LM2588 [TI]

SIMPLE SWITCHER 5A Flyback Regulator with Shutdown;
LM2588
型号: LM2588
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

SIMPLE SWITCHER 5A Flyback Regulator with Shutdown

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LM2588  
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SNVS117D APRIL 1998REVISED APRIL 2013  
®
LM2588 SIMPLE SWITCHER 5A Flyback Regulator with Shutdown  
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1
FEATURES  
DESCRIPTION  
The LM2588 series of regulators are monolithic  
2345  
Requires Few External Components  
integrated circuits specifically designed for flyback,  
step-up (boost), and forward converter applications.  
The device is available in 4 different output voltage  
versions: 3.3V, 5.0V, 12V, and adjustable.  
Family of Standard Inductors and  
Transformers  
NPN Output Switches 5.0A, Can Stand Off 65V  
Wide Input Voltage Range: 4V to 40V  
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.  
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  
The power switch is a 5.0A NPN device that can  
stand-off 65V. 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.  
Internal Soft-start Function Reduces In-rush  
Current During Start-up  
Output Transistor Protected by Current Limit,  
Under Voltage Lockout, and Thermal  
Shutdown  
Other features include soft start mode to reduce in-  
rush 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.  
System Output Voltage Tolerance of ±4% Max  
Over Line and Load Conditions  
TYPICAL APPLICATIONS  
Flyback Regulator  
Forward Converter  
Multiple-output Regulator  
Simple Boost Regulator  
Connection Diagrams  
7-Pin  
Top View  
Bent, 7-Pin  
Side View  
Figure 1. LM2588T-12 or LM2588T-ADJ  
See Package Number NDZ0007B  
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Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of  
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.  
Switchers Made Simple is a trademark of Texas Instruments.  
SIMPLE SWITCHER is a registered trademark of Texas Instruments.  
Switchers Made Simple is a registered trademark of dcl_owner.  
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All other trademarks are the property of their respective owners.  
PRODUCTION DATA information is current as of publication date.  
Products conform to specifications per the terms of the Texas  
Instruments standard warranty. Production processing does not  
necessarily include testing of all parameters.  
Copyright © 1998–2013, Texas Instruments Incorporated  
LM2588  
SNVS117D APRIL 1998REVISED APRIL 2013  
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7-Pin  
Top View  
7-Pin  
Side View  
Figure 2. LM2588S-12 or LM2588S-ADJ  
See Package Number KTW0007B  
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam  
during storage or handling to prevent electrostatic damage to the MOS gates.  
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Absolute Maximum Ratings(1)(2)  
Input Voltage  
0.4V VIN 45V  
0.4V VSW 65V  
Internally Limited  
0.4V VCOMP 2.4V  
0.4V VFB 2 VOUT  
0.4V VSH 6V  
0.4V VSYNC 2V  
Internally Limited  
65°C to +150°C  
260°C  
Switch Voltage  
Switch Current(3)  
Compensation Pin Voltage  
Feedback Pin Voltage  
ON /OFF Pin Voltage  
Sync Pin Voltage  
Power Dissipation(4)  
Storage Temperature Range  
Lead Temperature  
(Soldering, 10 sec.)  
Maximum Junction Temperature(4)  
150°C  
Minimum ESD Rating  
(C = 100 pF, R = 1.5 kΩ)  
2 kV  
(1) 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.  
(2) If Military/Aerospace specified devices are required, please contact the TI Sales Office/ Distributors for availability and specifications.  
(3) 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 Application Hints section for more  
information).  
(4) 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.  
Operating Ratings  
Supply Voltage  
4V VIN 40V  
0V VSW 60V  
Output Switch Voltage  
Output Switch Current  
Junction Temperature Range  
ISW 5.0A  
40°C TJ +125°C  
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LM2588-3.3 Electrical Characteristics  
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.  
Symbol  
Parameters  
Conditions  
Typical  
Min  
Max  
Units  
SYSTEM PARAMETERS Test Circuit of Figure 18(1)  
VOUT  
Output Voltage  
Line Regulation  
Load Regulation  
Efficiency  
VIN = 4V to 12V  
ILOAD = 400 mA to 1.75A  
3.3  
20  
3.17/3.14  
3.43/3.46  
50/100  
V
ΔVOUT  
ΔVIN  
/
/
VIN = 4V to 12V  
ILOAD = 400 mA  
mV  
ΔVOUT  
ΔILOAD  
VIN = 12V  
ILOAD = 400 mA to 1.75A  
20  
75  
50/100  
mV  
%
η
VIN = 12V, ILOAD = 1A  
UNIQUE DEVICE PARAMETERS(2)  
VREF  
ΔVREF  
GM  
Output Reference  
Voltage  
Measured at Feedback Pin  
VCOMP = 1.0V  
3.3  
2.0  
3.242/3.234  
3.358/3.366  
V
Reference Voltage Line VIN = 4V to 40V  
Regulation  
mV  
Error Amp  
Transconductance  
ICOMP = 30 μA to +30 μA  
VCOMP = 1.0V  
1.193  
260  
0.678  
2.259  
mmho  
V/V  
AVOL  
Error Amp Voltage  
Gain  
VCOMP = 0.5V to 1.6V  
151/75  
RCOMP = 1.0 MΩ(3)  
(1) 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 18 and Figure 19, system performance will be as specified by the system parameters.  
(2) 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.  
(3) 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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LM2588-5.0 Electrical Characteristics  
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.  
Symbol  
Parameters  
Conditions  
Typical  
Min  
Max  
Units  
SYSTEM PARAMETERS Test Circuit of Figure 18(1)  
VOUT  
Output Voltage  
Line Regulation  
Load Regulation  
Efficiency  
VIN = 4V to 12V  
ILOAD = 500 mA to 1.45A  
5.0  
20  
4.80/4.75  
5.20/5.25  
50/100  
V
ΔVOUT  
ΔVIN  
/
/
VIN = 4V to 12V  
ILOAD = 500 mA  
mV  
ΔVOUT  
ΔILOAD  
VIN = 12V  
ILOAD = 500 mA to 1.45A  
20  
80  
50/100  
mV  
%
η
VIN = 12V, ILOAD = 750 mA  
UNIQUE DEVICE PARAMETERS(2)  
VREF  
ΔVREF  
GM  
Output Reference  
Voltage  
Measured at Feedback Pin  
VCOMP = 1.0V  
5.0  
3.3  
4.913/4.900  
5.088/5.100  
V
Reference Voltage Line VIN = 4V to 40V  
Regulation  
mV  
Error Amp  
Transconductance  
ICOMP = 30 μA to +30 μA  
VCOMP = 1.0V  
0.750  
165  
0.447  
1.491  
mmho  
V/V  
AVOL  
Error Amp Voltage  
Gain  
VCOMP = 0.5V to 1.6V  
99/49  
RCOMP = 1.0 MΩ(3)  
(1) 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 18 and Figure 19, system performance will be as specified by the system parameters.  
(2) 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.  
(3) 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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LM2588-12 Electrical Characteristics  
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.  
Symbol  
Parameters  
Conditions  
Typical  
12.0  
20  
Min  
Max  
Units  
SYSTEM PARAMETERS Test Circuit of Figure 19(1)  
VOUT  
Output Voltage  
Line Regulation  
Load Regulation  
Efficiency  
VIN = 4V to 10V  
11.52/11.40  
12.48/12.60  
100/200  
V
ILOAD = 300 mA to 1.2A  
VIN = 4V to 10V  
ΔVOUT  
ΔVIN  
/
/
mV  
mV  
%
ILOAD = 300 mA  
ΔVOUT  
VIN = 10V  
20  
100/200  
ΔILOAD  
ILOAD = 300 mA to 1.2A  
VIN = 10V, ILOAD = 1A  
η
90  
UNIQUE DEVICE PARAMETERS(2)  
VREF  
Output Reference  
Voltage  
Measured at Feedback Pin  
VCOMP = 1.0V  
12.0  
11.79/11.76  
12.21/12.24  
V
ΔVREF  
Reference Voltage Line VIN = 4V to 40V  
Regulation  
7.8  
mV  
GM  
Error Amp  
ICOMP = 30 μA to +30 μA  
0.328  
0.186  
0.621  
mmho  
Transconductance  
VCOMP = 1.0V  
AVOL  
Error Amp Voltage  
Gain  
VCOMP = 0.5V to 1.6V  
RCOMP = 1.0 MΩ(3)  
70  
41/21  
V/V  
(1) 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 18 and Figure 19, system performance will be as specified by the system parameters.  
(2) 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.  
(3) 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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LM2588-ADJ Electrical Characteristics  
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.  
Symbol  
Parameters  
Conditions  
Typical  
Min  
Max  
Units  
SYSTEM PARAMETERS Test Circuit of Figure 19(1)  
VOUT  
Output Voltage  
Line Regulation  
Load Regulation  
Efficiency  
VIN = 4V to 10V  
ILOAD = 300 mA to 1.2A  
12.0  
20  
11.52/11.40  
12.48/12.60  
100/200  
V
ΔVOUT  
ΔVIN  
/
/
VIN = 4V to 10V  
ILOAD = 300 mA  
mV  
ΔVOUT  
ΔILOAD  
VIN = 10V  
ILOAD = 300 mA to 1.2A  
20  
90  
100/200  
mV  
%
η
VIN = 10V, ILOAD = 1A  
UNIQUE DEVICE PARAMETERS(2)  
VREF  
ΔVREF  
GM  
Output Reference  
Voltage  
Measured at Feedback Pin  
VCOMP = 1.0V  
1.230  
1.5  
1.208/1.205  
1.252/1.255  
6.000  
V
mV  
Reference Voltage Line VIN = 4V to 40V  
Regulation  
Error Amp  
Transconductance  
ICOMP = 30 μA to +30 μA  
VCOMP = 1.0V  
3.200  
670  
1.800  
mmho  
V/V  
nA  
AVOL  
IB  
Error Amp Voltage  
Gain  
VCOMP = 0.5V to 1.6V  
400/200  
RCOMP = 1.0 MΩ(3)  
Error Amp Input Bias  
Current  
VCOMP = 1.0V  
125  
425/600  
(1) 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 18 and Figure 19, system performance will be as specified by the system parameters.  
(2) 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.  
(3) A 1.0 MΩ resistor is connected to the compensation pin (which is the error amplifier output) to ensure accuracy in measuring AVOL  
.
All Output Voltage Versions Electrical Characteristics(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.  
Symbol  
Parameters  
Conditions  
Typical  
11  
Min  
Max  
Units  
mA  
IS  
Input Supply Current  
Switch Off(2)  
15.5/16.5  
140/165  
ISWITCH = 3.0A  
VSH = 3V  
85  
mA  
IS/D  
VUV  
fO  
Shutdown Input  
Supply Current  
16  
100/300  
μA  
Input Supply  
Undervoltage Lockout  
RLOAD = 100Ω  
3.30  
3.05  
3.75  
V
Oscillator Frequency  
Measured at Switch Pin  
RLOAD = 100Ω, VCOMP = 1.0V  
Freq. Adj. Pin Open (Pin 1)  
100  
85/75  
115/125  
kHz  
RSET = 22 kΩ  
200  
25  
kHz  
kHz  
fSC  
Short-Circuit Frequency Measured at Switch Pin  
RLOAD = 100Ω  
VFEEDBACK = 1.15V  
VEAO  
Error Amplifier Output  
Swing  
Upper Limit(3)  
Lower Limit(2)  
2.8  
2.6/2.4  
V
V
0.25  
0.40/0.55  
(1) 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.  
(2) 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.  
(3) 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.  
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All Output Voltage Versions Electrical Characteristics(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.  
Symbol  
IEAO  
Parameters  
Conditions  
Typical  
Min  
Max  
Units  
Error Amp Output  
Current (Source or  
Sink)  
See(4)  
165  
110/70  
260/320  
μA  
ISS  
Soft Start Current  
VFEEDBACK = 0.92V  
VCOMP = 1.0V  
RLOAD = 100Ω(3)  
11.0  
98  
8.0/7.0  
93/90  
17.0/19.0  
300/600  
μA  
%
DMAX  
IL  
Maximum Duty Cycle  
Switch Leakage  
Current  
Switch Off  
VSWITCH = 60V  
15  
μA  
V
VSUS  
VSAT  
ICL  
Switch Sustaining  
Voltage  
dV/dT = 1.5V/ns  
65  
Switch Saturation  
Voltage  
ISWITCH = 5.0A  
0.7  
6.5  
1.1/1.4  
V
A
NPN Switch Current  
Limit  
5.0  
9.5  
VSTH  
ISYNC  
VSHTH  
ISH  
Synchronization  
Threshold Voltage  
FSYNC = 200 kHz  
VCOMP = 1V, VIN = 5V  
0.75  
100  
1.6  
40  
0.625/0.40  
0.875/1.00  
200  
V
μA  
V
Synchronization  
Pin Current  
VIN = 5V  
VCOMP = 1V, VSYNC = VSTH  
VCOMP = 1V(5)  
ON /OFF Pin (Pin 1)  
Threshold Voltage  
1.0/0.8  
15/10  
2.2/2.4  
65/75  
ON /OFF Pin (Pin 1)  
Current  
VCOMP = 1V  
VSH = VSHTH  
μA  
θJA  
θJA  
θJC  
Thermal Resistance  
NDZ Package, Junction to Ambient(6)  
NDZ Package, Junction to Ambient(7)  
NDZ Package, Junction to Case  
65  
45  
2
θJA  
θJA  
θJA  
θJC  
KTW Package, Junction to Ambient(8)  
KTW Package, Junction to Ambient(9)  
KTW Package, Junction to  
Ambient(10)  
56  
35  
26  
2
°C/W  
KTW Package, Junction to Case  
(4) 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 All Output Voltage Versions Electrical Characteristics() table) and at its high value (specified in Note 2 under the All  
Output Voltage Versions Electrical Characteristics() table).  
(5) 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 54).  
(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.  
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Typical Performance Characteristics  
Supply Current  
vs Temperature  
Reference Voltage  
vs Temperature  
Figure 3.  
Figure 4.  
ΔReference Voltage  
vs Supply Voltage  
Supply Current  
vs Switch Current  
Figure 5.  
Figure 6.  
Feedback Pin Bias  
Current  
Current Limit  
vs Temperature  
vs  
Temperature  
Figure 7.  
Figure 8.  
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Typical Performance Characteristics (continued)  
Switch Saturation  
Voltage  
vs  
Switch Transconductance  
vs Temperature  
Temperature  
Figure 9.  
Figure 10.  
Oscillator Frequency  
vs Temperature  
Error Amp Transconductance  
vs Temperature  
Figure 11.  
Figure 12.  
Error Amp Voltage  
Gain  
vs  
Temperature  
Short Circuit Frequency  
vs Temperature  
Figure 13.  
Figure 14.  
10  
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Typical Performance Characteristics (continued)  
Shutdown Supply Current  
vs Temperature  
ON /OFF Pin Current  
vs Voltage  
Figure 15.  
Figure 16.  
Oscillator Frequency  
vs Resistance  
Figure 17.  
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Flyback Regulator  
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 18. LM2588-3.3 and LM2588-5.0  
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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 19. LM2588-12 and LM2588-ADJ  
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  
Flyback Regulator Operation  
The LM2588 is ideally suited for use in the flyback regulator topology. The flyback regulator can produce a single  
output voltage, such as the one shown in Figure 20, or multiple output voltages. In Figure 20, the flyback  
regulator generates an output voltage that is inside the range of the input voltage. This feature is unique to  
flyback regulators and cannot be duplicated with buck or boost regulators.  
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The operation of a flyback regulator is as follows (refer to Figure 20): 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 1.230V  
reference. The error amp output voltage is compared to a ramp voltage proportional to the switch current (i.e.,  
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.  
As shown in Figure 20, 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 21. Typical Performance Characteristics  
observed during the operation of this circuit are shown in Figure 22.  
Figure 20. 12V Flyback Regulator Design Example  
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Typical Performance Characteristics  
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 21. Switching Waveforms  
Figure 22. VOUT Response to Load Current Step  
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Typical Flyback Regulator Applications  
Figure 23 through Figure 28 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 1. 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 23. Single-Output Flyback Regulator  
Figure 24. Single-Output Flyback Regulator  
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Figure 25. Single-Output Flyback Regulator  
Figure 26. Dual-Output Flyback Regulator  
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Figure 27. Dual-Output Flyback Regulator  
Figure 28. Triple-Output Flyback Regulator  
TRANSFORMER SELECTION (T)  
Table 1 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.  
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Table 1. Transformer Selection Table  
Applications  
Transformers  
VIN  
Figure 23  
T1  
Figure 24  
T1  
Figure 25  
T1  
Figure 26  
T2  
Figure 27  
T3  
Figure 28  
T4  
4V–6V  
3.3V  
1.8A  
1
4V–6V  
5V  
8V–16V  
12V  
4V–6V  
12V  
18V–36V  
12V  
18V–36V  
5V  
VOUT1  
IOUT1 (Max)  
N1  
1.4A  
1
1.2A  
0.3A  
2.5  
1A  
2.5A  
0.35  
1
0.8  
VOUT2  
12V  
0.3A  
2.5  
12V  
1A  
12V  
IOUT2 (Max)  
N2  
0.5A  
0.8  
0.8  
VOUT3  
12V  
0.5A  
0.8  
IOUT3 (Max)  
N3  
Table 2. Transformer Manufacturer Guide  
Transformer  
Type  
Manufacturers' Part Numbers  
Coilcraft Surface Mount(1) Pulse Surface Mount(2)  
Coilcraft(1)  
Q4434-B  
Q4337-B  
Q4343-B  
Q4344-B  
Renco(3)  
RL-5530  
RL-5531  
RL-5534  
RL-5535  
Schott(4)  
67141450  
67140860  
67140920  
67140930  
T1  
T2  
T3  
T4  
Q4435-B  
Q4436-B  
PE-68411  
PE-68412  
PE-68421  
PE-68422  
(1) 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  
(2) 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  
(3) Renco Electronics Inc.,: Phone: (800) 645-582860 Jeffryn Blvd. East, Deer Park, NY 11729: Fax: (516) 586-5562  
(4) Schott Corp.,: Phone: (612) 475-11731000 Parkers Lane Road, Wayzata, MN 55391: Fax: (612) 475-1786  
TRANSFORMER FOOTPRINTS  
Figure 29 through Figure 46 show the footprints of each transformer, listed in Table 2.  
Figure 29. T1 - Top View  
Coilcraft Q4434-B  
Figure 30. T2 - Top View  
Coilcraft Q4337-B  
Figure 31. T3 - Top View  
Coilcraft Q4343-B  
Figure 32. T4 - Top View  
Coilcraft Q4344-B  
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Figure 33. T1 - Top View  
Coilcraft Q4435-B  
(Surface Mount)  
Figure 34. T2 - Top View  
Coilcraft Q4436-B  
(Surface Mount)  
Figure 35. T1 - Top View  
Pulse PE-68411  
Figure 36. T2 - Top View  
Pulse PE-68412  
(Surface Mount)  
(Surface Mount)  
Figure 37. T3 - Top View  
Pulse PE-68421  
Figure 38. T4 - Top View  
Pulse PE-68422  
(Surface Mount)  
(Surface Mount)  
Figure 39. T1 - Top View  
Renco RL-5530  
Figure 40. T2 - Top View  
Renco RL-5531  
Figure 41. T3 - Top View  
Renco RL-5534  
Figure 42. T4 - Top View  
Renco RL-5535  
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Figure 43. T1 - Top View  
Schott 67141450  
Figure 44. T2 - Top View  
Schott 67140860  
Figure 45. T3 - Top View  
Schott 67140920  
Figure 46. T4 - Top View  
Schott 67140930  
Step-Up (Boost) Regulator Operation  
Figure 47 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 47). 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 Flyback Regulator section.  
Figure 47. 12V Boost Regulator  
By adding a small number of external components (as shown in Figure 47), 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 Figure 48. Typical performance of this regulator is shown in  
Figure 49.  
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Typical Performance Characteristics  
A: Switch Voltage,10V/div  
B: Switch Current, 5A/div  
C: Inductor Current, 5A/div  
D: Output Ripple Voltage,  
100 mV/div, AC-Coupled  
Figure 48. Switching Waveforms  
Figure 49. VOUT Response to Load Current Step  
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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 12V output application, the part numbers and manufacturers' names for the inductor  
are listed in a table in Table 3. For applications with different output voltages, refer to the Switchers Made  
Simplesoftware.  
Figure 50. +5V to +12V Boost Regulator  
Table 3 contains a table of standard inductors, by part number and corresponding manufacturer, for the fixed  
output regulator of Figure 50.  
Table 3. Inductor Selection Table  
(1)  
(2)  
(3)  
(4)  
Coilcraft  
R4793-A  
Pulse  
PE-53900  
Renco  
RL-5472-5  
Schott  
67146520  
(1) 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  
(2) 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  
(3) Renco Electronics Inc.,: Phone: (800) 645-582860 Jeffryn Blvd. East, Deer Park, NY 11729: Fax: (516) 586-5562  
(4) Schott Corp.,: Phone: (612) 475-11731000 Parkers Lane Road, Wayzata, MN 55391: Fax: (612) 475-1786  
Figure 51. +12V to +24V Boost Regulator  
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Figure 52. +24V to +36V Boost Regulator  
*The LM2588 will require 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 the Application Hints.  
Figure 53. +24V to +48V Boost Regulator  
Application Hints  
LM2588 SPECIAL FEATURES  
Figure 54. Shutdown Operation  
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 54).  
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The device will shut down when 3V or greater is applied on the ON /OFF pin, sourcing current into pin 1. In shut  
down mode, the device will draw 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 54 (for normal  
operation, do not source or sink current to or from this pin—see the next section).  
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 54, 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 4 shows resistor values corresponding to commonly used frequencies.  
However, changing the LM2588's operating frequency from its nominal value of 100 kHz will change the  
magnetics selection and compensation component values.  
Table 4. Frequency Setting Resistor Guide  
RSET(kΩ)  
Open  
200  
Frequency (kHz)  
100  
125  
150  
175  
200  
47  
33  
22  
Figure 55. Frequency Synchronization  
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 55 and Figure 56).  
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.  
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Figure 56. Waveforms of a Synchronized  
12V Boost Regulator  
The scope photo in Figure 56 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.  
PROGRAMMING OUTPUT VOLTAGE  
(SELECTING R1 AND R2)  
Referring to the adjustable regulator in Figure 57, 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 1.23V internal  
reference. With R2 between 1k and 5k, R1 is:  
R1 = R2 (VOUT/VREF 1)  
where VREF = 1.23V  
(2)  
For best temperature coefficient and stability with time, use 1% metal film resistors.  
SHORT CIRCUIT CONDITION  
Due to the inherent nature of boost regulators, when the output is shorted (see Figure 57 ), 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 5A.  
In a flyback regulator application (Figure 58 ), using the standard transformers, the LM2588 will survive 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.  
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Figure 57. Boost Regulator  
Figure 58. Flyback Regulator  
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 58). 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 recitified 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 1.0 μF ceramic capacitor between VIN and ground as close as possible to the device.  
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 (Max):  
VSW(OFF) = VIN (Max) + (VOUT +VF)/N  
(3)  
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where VF is the forward biased voltage of the output diode, and is typically 0.5V for Schottky diodes and 0.8V for  
ultra-fast recovery diodes. In certain circuits, there exists a voltage spike, VLL, superimposed on top of the  
steady-state voltage (see Figure 21, 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 20 and other flyback regulator circuits throughout the datasheet). The schematic in  
Figure 58 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 CIRCUIT LAYOUT GUIDELINES 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 58. The values of the  
resistor and the capacitor must be chosen so that the voltage at the Switch pin does not drop below 0.4V. 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 58. This prevents the voltage at pin 5 from dropping below 0.4V. The reverse  
voltage rating of the diode must be greater than the switch off voltage.  
Figure 59. Input Line Filter  
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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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 59 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).  
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:  
(6)  
where VSAT is the switch saturation voltage and can be found in the Characteristic Curves.  
Figure 60. Circuit Board Layout  
CIRCUIT 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 60).  
When using the Adjustable version, physically locate the programming resistors as near the regulator IC as  
possible, to keep the sensitive feedback wiring short.  
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:  
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(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:  
(8)  
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.  
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.  
To further simplify the flyback regulator design procedure, Texas Instruments is making available computer  
design software Switchers Made Simple™. Software is available on a (3½) diskette for IBM compatible  
computers from a Texas Instruments sales office in your area or the Texas Instruments Customer Response  
Center (1-800-272-9959).  
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REVISION HISTORY  
Changes from Revision C (April 2013) to Revision D  
Page  
Changed layout of National Data Sheet to TI format .......................................................................................................... 30  
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PACKAGE OPTION ADDENDUM  
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1-Nov-2013  
PACKAGING INFORMATION  
Orderable Device  
LM2588S-12/NOPB  
LM2588S-3.3/NOPB  
LM2588S-5.0/NOPB  
LM2588S-ADJ  
Status Package Type Package Pins Package  
Eco Plan  
Lead/Ball Finish  
MSL Peak Temp  
Op Temp (°C)  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
Device Marking  
Samples  
Drawing  
Qty  
(1)  
(2)  
(6)  
(3)  
(4/5)  
ACTIVE  
DDPAK/  
TO-263  
KTW  
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
45  
Pb-Free (RoHS  
Exempt)  
CU SN  
CU SN  
CU SN  
Call TI  
CU SN  
CU SN  
CU SN  
Call TI  
CU SN  
CU SN  
CU SN  
Call TI  
CU SN  
Call TI  
CU SN  
Level-3-245C-168 HR  
Level-3-245C-168 HR  
Level-3-245C-168 HR  
Call TI  
LM2588S  
-12 P+  
ACTIVE  
ACTIVE  
NRND  
DDPAK/  
TO-263  
KTW  
KTW  
KTW  
KTW  
KTW  
KTW  
KTW  
KTW  
KTW  
NDZ  
NDZ  
NDZ  
NDZ  
NDZ  
45  
45  
Pb-Free (RoHS  
Exempt)  
LM2588S  
-3.3 P+  
DDPAK/  
TO-263  
Pb-Free (RoHS  
Exempt)  
LM2588S  
-5.0 P+  
DDPAK/  
TO-263  
45  
TBD  
LM2588S  
-ADJ P+  
LM2588S-ADJ/NOPB  
LM2588SX-12/NOPB  
LM2588SX-3.3/NOPB  
LM2588SX-5.0  
ACTIVE  
ACTIVE  
ACTIVE  
NRND  
DDPAK/  
TO-263  
45  
Pb-Free (RoHS  
Exempt)  
Level-3-245C-168 HR  
Level-3-245C-168 HR  
Level-3-245C-168 HR  
Call TI  
LM2588S  
-ADJ P+  
DDPAK/  
TO-263  
500  
500  
500  
500  
500  
45  
Pb-Free (RoHS  
Exempt)  
LM2588S  
-12 P+  
DDPAK/  
TO-263  
Pb-Free (RoHS  
Exempt)  
LM2588S  
-3.3 P+  
DDPAK/  
TO-263  
TBD  
LM2588S  
-5.0 P+  
LM2588SX-5.0/NOPB  
LM2588SX-ADJ/NOPB  
LM2588T-3.3/NOPB  
LM2588T-5.0  
ACTIVE  
ACTIVE  
ACTIVE  
NRND  
DDPAK/  
TO-263  
Pb-Free (RoHS  
Exempt)  
Level-3-245C-168 HR  
Level-3-245C-168 HR  
Level-1-NA-UNLIM  
Call TI  
LM2588S  
-5.0 P+  
DDPAK/  
TO-263  
Pb-Free (RoHS  
Exempt)  
LM2588S  
-ADJ P+  
TO-220  
TO-220  
TO-220  
TO-220  
TO-220  
Pb-Free (RoHS  
Exempt)  
LM2588T  
-3.3 P+  
45  
TBD  
LM2588T  
-5.0 P+  
LM2588T-5.0/NOPB  
LM2588T-ADJ  
ACTIVE  
NRND  
45  
Pb-Free (RoHS  
Exempt)  
Level-1-NA-UNLIM  
Call TI  
LM2588T  
-5.0 P+  
45  
TBD  
LM2588T  
-ADJ P+  
LM2588T-ADJ/NOPB  
ACTIVE  
45  
Pb-Free (RoHS  
Exempt)  
Level-1-NA-UNLIM  
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.  
Addendum-Page 1  
PACKAGE OPTION ADDENDUM  
www.ti.com  
1-Nov-2013  
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) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability  
information and additional product content details.  
TBD: The Pb-Free/Green conversion plan has not been defined.  
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that  
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.  
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between  
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.  
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight  
in homogeneous material)  
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.  
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.  
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation  
of the previous line and the two combined represent the entire Device Marking for that device.  
(6) Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish  
value exceeds the maximum column width.  
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information  
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and  
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.  
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.  
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.  
Addendum-Page 2  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
23-Sep-2013  
TAPE AND REEL INFORMATION  
*All dimensions are nominal  
Device  
Package Package Pins  
Type Drawing  
SPQ  
Reel  
Reel  
A0  
B0  
K0  
P1  
W
Pin1  
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant  
(mm) W1 (mm)  
LM2588SX-12/NOPB  
LM2588SX-3.3/NOPB  
LM2588SX-5.0  
DDPAK/  
TO-263  
KTW  
KTW  
KTW  
KTW  
KTW  
7
7
7
7
7
500  
500  
500  
500  
500  
330.0  
330.0  
330.0  
330.0  
330.0  
24.4  
24.4  
24.4  
24.4  
24.4  
10.75 14.85  
10.75 14.85  
10.75 14.85  
10.75 14.85  
10.75 14.85  
5.0  
5.0  
5.0  
5.0  
5.0  
16.0  
16.0  
16.0  
16.0  
16.0  
24.0  
24.0  
24.0  
24.0  
24.0  
Q2  
Q2  
Q2  
Q2  
Q2  
DDPAK/  
TO-263  
DDPAK/  
TO-263  
LM2588SX-5.0/NOPB  
DDPAK/  
TO-263  
LM2588SX-ADJ/NOPB DDPAK/  
TO-263  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
23-Sep-2013  
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
SPQ  
Length (mm) Width (mm) Height (mm)  
LM2588SX-12/NOPB  
LM2588SX-3.3/NOPB  
LM2588SX-5.0  
DDPAK/TO-263  
DDPAK/TO-263  
DDPAK/TO-263  
DDPAK/TO-263  
DDPAK/TO-263  
KTW  
KTW  
KTW  
KTW  
KTW  
7
7
7
7
7
500  
500  
500  
500  
500  
367.0  
367.0  
367.0  
367.0  
367.0  
367.0  
367.0  
367.0  
367.0  
367.0  
45.0  
45.0  
45.0  
45.0  
45.0  
LM2588SX-5.0/NOPB  
LM2588SX-ADJ/NOPB  
Pack Materials-Page 2  
MECHANICAL DATA  
NDZ0007B  
TA07B (Rev E)  
www.ti.com  
MECHANICAL DATA  
KTW0007B  
TS7B (Rev E)  
BOTTOM SIDE OF PACKAGE  
www.ti.com  
IMPORTANT NOTICE  
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, enhancements, improvements and other  
changes to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest  
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complete. All semiconductor products (also referred to herein as “components”) are sold subject to TI’s terms and conditions of sale  
supplied at the time of order acknowledgment.  
TI warrants performance of its components to the specifications applicable at the time of sale, in accordance with the warranty in TI’s terms  
and conditions of sale of semiconductor products. Testing and other quality control techniques are used to the extent TI deems necessary  
to support this warranty. Except where mandated by applicable law, testing of all parameters of each component is not necessarily  
performed.  
TI assumes no liability for applications assistance or the design of Buyers’ products. Buyers are responsible for their products and  
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TI does not warrant or represent that any license, either express or implied, is granted under any patent right, copyright, mask work right, or  
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