Pin Voltage
−0.4V ≤ VFB ≤ 2 VOUT
−0.4V ≤ VSH ≤ 6V
ON /OFF Pin Voltage
−0.4V ≤ VSYNC ≤ 2V
Sync Pin Voltage
Power Dissipation (4)
Internally Limited
−65°C to +150°C
Storage Temperature Range
Lead Temperature
(Soldering, 10 sec.)
260°C
Maximum Junction Temperature (4)
(1)
(2)
(3)
(4)
150°C
Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. These ratings apply when the current is
limited to less than 1.2 mA for pins 1, 2, 3, and 6. Operating ratings indicate conditions for which the device is intended to be functional,
but device parameter specifications may not be ensured under these conditions. For ensured specifications and test conditions, see the
Electrical Characteristics.
If Military/Aerospace specified devices are required, contact the TI Sales Office/ Distributors for availability and specifications.
Note that switch current and output current are not identical in a step-up regulator. Output current cannot be internally limited when the
LM2588 is used as a step-up regulator. To prevent damage to the switch, the output current must be externally limited to 5A. However,
output current is internally limited when the LM2588 is used as a flyback regulator (see the section for more information).
The junction temperature of the device (TJ) is a function of the ambient temperature (TA), the junction-to-ambient thermal resistance
(θJA), and the power dissipation of the device (PD). A thermal shutdown will occur if the temperature exceeds the maximum junction
temperature of the device: PD × θJA + TA(MAX) ≥ TJ(MAX). For a safe thermal design, check that the maximum power dissipated by the
device is less than: PD ≤ [TJ(MAX) − TA(MAX)]/θJA. When calculating the maximum allowable power dissipation, derate the maximum
junction temperature—this ensures a margin of safety in the thermal design.
6.2 ESD Ratings
V(ESD)
(1)
Electrostatic discharge
(minimum)
Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001
(C = 100 pF, R = 1.5 kΩ)
VALUE
UNIT
2000
V
(1)
JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
6.3 Recommended Operating Ratings
4V ≤ VIN ≤ 40V
Supply Voltage
0V ≤ VSW ≤ 60V
Output Switch Voltage
ISW ≤ 5.0A
Output Switch Current
−40°C ≤ TJ ≤ +125°C
Junction Temperature Range
4
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6.4 Electrical Characteristics: 3.3 V
Specifications with standard type face are for TJ = 25°C, and those in boldtype face apply over full Operating Temperature
Range. Unless otherwise specified, VIN = 5V.
PARAMETER
TEST CONDITIONS
TYP
MIN
MAX
UNIT
3.17/3.14
3.43/3.46
V
SYSTEM PARAMETERS Test Circuit of Figure 54 (1)
VOUT
Output Voltage
VIN = 4V to 12V
ILOAD = 400 mA to 1.75A
3.3
ΔVOUT/
ΔVIN
Line Regulation
VIN = 4V to 12V
ILOAD = 400 mA
20
50/100
mV
ΔVOUT/
ΔILOAD
Load Regulation
VIN = 12V
ILOAD = 400 mA to 1.75A
20
50/100
mV
η
Efficiency
VIN = 12V, ILOAD = 1A
75
Measured at Feedback Pin
VCOMP = 1.0V
3.3
UNIQUE DEVICE PARAMETERS
VREF
Output Reference
Voltage
ΔVREF
Reference Voltage Line VIN = 4V to 40V
Regulation
GM
Error Amp
Transconductance
ICOMP = −30 μA to +30 μA
VCOMP = 1.0V
AVOL
Error Amp Voltage
Gain
VCOMP = 0.5V to 1.6V
RCOMP = 1.0 MΩ (3)
(1)
(2)
(3)
%
(2)
3.242/3.234
3.358/3.366
V
2.0
mV
1.193
0.678
260
151/75
2.259
mmho
V/V
External components such as the diode, inductor, input and output capacitors can affect switching regulator performance. When the
LM2588 is used as shown in Figure 54 and Figure 55, system performance will be as specified by the system parameters.
All room temperature limits are 100% production tested, and all limits at temperature extremes are specified via correlation using
standard Statistical Quality Control (SQC) methods.
A 1.0 MΩ resistor is connected to the compensation pin (which is the error amplifier output) to ensure accuracy in measuring AVOL.
6.5 Electrical Characteristics: 5 V
Specifications with standard type face are for TJ = 25°C, and those in bold type face apply over full Operating Temperature
Range. Unless otherwise specified, VIN = 5V.
PARAMETER
TEST CONDITIONS
SYSTEM PARAMETERS Test Circuit of Figure 54
TYP
MIN
MAX
UNIT
4.80/4.75
5.20/5.25
V
(1)
VOUT
Output Voltage
VIN = 4V to 12V
ILOAD = 500 mA to 1.45A
5.0
ΔVOUT/
ΔVIN
Line Regulation
VIN = 4V to 12V
ILOAD = 500 mA
20
50/100
mV
ΔVOUT/
ΔILOAD
Load Regulation
VIN = 12V
ILOAD = 500 mA to 1.45A
20
50/100
mV
η
Efficiency
VIN = 12V, ILOAD = 750 mA
80
Measured at Feedback Pin
VCOMP = 1.0V
5.0
UNIQUE DEVICE PARAMETERS
VREF
Output Reference
Voltage
ΔVREF
Reference Voltage Line VIN = 4V to 40V
Regulation
GM
Error Amp
Transconductance
ICOMP = −30 μA to +30 μA
VCOMP = 1.0V
AVOL
Error Amp Voltage
Gain
VCOMP = 0.5V to 1.6V
RCOMP = 1.0 MΩ (3)
(1)
(2)
(3)
%
(2)
4.913/4.900
5.088/5.100
V
3.3
mV
0.750
0.447
165
99/49
1.491
mmho
V/V
External components such as the diode, inductor, input and output capacitors can affect switching regulator performance. When the
LM2588 is used as shown in Figure 54 and Figure 55, system performance will be as specified by the system parameters.
All room temperature limits are 100% production tested, and all limits at temperature extremes are specified via correlation using
standard Statistical Quality Control (SQC) methods.
A 1.0 MΩ resistor is connected to the compensation pin (which is the error amplifier output) to ensure accuracy in measuring AVOL.
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6.6 Electrical Characteristics: 12 V
Specifications with standard type face are for TJ = 25°C, and those in bold type face apply over full Operating Temperature
Range. Unless otherwise specified, VIN = 5V.
PARAMETER
TEST CONDITIONS
TYP
MIN
MAX
UNIT
12.0
11.52/11.40
12.48/12.60
V
20
100/200
mV
20
100/200
mV
SYSTEM PARAMETERS Test Circuit of Figure 55 (1)
VOUT
Output Voltage
VIN = 4V to 10V
ILOAD = 300 mA to 1.2A
ΔVOUT/
ΔVIN
Line Regulation
ΔVOUT/
ΔILOAD
Load Regulation
η
Efficiency
ILOAD = 300 mA
VIN = 10V
ILOAD = 300 mA to 1.2A
UNIQUE DEVICE PARAMETERS
VREF
VIN = 4V to 10V
VIN = 10V, ILOAD = 1A
Output Reference
Voltage
Measured at Feedback Pin
Reference Voltage Line VIN = 4V to 40V
Regulation
GM
Error Amp
Transconductance
ICOMP = −30 μA to +30 μA
Error Amp Voltage
Gain
VCOMP = 0.5V to 1.6V
(1)
(2)
(3)
%
12.0
11.79/11.76
12.21/12.24
V
VCOMP = 1.0V
ΔVREF
AVOL
90
(2)
7.8
mV
0.328
0.186
70
41/21
0.621
mmho
VCOMP = 1.0V
V/V
RCOMP = 1.0 MΩ (3)
External components such as the diode, inductor, input and output capacitors can affect switching regulator performance. When the
LM2588 is used as shown in Figure 54 and Figure 55, system performance will be as specified by the system parameters.
All room temperature limits are 100% production tested, and all limits at temperature extremes are specified via correlation using
standard Statistical Quality Control (SQC) methods.
A 1.0 MΩ resistor is connected to the compensation pin (which is the error amplifier output) to ensure accuracy in measuring AVOL.
6.7 Electrical Characteristics: Adjustable
Specifications with standard type face are for TJ = 25°C, and those in bold type face apply over full Operating Temperature
Range. Unless otherwise specified, VIN = 5V.
PARAMETER
TEST CONDITIONS
TYP
MIN
MAX
UNIT
12.0
11.52/11.40
12.48/12.60
V
SYSTEM PARAMETERS Test Circuit of Figure 55 (1)
VOUT
Output Voltage
VIN = 4V to 10V
ILOAD = 300 mA to 1.2A
ΔVOUT/
ΔVIN
Line Regulation
VIN = 4V to 10V
ILOAD = 300 mA
20
100/200
mV
ΔVOUT/
ΔILOAD
Load Regulation
VIN = 10V
ILOAD = 300 mA to 1.2A
20
100/200
mV
η
Efficiency
VIN = 10V, ILOAD = 1A
90
UNIQUE DEVICE PARAMETERS
VREF
Output Reference
Voltage
ΔVREF
Reference Voltage Line VIN = 4V to 40V
Regulation
GM
Error Amp
Transconductance
ICOMP = −30 μA to +30 μA
VCOMP = 1.0V
AVOL
Error Amp Voltage
Gain
IB
Error Amp Input Bias
Current
(1)
(2)
(3)
6
%
(2)
Measured at Feedback Pin
VCOMP = 1.0V
1.230
1.208/1.205
1.252/1.255
1.5
V
mV
3.200
1.800
VCOMP = 0.5V to 1.6V
RCOMP = 1.0 MΩ (3)
670
400/200
VCOMP = 1.0V
125
6.000
mmho
V/V
425/600
nA
External components such as the diode, inductor, input and output capacitors can affect switching regulator performance. When the
LM2588 is used as shown in Figure 54 and Figure 55, system performance will be as specified by the system parameters.
All room temperature limits are 100% production tested, and all limits at temperature extremes are specified via correlation using
standard Statistical Quality Control (SQC) methods.
A 1.0 MΩ resistor is connected to the compensation pin (which is the error amplifier output) to ensure accuracy in measuring AVOL.
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6.8 Electrical Characteristics: All Output Voltage Versions
(1)
Specifications with standard type face are for TJ = 25°C, and those in bold type face apply over full Operating Temperature
Range. Unless otherwise specified, VIN = 5V.
PARAMETER
MAX
UNIT
Switch Off (2)
TEST CONDITIONS
TYP
11
MIN
15.5/16.5
mA
ISWITCH = 3.0A
85
140/165
mA
VSH = 3V
16
100/300
μA
3.05
3.75
V
85/75
115/125
kHz
IS
Input Supply Current
IS/D
Shutdown Input
Supply Current
VUV
Input Supply
Undervoltage Lockout
RLOAD = 100Ω
3.30
fO
Oscillator Frequency
Measured at Switch Pin
RLOAD = 100Ω, VCOMP = 1.0V
Freq. Adj. Pin Open (Pin 1)
100
RSET = 22 kΩ
200
kHz
25
kHz
fSC
Short-Circuit Frequency Measured at Switch Pin
RLOAD = 100Ω
VFEEDBACK = 1.15V
VEAO
Error Amplifier Output
Swing
Upper Limit (3)
2.8
Lower Limit (2)
0.25
IEAO
Error Amp Output
Current (Source or
Sink)
See (4)
165
ISS
Soft Start Current
VFEEDBACK = 0.92V
VCOMP = 1.0V
DMAX
Maximum Duty Cycle
IL
2.6/2.4
V
0.40/0.55
V
110/70
260/320
μA
11.0
8.0/7.0
17.0/19.0
μA
RLOAD = 100Ω (3)
98
93/90
Switch Leakage
Current
Switch Off
VSWITCH = 60V
15
VSUS
Switch Sustaining
Voltage
dV/dT = 1.5V/ns
VSAT
Switch Saturation
Voltage
ISWITCH = 5.0A
ICL
NPN Switch Current
Limit
VSTH
Synchronization
Threshold Voltage
ISYNC
%
300/600
65
0.7
μA
V
1.1/1.4
V
6.5
5.0
9.5
A
FSYNC = 200 kHz
VCOMP = 1V, VIN = 5V
0.75
0.625/0.40
0.875/1.00
V
Synchronization
Pin Current
VIN = 5V
VCOMP = 1V, VSYNC = VSTH
100
200
μA
VSHTH
ON /OFF Pin (Pin 1)
Threshold Voltage
VCOMP = 1V (5)
ISH
ON /OFF Pin (Pin 1)
Current
VCOMP = 1V
VSH = VSHTH
(1)
(2)
(3)
(4)
(5)
1.6
1.0/0.8
2.2/2.4
V
40
15/10
65/75
μA
All room temperature limits are 100% production tested, and all limits at temperature extremes are specified via correlation using
standard Statistical Quality Control (SQC) methods.
To measure this parameter, the feedback voltage is set to a high value, depending on the output version of the device, to force the error
amplifier output low and the switch off.
To measure this parameter, the feedback voltage is set to a low value, depending on the output version of the device, to force the error
amplifier output high and the switch on.
To measure the worst-case error amplifier output current, the LM2588 is tested with the feedback voltage set to its low value (specified
in Note 3 under the Electrical Characteristics: All Output Voltage Versions (1) table) and at its high value (specified in Note 2 under the
Electrical Characteristics: All Output Voltage Versions (1) table).
When testing the minimum value, do not sink current from this pin—isolate it with a diode. If current is drawn from this pin, the frequency
adjust circuit will begin operation (see Figure 20).
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Electrical Characteristics: All Output Voltage Versions
(1)
(continued)
Specifications with standard type face are for TJ = 25°C, and those in bold type face apply over full Operating Temperature
Range. Unless otherwise specified, VIN = 5V.
PARAMETER
θJA
θJA
θJC
θJA
θJA
θJA
θJC
Thermal Resistance
TEST CONDITIONS
TYP
NDZ Package, Junction to Ambient (6)
NDZ Package, Junction to Ambient (7)
NDZ Package, Junction to Case
65
45
2
Junction to Ambient (8)
Junction to Ambient (9)
Junction to
56
35
26
2
KTW Package,
KTW Package,
KTW Package,
Ambient (10)
KTW Package,
MIN
MAX
UNIT
°C/W
Junction to Case
(6)
Junction to ambient thermal resistance (no external heat sink) for the 7 lead TO-220 package mounted vertically, with ½ inch leads in a
socket, or on a PC board with minimum copper area.
(7) Junction to ambient thermal resistance (no external heat sink) for the 7 lead TO-220 package mounted vertically, with ½ inch leads
soldered to a PC board containing approximately 4 square inches of (1 oz.) copper area surrounding the leads.
(8) Junction to ambient thermal resistance for the 7 lead TO-263 mounted horizontally against a PC board area of 0.136 square inches (the
same size as the TO-263 package) of 1 oz. (0.0014 in. thick) copper.
(9) Junction to ambient thermal resistance01242001 for the 7 lead TO-263 mounted horizontally against a PC board area of 0.4896 square
inches (3.6 times the area of the TO-263 package) of 1 oz. (0.0014 in. thick) copper.
(10) Junction to ambient thermal resistance for the 7 lead TO-263 mounted horizontally against a PC board copper area of 1.0064 square
inches (7.4 times the area of the TO-263 package) of 1 oz. (0.0014 in. thick) copper. Additional copper area will reduce thermal
resistance further. See the thermal model in Switchers Made Simple® software.
8
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6.9 Typical Characteristics
Figure 1. Supply Current vs Temperature
Figure 2. Reference Voltage vs Temperature
Figure 3. ΔReference Voltage vs Supply Voltage
Figure 4. Supply Current vs Switch Current
Figure 5. Current Limit vs Temperature
Figure 6. Feedback Pin Bias Current vs Temperature
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Typical Characteristics (continued)
10
Figure 7. Switch Saturation Voltage vs Temperature
Figure 8. Switch Transconductance vs Temperature
Figure 9. Oscillator Frequency vs Temperature
Figure 10. Error Amp Transconductance vs Temperature
Figure 11. Error Amp Voltage Gain vs Temperature
Figure 12. Short Circuit Frequency vs Temperature
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Typical Characteristics (continued)
Figure 13. Shutdown Supply Current vs Temperature
Figure 14. ON /Off Pin Current vs Voltage
Figure 15. Oscillator Frequency vs Resistance
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7 Detailed Description
7.1 Overview
The LM2588 series of regulators are monolithic integrated circuits specifically designed for flyback, step-up
(boost), and forward converter applications. The device is available in 4 different output voltage versions: 3.3 V,
5 V, 12 V, and adjustable. Requiring a minimum number of external components, these regulators are cost
effective, and simple to use. Included in the datasheet are typical circuits of boost and flyback regulators. Also
listed are selector guides for diodes and capacitors and a family of standard inductors and flyback transformers
designed to work with these switching regulators.
7.2 Functional Block Diagram
For Fixed Versions 3.3V, R1 = 3.4k, R2 = 2k5.0V, R1 = 6.15k, R2 = 2k12V, R1 = 8.73k, R2 = 1kFor Adj. VersionR1 =
Short (0Ω), R2 = Open
7.3 Feature Description
7.3.1 Flyback Regulator Operation
The operation of a flyback regulator is as follows (refer to Figure 16): when the switch is on, current flows
through the primary winding of the transformer, T1, storing energy in the magnetic field of the transformer. Note
that the primary and secondary windings are out of phase, so no current flows through the secondary when
current flows through the primary. When the switch turns off, the magnetic field collapses, reversing the voltage
polarity of the primary and secondary windings. Now rectifier D1 is forward biased and current flows through it,
releasing the energy stored in the transformer. This produces voltage at the output.
The output voltage is controlled by modulating the peak switch current. This is done by feeding back a portion of
the output voltage to the error amp, which amplifies the difference between the feedback voltage and a 1.23-V
reference. The error amp output voltage is compared to a ramp voltage proportional to the switch current (in
other words, inductor current during the switch on-time). The comparator terminates the switch on time when the
two voltages are equal, thereby controlling the peak switch current to maintain a constant output voltage.
12
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Feature Description (continued)
As shown in Figure 16, the LM2588 can be used as a flyback regulator by using a minimum number of external
components. The switching waveforms of this regulator are shown in Figure 18. Typical characteristics observed
during the operation of this circuit are shown in Figure 19.
Figure 16. 12-V Flyback Regulator Design Example
7.3.2 Step-Up (Boost) Regulator Operation
Figure 17 shows the LM2588 used as a step-up (boost) regulator. This is a switching regulator that produces an
output voltage greater than the input supply voltage.
A brief explanation of how the LM2588 boost regulator works is as follows (refer to Figure 17). When the NPN
switch turns on, the inductor current ramps up at the rate of VIN/L, storing energy in the inductor. When the
switch turns off, the lower end of the inductor flies above VIN, discharging its current through diode (D) into the
output capacitor (COUT) at a rate of (VOUT − VIN)/L. Thus, energy stored in the inductor during the switch on-time
is transferred to the output during the switch off time. The output voltage is controlled by adjusting the peak
switch current, as described in the section.
Figure 17. 12-V Boost Regulator
By adding a small number of external components (as shown in Figure 17), the LM2588 can be used to produce
a regulated output voltage that is greater than the applied input voltage. The switching waveforms observed
during the operation of this circuit are shown in . Typical performance of this regulator is shown in .
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Feature Description (continued)
A: Switch Voltage, 10V/div
B: Switch Current, 5A/div
C: Output Rectifier Current, 5A/div
D: Output Ripple Voltage, 100 mV/div
AC-Coupled
Figure 18. Switching Waveforms
Figure 19. VOUT Response To Load Current Step
7.3.3 Shutdown Control
A feature of the LM2588 is its ability to be shut down using the ON /OFF pin (pin 1). This feature conserves input
power by turning off the device when it is not in use. For proper operation, an isolation diode is required (as
shown in Figure 20).
The device will shut down when 3 V or greater is applied on the ON /OFF pin, sourcing current into pin 1. In shut
down mode, the device draws typically 56 μA of supply current (16 μA to VIN and 40 μA to the ON /OFF pin). To
turn the device back on, leave pin 1 floating, using an (isolation) diode, as shown in Figure 20 (for normal
operation, do not source or sink current to or from this pin—see the next section).
Figure 20. Shutdown Operation
7.3.4 Frequency Adjustment
The switching frequency of the LM2588 can be adjusted with the use of an external resistor. This feature allows
the user to optimize the size of the magnetics and the output capacitor(s) by tailoring the operating frequency. A
resistor connected from pin 1 (the Freq. Adj. pin) to ground will set the switching frequency from 100 kHz to 200
kHz (maximum). As shown in Figure 20, the pin can be used to adjust the frequency while still providing the shut
down function. A curve in the Performance Characteristics Section graphs the resistor value to the corresponding
switching frequency. The table in Table 1 shows resistor values corresponding to commonly used frequencies.
However, changing the LM2588's operating frequency from its nominal value of 100 kHz changes the magnetics
selection and compensation component values.
14
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Feature Description (continued)
Table 1. Frequency Setting Resistor Guide
RSET(kΩ)
FREQUENCY (kHz)
Open
100
200
125
47
150
33
175
22
200
7.3.5 Frequency Synchronization
Another feature of the LM2588 is the ability to synchronize the switching frequency to an external source, using
the sync pin (pin 6). This feature allows the user to parallel multiple devices to deliver more output power.
A negative falling pulse applied to the sync pin will synchronize the LM2588 to an external oscillator (see
Figure 21 and Figure 22).
Use of this feature enables the LM2588 to be synchronized to an external oscillator, such as a system clock. This
operation allows multiple power supplies to operate at the same frequency, thus eliminating frequency-related
noise problems.
Figure 21. Frequency Synchronization
The scope photo in Figure 22 shows a LM2588 12V Boost Regulator synchronized to a 200-kHz signal. There is
a 700 ns delay between the falling edge of the sync signal and the turning on of the switch.
Figure 22. Waveforms Of A Synchronized
12-V Boost Regulator
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7.3.6 Programming Output Voltage (Selecting R1 And R2)
Referring to the adjustable regulator in Figure 23, the output voltage is programmed by the resistors R1 and R2
by the following formula:
VOUT = VREF (1 + R1/R2)
where VREF = 1.23V
(1)
Resistors R1 and R2 divide the output voltage down so that it can be compared with the 1.23-V internal
reference. With R2 between 1k and 5k, R1 is:
R1 = R2 (VOUT/VREF − 1)
wher
where
•
e VREF = 1.23 V
(2)
For best temperature coefficient and stability with time, use 1% metal film resistors.
7.3.7 Short-Circuit Condition
Due to the inherent nature of boost regulators, when the output is shorted (see Figure 23 ), current flows directly
from the input, through the inductor and the diode, to the output, bypassing the switch. The current limit of the
switch does not limit the output current for the entire circuit. To protect the load and prevent damage to the
switch, the current must be externally limited, either by the input supply or at the output with an external current
limit circuit. The external limit should be set to the maximum switch current of the device, which is 5 A.
In a flyback regulator application (Figure 24 ), using the standard transformers, the LM2588 survives a short
circuit to the main output. When the output voltage drops to 80% of its nominal value, the frequency will drop to
25 kHz. With a lower frequency, off times are larger. With the longer off times, the transformer can release all of
its stored energy before the switch turns back on. Hence, the switch turns on initially with zero current at its
collector. In this condition, the switch current limit will limit the peak current, saving the device.
Figure 23. Boost Regulator
16
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Figure 24. Flyback Regulator
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8 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
8.1 Application Information
The LM2586 series of regulators are monolithic integrated circuits specifically designed for flyback, step-up
(boost), and forward converter applications. Requiring a minimum number of external components, these
regulators are cost effective, and simple to use. Included in the datasheet are typical circuits of boost and flyback
regulators. Also listed are selector guides for diodes and capacitors and a family of standard inductors and
flyback transformers designed to work with these switching regulators.
8.2 Typical Applications
8.2.1 Typical Flyback Regulator Applications
Figure 25 through Figure 30 show six typical flyback applications, varying from single output to triple output. Each
drawing contains the part number(s) and manufacturer(s) for every component except the transformer. For the
transformer part numbers and manufacturers' names, see Table 2. For applications with different output
voltages—requiring the LM2588-ADJ—or different output configurations that do not match the standard
configurations, refer to the Switchers Made Simple software.
Figure 25. Single-Output Flyback Regulator
18
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Typical Applications (continued)
Figure 26. Single-Output Flyback Regulator
Figure 27. Single-Output Flyback Regulator
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Typical Applications (continued)
Figure 28. Dual-Output Flyback Regulator
Figure 29. Dual-Output Flyback Regulator
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Typical Applications (continued)
Figure 30. Triple-Output Flyback Regulator
8.2.1.1 Design Requirements
8.2.1.1.1 Transformer Selection (T)
Table 2 lists the standard transformers available for flyback regulator applications. Included in the table are the
turns ratio(s) for each transformer, as well as the output voltages, input voltage ranges, and the maximum load
currents for each circuit.
Table 2. Transformer Selection Table
APPLICATIONS
Transformers
VIN
Figure 25
Figure 26
Figure 27
Figure 28
Figure 29
T1
T1
T1
T2
T3
Figure 30
T4
4V–6V
4V–6V
8V–16V
4V–6V
18V–36V
18V–36V
VOUT1
3.3V
5V
12V
12V
12V
5V
IOUT1 (Max)
1.8A
1.4A
1.2A
0.3A
1A
2.5A
1
1
1
2.5
0.8
0.35
VOUT2
−12V
−12V
12V
IOUT2 (Max)
0.3A
1A
0.5A
2.5
0.8
N1
N2
0.8
VOUT3
−12V
IOUT3 (Max)
0.5A
N3
0.8
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Table 3. Transformer Manufacturer Guide
Transformer
Type
(1)
(2)
(3)
(4)
Manufacturers' Part Numbers
Coilcraft (1)
Coilcraft Surface Mount (1) Pulse Surface Mount (2)
Renco (3)
Schott (4)
T1
Q4434-B
Q4435-B
PE-68411
RL-5530
67141450
T2
Q4337-B
Q4436-B
PE-68412
RL-5531
67140860
T3
Q4343-B
—
PE-68421
RL-5534
67140920
T4
Q4344-B
—
PE-68422
RL-5535
67140930
Coilcraft Inc.,: Phone: (800) 322-26451102 Silver Lake Road, Cary, IL 60013: Fax: (708) 639-1469European Headquarters, 21
Napier Place: Phone: +44 1236 730 595Wardpark North, Cumbernauld, Scotland G68 0LL: Fax: +44 1236 730 627
Pulse Engineering Inc.,: Phone: (619) 674-810012220 World Trade Drive, San Diego, CA 92128: Fax: (619) 674-8262European
Headquarters, Dunmore Road: Phone: +353 93 24 107Tuam, Co. Galway, Ireland: Fax: +353 93 24 459
Renco Electronics Inc.,: Phone: (800) 645-582860 Jeffryn Blvd. East, Deer Park, NY 11729: Fax: (516) 586-5562
Schott Corp.,: Phone: (612) 475-11731000 Parkers Lane Road, Wayzata, MN 55391: Fax: (612) 475-1786
8.2.1.1.2 Transformer Footprints
Figure 31 through Figure 48 show the footprints of each transformer, listed in Table 3.
Figure 31. T1 - Top View
Coilcraft Q4434-B
Figure 32. T2 - Top View
Coilcraft Q4337-B
Figure 33. T3 - Top View
Coilcraft Q4343-B
Figure 34. T4 - Top View
Coilcraft Q4344-B
Figure 35. T1 - Top View
Coilcraft Q4435-B
(Surface Mount)
22
Figure 36. T2 - Top View
Coilcraft Q4436-B
(Surface Mount)
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Figure 37. T1 - Top View
Pulse PE-68411
(Surface Mount)
Figure 38. T2 - Top View
Pulse PE-68412
(Surface Mount)
Figure 39. T3 - Top View
Pulse PE-68421
(Surface Mount)
Figure 40. T4 - Top View
Pulse PE-68422
(Surface Mount)
Figure 41. T1 - Top View
Renco RL-5530
Figure 42. T2 - Top View
Renco RL-5531
Figure 43. T3 - Top View
Renco RL-5534
Figure 44. T4 - Top View
Renco RL-5535
Figure 45. T1 - Top View
Schott 67141450
Figure 46. T2 - Top View
Schott 67140860
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Figure 48. T4 - Top View
Schott 67140930
Figure 47. T3 - Top View
Schott 67140920
8.2.1.2 Detailed Design Procedure
8.2.1.2.1 Custom Design With WEBENCH® Tools
Click here to create a custom design using the LM2588 device with the WEBENCH® Power Designer.
1. Start by entering the input voltage (VIN), output voltage (VOUT), and output current (IOUT) requirements.
2. Optimize the design for key parameters such as efficiency, footprint, and cost using the optimizer dial.
3. Compare the generated design with other possible solutions from Texas Instruments.
The WEBENCH Power Designer provides a customized schematic along with a list of materials with real-time
pricing and component availability.
In most cases, these actions are available:
• Run electrical simulations to see important waveforms and circuit performance
• Run thermal simulations to understand board thermal performance
• Export customized schematic and layout into popular CAD formats
• Print PDF reports for the design, and share the design with colleagues
Get more information about WEBENCH tools at www.ti.com/WEBENCH.
8.2.1.2.2 Flyback Regulator Input Capacitors
A flyback regulator draws discontinuous pulses of current from the input supply. Therefore, there are two input
capacitors needed in a flyback regulator—one for energy storage and one for filtering (see Figure 24). Both are
required due to the inherent operation of a flyback regulator. To keep a stable or constant voltage supply to the
LM2588, a storage capacitor (≥ 100 μF) is required. If the input source is a rectified DC supply and/or the
application has a wide temperature range, the required rms current rating of the capacitor might be very large.
This means a larger value of capacitance or a higher voltage rating will be needed for the input capacitor. The
storage capacitor will also attenuate noise which may interfere with other circuits connected to the same input
supply voltage.
In addition, a small bypass capacitor is required due to the noise generated by the input current pulses. To
eliminate the noise, insert a 1-μF ceramic capacitor between VIN and ground as close as possible to the device.
8.2.1.2.3 Switch Voltage Limits
In a flyback regulator, the maximum steady-state voltage appearing at the switch, when it is off, is set by the
transformer turns ratio, N, the output voltage, VOUT, and the maximum input voltage, VIN (maximum):
VSW(OFF) = VIN (max) + (VOUT + VF) / N
where
•
24
VF is the forward biased voltage of the output diode, and is typically 0.5 V for Schottky diodes and 0.8V for
ultra-fast recovery diodes
(3)
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In certain circuits, there exists a voltage spike, VLL, superimposed on top of the steady-state voltage (see
Figure 18, waveform A). Usually, this voltage spike is caused by the transformer leakage inductance and/or the
output rectifier recovery time. To “clamp” the voltage at the switch from exceeding its maximum value, a transient
suppressor in series with a diode is inserted across the transformer primary (as shown in the circuit in Figure 16
and other flyback regulator circuits throughout the datasheet). The schematic in Figure 24 shows another method
of clamping the switch voltage. A single voltage transient suppressor (the SA51A) is inserted at the switch pin.
This method clamps the total voltage across the switch, not just the voltage across the primary.
If poor circuit layout techniques are used (see the section), negative voltage transients may appear on the Switch
pin (pin 5). Applying a negative voltage (with respect to the IC's ground) to any monolithic IC pin causes erratic
and unpredictable operation of that IC. This holds true for the LM2588 IC as well. When used in a flyback
regulator, the voltage at the Switch pin (pin 5) can go negative when the switch turns on. The “ringing” voltage at
the switch pin is caused by the output diode capacitance and the transformer leakage inductance forming a
resonant circuit at the secondary(ies). The resonant circuit generates the “ringing” voltage, which gets reflected
back through the transformer to the switch pin. There are two common methods to avoid this problem. One is to
add an RC snubber around the output rectifier(s), as in Figure 24. The values of the resistor and the capacitor
must be chosen so that the voltage at the Switch pin does not drop below −0.4 V. The resistor may range in
value between 10Ω and 1 kΩ, and the capacitor will vary from 0.001 μF to 0.1 μF. Adding a snubber will (slightly)
reduce the efficiency of the overall circuit.
The other method to reduce or eliminate the “ringing” is to insert a Schottky diode clamp between pins 5 and 4
(ground), also shown in Figure 24. This prevents the voltage at pin 5 from dropping below −0.4 V. The reverse
voltage rating of the diode must be greater than the switch off voltage.
Figure 49. Input Line Filter
8.2.1.2.4 Output Voltage Limitations
The maximum output voltage of a boost regulator is the maximum switch voltage minus a diode drop. In a
flyback regulator, the maximum output voltage is determined by the turns ratio, N, and the duty cycle, D, by the
equation:
VOUT ≈ N × VIN × D / (1 − D)
(4)
The duty cycle of a flyback regulator is determined by the following equation:
(5)
Theoretically, the maximum output voltage can be as large as desired—just keep increasing the turns ratio of the
transformer. However, there exists some physical limitations that prevent the turns ratio, and thus the output
voltage, from increasing to infinity. The physical limitations are capacitances and inductances in the LM2588
switch, the output diode(s), and the transformer—such as reverse recovery time of the output diode (mentioned
above).
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8.2.1.2.5 Noisy Input Line Condition
A small, low-pass RC filter should be used at the input pin of the LM2588 if the input voltage has an unusually
large amount of transient noise, such as with an input switch that bounces. The circuit in Figure 49 demonstrates
the layout of the filter, with the capacitor placed from the input pin to ground and the resistor placed between the
input supply and the input pin. Note that the values of RIN and CIN shown in the schematic are good enough for
most applications, but some readjusting might be required for a particular application. If efficiency is a major
concern, replace the resistor with a small inductor (say 10 μH and rated at 200 mA).
8.2.1.2.6 Stability
All current-mode controlled regulators can suffer from an instability, known as subharmonic oscillation, if they
operate with a duty cycle above 50%. To eliminate subharmonic oscillations, a minimum value of inductance is
required to ensure stability for all boost and flyback regulators. The minimum inductance is given by:
where
•
VSAT is the switch saturation voltage and can be found in Typical Characteristics
(6)
8.2.2 Typical Boost Regulator Applications
Figure 50 and Figure 51 through Figure 53 show four typical boost applications—one fixed and three using the
adjustable version of the LM2588. Each drawing contains the part number(s) and manufacturer(s) for every
component. For the fixed 12-V output application, the part numbers and manufacturers' names for the inductor
are listed in a table in Table 4. For applications with different output voltages, refer to the Switchers Made
Simple™software.
Figure 50. 5-V to 12-V Boost Regulator
Figure 51. 12-V to 24-V Boost Regulator
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Figure 52. 24-V to 36-V Boost Regulator
*The LM2588 requires a heat sink in these applications. The size of the heat sink will depend on the maximum
ambient temperature. To calculate the thermal resistance of the IC and the size of the heat sink needed, see the Heat
Sink/Thermal Considerations section in Layout.
Figure 53. 24-V to 48-V Boost Regulator
8.2.2.1 Design Requirements
Table 4 contains a table of standard inductors, by part number and corresponding manufacturer, for the fixed
output regulator of Figure 50.
Table 4. Inductor Selection Table
Coilcraft
(1)
R4793-A
(1)
(2)
(3)
(4)
Pulse
(2)
PE-53900
Renco
(3)
RL-5472-5
Schott
(4)
67146520
Coilcraft Inc.,: Phone: (800) 322-26451102 Silver Lake Road, Cary, IL 60013: Fax: (708) 639-1469European Headquarters, 21
Napier Place: Phone: +44 1236 730 595Wardpark North, Cumbernauld, Scotland G68 0LL: Fax: +44 1236 730 627
Pulse Engineering Inc.,: Phone: (619) 674-810012220 World Trade Drive, San Diego, CA 92128: Fax: (619) 674-8262European
Headquarters, Dunmore Road: Phone: +353 93 24 107Tuam, Co. Galway, Ireland: Fax: +353 93 24 459
Renco Electronics Inc.,: Phone: (800) 645-582860 Jeffryn Blvd. East, Deer Park, NY 11729: Fax: (516) 586-5562
Schott Corp.,: Phone: (612) 475-11731000 Parkers Lane Road, Wayzata, MN 55391: Fax: (612) 475-1786
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8.2.2.2 Detailed Design Procedure
See Detailed Design Procedure
8.3 System Examples
8.3.1 Test Circuits
CIN1—100 μF, 25V Aluminum ElectrolyticCIN2—0.1 μF CeramicT—22 μH, 1:1 Schott
#67141450D—1N5820COUT—680 μF, 16V Aluminum ElectrolyticCC—0.47 μF CeramicRC—2k
Figure 54. 3.3-V and 5-V LM2588
CIN1—100 μF, 25V Aluminum ElectrolyticCIN2—0.1 μF CeramicL—15 μH, Renco #RL-5472-5D—1N5820COUT—680
μF, 16V Aluminum ElectrolyticCC—0.47 μF CeramicRC—2kFor 12V Devices: R1 = Short (0Ω) andR2 = OpenFor ADJ
Devices: R1 = 48.75k, ±0.1% andR2 = 5.62k, ±0.1%
Figure 55. 12-V and Adjustable LM2588
28
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9 Layout
9.1 Layout Guidelines
As in any switching regulator, layout is very important. Rapidly switching currents associated with wiring
inductance generate voltage transients which can cause problems. For minimal inductance and ground loops,
keep the length of the leads and traces as short as possible. Use single point grounding or ground plane
construction for best results. Separate the signal grounds from the power grounds (as indicated in Figure 56).
When using the Adjustable version, physically locate the programming resistors as near the regulator IC as
possible, to keep the sensitive feedback wiring short.
9.2 Layout Example
Figure 56. Circuit Board Layout
9.3 Heat Sink/Thermal Considerations
In many cases, a heat sink is not required to keep the LM2588 junction temperature within the allowed operating
temperature range. For each application, to determine whether or not a heat sink will be required, the following
must be identified:
1) Maximum ambient temperature (in the application).
2) Maximum regulator power dissipation (in the application).
3) Maximum allowed junction temperature (125°C for the LM2588). For a safe, conservative design, a
temperature approximately 15°C cooler than the maximum junction temperature should be selected (110°C).
4) LM2588 package thermal resistances θJA and θJC (given in the Electrical Characteristics).
Total power dissipated (PD) by the LM2588 can be estimated as follows:
Boost:
(7)
VIN is the minimum input voltage, VOUT is the output voltage, N is the transformer turns ratio, D is the duty cycle,
and ILOAD is the maximum load current (and ∑ILOAD is the sum of the maximum load currents for multiple-output
flyback regulators). The duty cycle is given by:
Boost:
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Heat Sink/Thermal Considerations (continued)
where
•
•
VF is the forward biased voltage of the diode and is typically 0.5V for Schottky diodes and 0.8V for fast
recovery diodes
VSAT is the switch saturation voltage and can be found in the Characteristic Curves.
(8)
When no heat sink is used, the junction temperature rise is:
ΔTJ = PD • θJA.
(9)
Adding the junction temperature rise to the maximum ambient temperature gives the actual operating junction
temperature:
TJ = ΔTJ + TA.
(10)
If the operating junction temperature exceeds the maximum junction temperatue in item 3 above, then a heat
sink is required. When using a heat sink, the junction temperature rise can be determined by the following:
ΔTJ = PD • (θJC + θInterface + θHeat Sink)
(11)
Again, the operating junction temperature will be:
TJ = ΔTJ + TA
(12)
As before, if the maximum junction temperature is exceeded, a larger heat sink is required (one that has a lower
thermal resistance).
Included in the Switchers Made Simple™ design software is a more precise (non-linear) thermal model that can
be used to determine junction temperature with different input-output parameters or different component values.
It can also calculate the heat sink thermal resistance required to maintain the regulator junction temperature
below the maximum operating temperature.
30
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10 Device and Documentation Support
10.1 Device Support
10.1.1 Third-Party Products Disclaimer
TI'S PUBLICATION OF INFORMATION REGARDING THIRD-PARTY PRODUCTS OR SERVICES DOES NOT
CONSTITUTE AN ENDORSEMENT REGARDING THE SUITABILITY OF SUCH PRODUCTS OR SERVICES
OR A WARRANTY, REPRESENTATION OR ENDORSEMENT OF SUCH PRODUCTS OR SERVICES, EITHER
ALONE OR IN COMBINATION WITH ANY TI PRODUCT OR SERVICE.
10.1.2 Development Support
10.1.2.1 Custom Design With WEBENCH® Tools
Click here to create a custom design using the LM2586 device with the WEBENCH® Power Designer.
1. Start by entering the input voltage (VIN), output voltage (VOUT), and output current (IOUT) requirements.
2. Optimize the design for key parameters such as efficiency, footprint, and cost using the optimizer dial.
3. Compare the generated design with other possible solutions from Texas Instruments.
The WEBENCH Power Designer provides a customized schematic along with a list of materials with real-time
pricing and component availability.
In most cases, these actions are available:
• Run electrical simulations to see important waveforms and circuit performance
• Run thermal simulations to understand board thermal performance
• Export customized schematic and layout into popular CAD formats
• Print PDF reports for the design, and share the design with colleagues
Get more information about WEBENCH tools at www.ti.com/WEBENCH.
10.2 Receiving Notification of Documentation Updates
To receive notification of documentation updates, navigate to the device product folder on ti.com. In the upper
right corner, click on Alert me to register and receive a weekly digest of any product information that has
changed. For change details, review the revision history included in any revised document.
10.3 Community Resources
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of
Use.
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help
solve problems with fellow engineers.
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and
contact information for technical support.
10.4 Trademarks
Switchers Made Simple, E2E are trademarks of Texas Instruments.
WEBENCH is a registered trademark of Texas Instruments.
Switchers Made Simple is a registered trademark of dcl_owner.
All other trademarks are the property of their respective owners.
Submit Documentation Feedback
Copyright © 1998–2019, Texas Instruments Incorporated
Product Folder Links: LM2588
31
LM2588
SNVS117E – APRIL 1998 – REVISED JUNE 2019
www.ti.com
10.5 Electrostatic Discharge Caution
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more
susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.
10.6 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
11 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
32
Submit Documentation Feedback
Copyright © 1998–2019, Texas Instruments Incorporated
Product Folder Links: LM2588
PACKAGE OPTION ADDENDUM
www.ti.com
30-Sep-2021
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
(6)
LM2588S-12/NOPB
ACTIVE
DDPAK/
TO-263
KTW
7
45
RoHS-Exempt
& Green
SN
Level-3-245C-168 HR
-40 to 125
LM2588S
-12 P+
LM2588S-3.3/NOPB
ACTIVE
DDPAK/
TO-263
KTW
7
45
RoHS-Exempt
& Green
SN
Level-3-245C-168 HR
-40 to 125
LM2588S
-3.3 P+
LM2588S-5.0/NOPB
ACTIVE
DDPAK/
TO-263
KTW
7
45
RoHS-Exempt
& Green
SN
Level-3-245C-168 HR
-40 to 125
LM2588S
-5.0 P+
LM2588S-ADJ
NRND
DDPAK/
TO-263
KTW
7
45
Non-RoHS
& Green
Call TI
Level-3-235C-168 HR
-40 to 125
LM2588S
-ADJ P+
LM2588S-ADJ/NOPB
ACTIVE
DDPAK/
TO-263
KTW
7
45
RoHS-Exempt
& Green
SN
Level-3-245C-168 HR
-40 to 125
LM2588S
-ADJ P+
LM2588SX-12/NOPB
ACTIVE
DDPAK/
TO-263
KTW
7
500
RoHS-Exempt
& Green
SN
Level-3-245C-168 HR
-40 to 125
LM2588S
-12 P+
LM2588SX-3.3/NOPB
ACTIVE
DDPAK/
TO-263
KTW
7
500
RoHS-Exempt
& Green
SN
Level-3-245C-168 HR
-40 to 125
LM2588S
-3.3 P+
LM2588SX-5.0/NOPB
ACTIVE
DDPAK/
TO-263
KTW
7
500
RoHS-Exempt
& Green
SN
Level-3-245C-168 HR
-40 to 125
LM2588S
-5.0 P+
LM2588SX-ADJ/NOPB
ACTIVE
DDPAK/
TO-263
KTW
7
500
RoHS-Exempt
& Green
SN
Level-3-245C-168 HR
-40 to 125
LM2588S
-ADJ P+
LM2588T-3.3/NOPB
ACTIVE
TO-220
NDZ
7
45
RoHS-Exempt
& Green
SN
Level-1-NA-UNLIM
-40 to 125
LM2588T
-3.3 P+
LM2588T-5.0/NOPB
ACTIVE
TO-220
NDZ
7
45
RoHS-Exempt
& Green
SN
Level-1-NA-UNLIM
-40 to 125
LM2588T
-5.0 P+
LM2588T-ADJ/NOPB
ACTIVE
TO-220
NDZ
7
45
RoHS-Exempt
& Green
SN
Level-1-NA-UNLIM
-40 to 125
LM2588T
-ADJ P+
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
30-Sep-2021
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of
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