NSC LM2597M-12, LM2597HVN-5.0, LM2597HVN-3.3, LM2597HVN-12, LM2597HVMX-ADJ Datasheet

March 1998

LM2597/LM2597HV

SIMPLE SWITCHER® Power Converter 150 kHz 0.5A Step-Down Voltage Regulator, with Features

General Description

The LM2597/LM2597HV series of regulators are monolithic integrated circuits that provide all the active functions for a step-down (buck) switching regulator, capable of driving a 0.5A load with excellent line and load regulation. These devices are available in fixed output voltages of 3.3V, 5V, 12V, and an adjustable output version, and are packaged in an 8-lead DIP and an 8-lead surface mount package.

This series of switching regulators is similar to the LM2594 series, with additional supervisory and performance features added.

Requiring a minimum number of external components, these regulators are simple to use and include internal frequency compensation², improved line and load specifications, fixed-frequency oscillator, Shutdown /Soft-start, error flag delay and error flag output.

The LM2597/LM2597HV series operates at a switching frequency of 150 kHz thus allowing smaller sized filter components than what would be needed with lower frequency switching regulators. Because of its high efficiency, the copper traces on the printed circuit board are normally the only heat sinking needed.

A standard series of inductors (both through hole and surface mount types) are available from several different manufacturers optimized for use with the LM2597/LM2597HV series. This feature greatly simplifies the design of switch-mode power supplies.

Other features include a guaranteed ±4% tolerance on output voltage under all conditions of input voltage and output load conditions, and ±15% on the oscillator frequency. External shutdown is included, featuring typically 85 µA standby current. Self protection features include a two stage current limit for the output switch and an over temperature shutdown for complete protection under fault conditions.

The LM2597HV is for use in applications requiring and input voltage up to 60V.

Features

n3.3V, 5V, 12V, and adjustable output versions

nAdjustable version output voltage range, 1.2V to 37V (57V for HV version)±4% max over line and load conditions

nGuaranteed 0.5A output current

nAvailable in 8-pin surface mount and DIP-8 package

nInput voltage range up to 60V

n150 kHz fixed frequency internal oscillator

nShutdown /Soft-start

nOut of regulation error flag

nError output delay

nBias Supply Pin (VBS) for internal circuitry improves efficiency at high input voltages

nLow power standby mode, IQ typically 85 µA

nHigh Efficiency

nUses readily available standard inductors

nThermal shutdown and current limit protection

Applications

nSimple high-efficiency step-down (buck) regulator

nEfficient pre-regulator for linear regulators

nOn-card switching regulators

nPositive to Negative converter

Typical Application (Fixed Output Voltage Versions)

DS012440-1

²Patent Number 5,382,918.

SIMPLE SWITCHER® and Switchers Made Simple ® are registered trademarks of National Semiconductor Corporation.

Voltage Down-Step 5A.0 kHz 150 Converter Power SWITCHER SIMPLE LM2597/LM2597HV

Features with Regulator,

© 1999 National Semiconductor Corporation

DS012440

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Absolute Maximum Ratings (Note 1)

If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications.

Maximum Supply Voltage (VIN)
		LM2597		45V
		LM2597HV		60V
				6V
	SD	/SS Pin Input Voltage (Note 2)
Delay Pin Voltage (Note 2)				1.5V
Flag Pin Voltage			−0.3	≤ V ≤45V
Bias Supply Voltage (VBS)			−0.3	≤ V ≤30V
	Feedback Pin Voltage		−0.3	≤ V ≤+25V
	Output Voltage to Ground
	(Steady State)			−1V
	Power Dissipation		Internally limited
	Storage Temperature Range		−65ÊC to +150ÊC

ESD Susceptibility
Human Body Model (Note 3)	2 kV
Lead Temperature
M8 Package
Vapor Phase (60 sec.)	+215ÊC
Infrared (15 sec.)	+220ÊC
N Package (Soldering, 10 sec.)	+260ÊC
Maximum Junction Temperature	+150ÊC

Operating Conditions

Temperature Range	−40ÊC ≤ TJ +125ÊC
Supply Voltage
LM2597	4.5V to 40V
LM2597HV	4.5V to 60V

LM2597/LM2597HV-3.3

Electrical Characteristics

Specifications with standard type face are for TJ = 25ÊC, and those with boldface type apply over full Operating Temperature Range.VINmax=40V for the LM2597 and 60V for the LM2597HV

Symbol	Parameter	Conditions	LM2597/LM2597HV-3.3		Units
					(Limits)
			Typ	Limit
			(Note 4)	(Note 5)
SYSTEM PARAMETERS (Note 6) Test Circuit Figure 12
VOUT	Output Voltage	4.75V ≤ VIN ≤ VINmax, 0.1A ≤ ILOAD ≤ 0.5A	3.3		V
				3.168/3.135	V(min)
				3.432/3.465	V(max)
η	Efficiency	VIN = 12V, ILOAD = 0.5A	80		%

LM2597/LM2597HV-5.0

Electrical Characteristics

Specifications with standard type face are for TJ = 25ÊC, and those with boldface type apply over full Operating Temperature Range.VINmax=40V for the LM2597 and 60V for the LM2597HV

Symbol	Parameter	Conditions	LM2597/LM2597HV-5.0		Units
					(Limits)
			Typ	Limit
			(Note 4)	(Note 5)
SYSTEM PARAMETERS (Note 6) Test Circuit Figure 12
VOUT	Output Voltage	7V ≤ VIN ≤ VINmax, 0.1A ≤ ILOAD ≤ 0.5A	5		V
				4.800/4.750	V(min)
				5.200/5.250	V(max)
η	Efficiency	VIN = 12V, ILOAD = 0.5A	82		%

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LM2597/LM2597HV-12

Electrical Characteristics

Specifications with standard type face are for TJ = 25ÊC, and those with boldface type apply over full Operating Temperature Range.VINmax=40V for the LM2597 and 60V for the LM2597HV

Symbol	Parameter	Conditions	LM2597/LM2597HV-12		Units
					(Limits)
			Typ	Limit
			(Note 4)	(Note 5)
SYSTEM PARAMETERS (Note 6) Test Circuit Figure 12
VOUT	Output Voltage	15V ≤ VIN ≤ VINmax, 0.1A ≤ ILOAD ≤ 0.5A	12		V
				11.52/11.40	V(min)
				12.48/12.60	V(max)
η	Efficiency	VIN = 25V, ILOAD = 0.5A	88		%

LM2597/LM2597HV-ADJ

Electrical Characteristics

Specifications with standard type face are for TJ = 25ÊC, and those with boldface type apply over full Operating Temperature Range.VINmax=40V for the LM2597 and 60V for the LM2597HV

Symbol	Parameter	Conditions	LM2597/LM2597HV-ADJ		Units
					(Limits)
			Typ	Limit
			(Note 4)	(Note 5)
SYSTEM PARAMETERS (Note 6) Test Circuit Figure 12
VFB	Feedback Voltage	4.5V ≤ VIN ≤ VINmax, 0.1A ≤ ILOAD ≤ 0.5A	1.230		V
		VOUT programmed for 3V. Circuit of Figure 12.		1.193/1.180	V(min)
				1.267/1.280	V(max)
η	Efficiency	VIN = 12V, VOUT = 3V, ILOAD = 0.5A	80		%

All Output Voltage Versions

Electrical Characteristics

Specifications with standard type face are for TJ = 25ÊC, and those with boldface type apply over full Operating Temperature Range. Unless otherwise specified, VIN = 12V for the 3.3V, 5V, and Adjustable version and VIN = 24V for the 12V version. ILOAD = 100 mA.

Symbol	Parameter			Conditions		LM2597/LM2597HV-XX		Units
								(Limits)
						Typ	Limit
						(Note 4)	(Note 5)
DEVICE PARAMETERS
Ib	Feedback Bias Current		Adjustable Version Only, VFB = 1.235V			10	50/100	nA
fO	Oscillator Frequency		(Note 7)			150		kHz
							127/110	kHz(min)
							173/173	kHz(max)
VSAT	Saturation Voltage		IOUT = 0.5A (Notes 8 and 9)			0.9		V
							1.1/1.2	V(max)
DC	Max Duty Cycle (ON)	(Note 9)				100		%
	Min Duty Cycle (OFF)	(Note 10)				0
ICL	Current Limit		Peak Current, (Notes 8 and 9)			0.8		A
							0.65/0.58	A(min)
							1.3/1.4	A(max)
IL	Output Leakage Current		(Notes 8, 10 and 11)		Output = 0V		50	µA(max)
			Output = −1V			2		mA
							15	mA(max)
IQ	Operating Quiescent					5		mA
			SD	/SS Pin Open, VBS Pin Open(Note 10)
	Current						10	mA(max)

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All Output Voltage Versions

Electrical Characteristics (Continued)

Specifications with standard type face are for TJ = 25ÊC, and those with boldface type apply over full Operating Temperature Range. Unless otherwise specified, VIN = 12V for the 3.3V, 5V, and Adjustable version and VIN = 24V for the 12V version. ILOAD = 100 mA.

Symbol	Parameter						Conditions		LM2597/LM2597HV-XX		Units
											(Limits)
									Typ	Limit
									(Note 4)	(Note 5)
DEVICE PARAMETERS
ISTBY	Standby Quiescent		SD		/SS pin = 0V			(Note 10)LM2597	85		µA
	Current									200/250	µA(max)
							LM2597HV		140	250/300	µA(max)
θJA	Thermal Resistance		N Package, Junction to Ambient (Note 12)						95		ÊC/W
			M Package, Junction to Ambient (Note 12)						150
SHUTDOWN/SOFT-START CONTROL Test Circuit of Figure 12
VSD	Shutdown Threshold								1.3		V
	Voltage		Low, (Shutdown Mode)							0.6	V(max)
			High, (Soft-start Mode)							2	V(min)
VSS	Soft-start Voltage		VOUT = 20% of Nominal Output Voltage						2		V
			VOUT = 100% of Nominal Output Voltage						3
ISD	Shutdown Current		V			= 0.5V			5		µA
				SHUTDOWN
										10	µA(max)
ISS	Soft-start Current		VSoft-start = 2.5V						1.6		µA
										5	µA(max)
FLAG/DELAY CONTROL Test Circuit of Figure 12
	Regulator Dropout		Low (Flag ON)						96		%
	Detector									92	%(min)
	Threshold Voltage									98	%(max)
VFSAT	Flag Output Saturation		ISINK = 3 mA						0.3		V
	Voltage	VDELAY = 0.5V								0.7/1.0	V(max)
IFL	Flag Output Leakage		VFLAG = 40V						0.3		µA
	Current
	Delay Pin Threshold								1.25		V
	Voltage	Low (Flag ON)								1.21	V(min)
		High (Flag OFF) and VOUT Regulated								1.29	V(max)
	Delay Pin Source	VDELAY = 0.5V							3		µA
	Current									6	µA(max)
	Delay Pin Saturation	Low (Flag ON)							55		mV
										350/400	mV(max)
BIAS SUPPLY
IBS	Bias Supply Pin Current		VBS = 2V				(Note 10)		120		µA
										400	µA(max)
			VBS = 4.4V (Note 10)						4		mA
										10	mA(max)
IQ	Operating Quiescent		VBS = 4.4V , Vin pin current(Note 10)						1	2	mA
	Current

Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is intended to be functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics.

Note 2: Voltage internally clamped. If clamp voltage is exceeded, limit current to a maximum of 1 mA.

Note 3: The human body model is a 100 pF capacitor discharged through a 1.5k resistor into each pin.

Note 4: Typical numbers are at 25ÊC and represent the most likely norm.

Note 5: All limits guaranteed at room temperature (standard type face) and at temperature extremes (bold type face). All room temperature limits are 100% production tested. All limits at temperature extremes are guaranteed via correlation using standard Statistical Quality Control (SQC) methods. All limits are used to calculate Average Outgoing Quality Level (AOQL).

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All Output Voltage Versions

Electrical Characteristics (Continued)

Note 6: External components such as the catch diode, inductor, input and output capacitors can affect switching regulator system performance. When the LM2597/ LM2597HV is used as shown in the Figure 12 test circuit, system performance will be as shown in system parameters section of Electrical Characteristics.

Note 7: The switching frequency is reduced when the second stage current limit is activated. The amount of reduction is determined by the severity of current overload.

Note 8: No diode, inductor or capacitor connected to output pin.

Note 9: Feedback pin removed from output and connected to 0V to force the output transistor switch ON.

Note 10: Feedback pin removed from output and connected to 12V for the 3.3V, 5V, and the ADJ. version, and 15V for the 12V version, to force the output transistor switch OFF.

Note 11: VIN = 40V for the LM2597 and 60V for the LM2597HV.

Note 12: Junction to ambient thermal resistance with approximately 1 square inch of printed circuit board copper surrounding the leads. Additional copper area will lower thermal resistance further. See application hints in this data sheet and the thermal model in Switchers Made Simple ™ software.

Typical Performance Characteristics

Normalized	Line Regulation	Efficiency
Output Voltage

	DS012440-3	DS012440-4
	DS012440-2
Switch Saturation	Switch Current Limit	Dropout Voltage
Voltage

	DS012440-6	DS012440-7
	DS012440-5
Quiescent Current	Standby	Minimum Operating
	Quiescent Current	Supply Voltage

DS012440-8

DS012440-9

DS012440-10

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Typical Performance Characteristics (Continued)

Feedback Pin	Flag Saturation	Switching Frequency
Bias Current	Voltage

DS012440-13

DS012440-11			DS012440-12
Soft-start	Shutdown /Soft-start		Delay Pin Current
	Current

	DS012440-14			DS012440-16
		DS012440-15
VIN and VBS Current vs	Soft-start Response		Shutdown /Soft-start
VBS and Temperature			Threshold Voltage

DS012440-18

DS012440-17

DS012440-25

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Typical Performance Characteristics (Continued)

Continuous Mode Switching Waveforms	Discontinuous Mode Switching Waveforms
VIN = 20V, VOUT = 5V, ILOAD = 400 mA
L = 100 µH, C OUT = 120 µF, C OUT ESR = 140 mΩ	VIN = 20V, VOUT = 5V, ILOAD = 200 mA
	L = 33 µH, C OUT = 220 µF, C OUT ESR = 60 mΩ

DS012440-19

A:Output Pin Voltage, 10V/div.

B:Inductor Current 0.2A/div.

C:Output Ripple Voltage, 20 mV/div.

Horizontal Time Base: 2 µs/div.

Load Transient Response for Continuous Mode

VIN = 20V, VOUT = 5V, ILOAD = 200 mA to 500 mA L = 100 µH, C OUT = 120 µF, C OUT ESR = 140 mΩ

DS012440-21

A:Output Voltage, 50 mV/div. (AC)

B:200 mA to 500 mA Load Pulse

Horizontal Time Base: 50 µs/div.

DS012440-20

A:Output Pin Voltage, 10V/div.

B:Inductor Current 0.2A/div.

C:Output Ripple Voltage, 20 mV/div.

Horizontal Time Base: 2 µs/div.

Load Transient Response for Discontinuous Mode

VIN = 20V, VOUT = 5V, ILOAD = 100 mA to 200 mA L = 33 µH, C OUT = 220 µF, C OUT ESR = 60 mΩ

DS012440-22

A:Output Voltage, 50 mV/div. (AC)

B:100 mA to 200 mA Load Pulse

Horizontal Time Base: 200 µs/div.

Connection Diagrams and Ordering Information

8±Lead DIP (N)

8±Lead Surface Mount (M)

DS012440-23

DS012440-24

Top View

Order Number LM2597N-3.3,

Top View

LM2597N-5.0, LM2597N-12 or

Order Number LM2597M-3.3,

LM2597N-ADJ

LM2597M-5.0, LM2597M-12 or

LM2597HVN-3.3, LM2597HVN-5.0,

LM2597M-ADJ

LM2597HVN-12 or LM2597HVN-ADJ

LM2597HVM-3.3, LM2597HVM-5.0,

See NS Package Number N08E

LM2597HVM-12 or LM2597HVM-ADJ

See NS Package Number M08A

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LM2597/LM2597HV Series Buck Regulator Design Procedure (Fixed

Output)

	PROCEDURE (Fixed Output Voltage Version)	EXAMPLE (Fixed Output Voltage Version)
	Given:	Given:
	VOUT = Regulated Output Voltage (3.3V, 5V or 12V)	VOUT = 5V
	VIN(max) = Maximum DC Input Voltage	VIN(max) = 12V
	ILOAD(max) = Maximum Load Current	ILOAD(max) = 0.4A
	1. Inductor Selection (L1)	1. Inductor Selection (L1)
	A. Select the correct inductor value selection guide from Fig-	A. Use the inductor selection guide for the 5V version shown
	ure 3, Figure 4, or Figure 5. (Output voltages of 3.3V, 5V, or	in Figure 4.
	12V respectively.) For all other voltages, see the design pro-	B. From the inductor value selection guide shown in Figure 4,
	cedure for the adjustable version.	the inductance region intersected by the 12V horizontal line
	B. From the inductor value selection guide, identify the induc-	and the 0.4A vertical line is 100 µH, and the inductor code is
	tance region intersected by the Maximum Input Voltage line	L20.
	and the Maximum Load Current line. Each region is identified	C. The inductance value required is 100 µH. From the table in
	by an inductance value and an inductor code (LXX).	Figure 7, go to the L20 line and choose an inductor part num-
	C. Select an appropriate inductor from the four manufacturer's	ber from any of the four manufacturers shown. (In most in-
	part numbers listed in Figure 7.	stance, both through hole and surface mount inductors are
		available.)
	2. Output Capacitor Selection (COUT)	2. Output Capacitor Selection (COUT)
	A. In the majority of applications, low ESR (Equivalent Series	A. See section on output capacitors in application infor-
	Resistance) electrolytic capacitors between 82 µF and 220 µF	mation section.
	and low ESR solid tantalum capacitors between 15 µF and	B. From the quick design component selection table shown in
	100 µF provide the best results. This capacitor should be lo-	Figure 1, locate the 5V output voltage section. In the load cur-
	cated close to the IC using short capacitor leads and short
		rent column, choose the load current line that is closest to the
	copper traces. Do not use capacitors larger than 220 µF.
		current needed in your application, for this example, use the
	For additional information, see section on output capaci-	0.5A line. In the maximum input voltage column, select the
	tors in application information section.	line that covers the input voltage needed in your application,
	B. To simplify the capacitor selection procedure, refer to the	in this example, use the 15V line. Continuing on this line are
	quick design component selection table shown in Figure 1.	recommended inductors and capacitors that will provide the
	This table contains different input voltages, output voltages,	best overall performance.
	and load currents, and lists various inductors and output ca-	The capacitor list contains both through hole electrolytic and
	pacitors that will provide the best design solutions.	surface mount tantalum capacitors from four different capaci-
	C. The capacitor voltage rating for electrolytic capacitors	tor manufacturers. It is recommended that both the manufac-
	should be at least 1.5 times greater than the output voltage,	turers and the manufacturer's series that are listed in the table
		be used.
	and often much higher voltage ratings are needed to satisfy
	the low ESR requirements for low output ripple voltage.	In this example aluminum electrolytic capacitors from several
	D. For computer aided design software, see Switchers Made	different manufacturers are available with the range of ESR
	Simple® version 4.1 or later).	numbers needed.
		120 µF	25V	Panasonic HFQ Series
		120 µF	25V	Nichicon PL Series
		C. For a 5V output, a capacitor voltage rating at least 7.5V or
		more is needed. But, in this example, even a low ESR, switch-
		ing grade, 120 µF 10V aluminum electrolytic capacitor would
		exhibit approximately 400 mΩ of ESR (see the curve in Figure
		16 for the ESR vs voltage rating). This amount of ESR would
		result in relatively high output ripple voltage. To reduce the
		ripple to 1% of the output voltage, or less, a capacitor with a
		higher voltage rating (lower ESR) should be selected. A 16V
		or 25V capacitor will reduce the ripple voltage by approxi-
		mately half.

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LM2597/LM2597HV Series Buck Regulator Design Procedure (Fixed

Output) (Continued)

PROCEDURE (Fixed Output Voltage Version)	EXAMPLE (Fixed Output Voltage Version)
3. Catch Diode Selection (D1)	3. Catch Diode Selection (D1)
A. The catch diode current rating must be at least 1.3 times	A. Refer to the table shown in Figure 10. In this example, a
greater than the maximum load current. Also, if the power	1A, 20V, 1N5817 Schottky diode will provide the best perfor-
supply design must withstand a continuous output short, the	mance, and will not be overstressed even for a shorted out-
diode should have a current rating equal to the maximum cur-	put.
rent limit of the LM2597. The most stressful condition for this
diode is an overload or shorted output condition.

B.The reverse voltage rating of the diode should be at least 1.25 times the maximum input voltage.

C.This diode must be fast (short reverse recovery time) and must be located close to the LM2597 using short leads and short printed circuit traces. Because of their fast switching speed and low forward voltage drop, Schottky diodes provide the best performance and efficiency, and should be the first choice, especially in low output voltage applications. Ultra-fast recovery, or High-Efficiency rectifiers also provide good results. Ultra-fast recovery diodes typically have reverse recovery times of 50 ns or less. Rectifiers such as the 1N4001 series are much too slow and should not be used.

	4. Input Capacitor (CIN)	4. Input Capacitor (CIN)
	A low ESR aluminum or tantalum bypass capacitor is needed	The important parameters for the Input capacitor are the input
	between the input pin and ground to prevent large voltage	voltage rating and the RMS current rating. With a nominal in-
	transients from appearing at the input. In addition, the RMS	put voltage of 12V, an aluminum electrolytic capacitor with a
	current rating of the input capacitor should be selected to be	voltage rating greater than 18V (1.5 x VIN) would be needed.
	at least 1¤2 the DC load current. The capacitor manufacturers	The next higher capacitor voltage rating is 25V.
	data sheet must be checked to assure that this current rating	The RMS current rating requirement for the input capacitor in
	is not exceeded. The curve shown in Figure 15 shows typical	a buck regulator is approximately 1¤2 the DC load current. In
	RMS current ratings for several different aluminum electrolytic	this example, with a 400 mA load, a capacitor with a RMS cur-
	capacitor values.	rent rating of at least 200 mA is needed. The curves shown in
	This capacitor should be located close to the IC using short	Figure 15 can be used to select an appropriate input capaci-
	leads and the voltage rating should be approximately 1.5	tor. From the curves, locate the 25V line and note which ca-
	times the maximum input voltage.	pacitor values have RMS current ratings greater than 200 mA.
	If solid tantalum input capacitors are used, it is recommended	Either a 47 µF or 68 µF, 25V capacitor could be used.
	that they be surge current tested by the manufacturer.	For a through hole design, a 68 µF/25V electrolytic capacitor
	Use caution when using ceramic capacitors for input bypass-	(Panasonic HFQ series or Nichicon PL series or equivalent)
	ing, because it may cause severe ringing at the VIN pin.	would be adequate. Other types or other manufacturers ca-
	For additional information, see section on input capaci-	pacitors can be used provided the RMS ripple current ratings
		are adequate.
	tors in Application Information section.
		For surface mount designs, solid tantalum capacitors are rec-
		ommended. The TPS series available from AVX, and the
		593D series from Sprague are both surge current tested.

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LM2597/LM2597HV Series Buck Regulator Design Procedure (Fixed

Output) (Continued)

	Conditions			Inductor			Output Capacitor
						Through Hole		Surface Mount
Output	Load		Max Input	Inductance	Inductor	Panasonic	Nichicon	AVX TPS	Sprague
Voltage	Current		Voltage	(µH)	( #)	HFQ Series	PL Series	Series	595D Series
(V)	(A)		(V)			(µF/V)	(µF/V)	(µF/V)	(µF/V)
3.3	0.5		5	33	L14	220/16	220/16	100/16	100/6.3
			7	47	L13	120/25	120/25	100/16	100/6.3
			10	68	L21	120/25	120/25	100/16	100/6.3
			40	100	L20	120/35	120/35	100/16	100/6.3
			6	68	L4	120/25	120/25	100/16	100/6.3
	0.2		10	150	L10	120/16	120/16	100/16	100/6.3
			40	220	L9	120/16	120/16	100/16	100/6.3
5	0.5		8	47	L13	180/16	180/16	100/16	33/25
			10	68	L21	180/16	180/16	100/16	33/25
			15	100	L20	120/25	120/25	100/16	33/25
			40	150	L19	120/25	120/25	100/16	33/25
			9	150	L10	82/16	82/16	100/16	33/25
	0.2		20	220	L9	120/16	120/16	100/16	33/25
			40	330	L8	120/16	120/16	100/16	33/25
12	0.5		15	68	L21	82/25	82/25	100/16	15/25
			18	150	L19	82/25	82/25	100/16	15/25
			30	220	L27	82/25	82/25	100/16	15/25
			40	330	L26	82/25	82/25	100/16	15/25
			15	100	L11	82/25	82/25	100/16	15/25
	0.2		20	220	L9	82/25	82/25	100/16	15/25
			40	330	L17	82/25	82/25	100/16	15/25

FIGURE 1. LM2597/LM2597HV Fixed Voltage Quick Design Component Selection Table

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