NSC LM2940S-12, LM2940S-10, LM2940IMPX-9.0, LM2940IMPX-8.0, LM2940IMPX-5.0 Datasheet

March 2000

LM2940/LM2940C

1A Low Dropout Regulator

General Description

The LM2940/LM2940C positive voltage regulator features the ability to source 1A of output current with a dropout voltage of typically 0.5V and a maximum of 1V over the entire temperature range. Furthermore, a quiescent current reduction circuit has been included which reduces the ground current when the differential between the input voltage and the output voltage exceeds approximately 3V. The quiescent current with 1A of output current and an input-output differential of 5V is therefore only 30 mA. Higher quiescent currents only exist when the regulator is in the dropout mode (VIN − V OUT ≤ 3V).

Designed also for vehicular applications, the LM2940/ LM2940C and all regulated circuitry are protected from reverse battery installations or 2-battery jumps. During line transients, such as load dump when the input voltage can

momentarily exceed the specified maximum operating voltage, the regulator will automatically shut down to protect both the internal circuits and the load. The LM2940/ LM2940C cannot be harmed by temporary mirror-image insertion. Familiar regulator features such as short circuit and thermal overload protection are also provided.

Features

nDropout voltage typically 0.5V @IO = 1A

nOutput current in excess of 1A

nOutput voltage trimmed before assembly

nReverse battery protection

nInternal short circuit current limit

nMirror image insertion protection

nP+ Product Enhancement tested

Typical Application

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*Required if regulator is located far from power supply filter.

**COUT must be at least 22 µF to maintain stability. May be increased without bound to maintain regulation during transients. Locate as close as possible to the regulator. This capacitor must be rated over the same operating temperature range as the regulator and the ESR is critical; see curve.

Ordering Information

Temperature				Output Voltage				Package
	Range
		5.0	8.0	9.0	10	12	15
0ÊC ≤ TJ ≤ 125ÊC		LM2940CT-5.0		LM2940CT-9.0		LM2940CT-12	LM2940CT-15	TO-220
		LM2940CS-5.0		LM2940CS-9.0		LM2940CS-12	LM2940CS-15	TO-263
−40ÊC	≤ TJ ≤ 125ÊC	LM2940T-5.0	LM2940T-8.0	LM2940T-9.0	LM2940T-10	LM2940T-12		TO-220
		LM2940S-5.0	LM2940S-8.0	LM2940S-9.0	LM2940S-10	LM2940S-12		TO-263
−40ÊC	≤ TJ ≤ 85ÊC	LM2940IMP-5.0	LM2940IMP-8.0	LM2940IMP-9.0	LM2940IMP-10	LM2940IMP-12	LM2940IMP-15	SOT-223
		LM2940IMPX-5.0	LM2940IMPX-8.0	LM2940IMPX-9.0	LM2940IMPX-10	LM2940IMPX-12	LM2940IMPX-15	SOT-223
								in Tape
								and Reel
SOT-223 Package		L53B	L54B	L0EB	L55B	L56B	L70B
	Marking

The physical size of the SOT-223 is too small to contain the full device part number. The package markings indicated are what will appear on the actual device.

Temperature		Output Voltage			Package
Range
	5.0	8.0	12	15
−55ÊC ≤ TJ ≤ 125ÊC	LM2940J-5.0/883	LM2940J-8.0/883	LM2940J-12/883	LM2940J-15/883	J16A
	5962-8958701EA	5962-9088301QEA	5962-9088401QEA	5962-9088501QEA
	LM2940WG5.0/883				WG16A
	5962-8958701XA

For information on military temperature range products, please go to the Mil/Aero Web Site at http://www.national.com/appinfo/milaero/index.html.

Regulator Dropout Low 1A LM2940/LM2940C

© 2000 National Semiconductor Corporation

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LM2940/LM2940C

Connection Diagrams

(TO-220) Plastic Package

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Front View

Order Number LM2940CT-5.0, LM2940CT-9.0,

LM2940CT-12, LM2940CT-15, LM2940T-5.0,

LM2940T-8.0, LM2940T-9.0,

LM2940T-10 or LM2940T-12

See NS Package Number TO3B

16-Lead Dual-in-Line Package (J)

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Top View

Order Number LM2940J-5.0/883 (5962-8958701EA),

LM2940J-8.0/883 (5962-9088301QEA),

LM2940J-12/883 (5962-9088401QEA),

LM2940J-15/883 (5962-9088501QEA)

See NS Package Number J16A

(TO-263) Surface-Mount Package

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Top View

DS008822-12

Side View

Order Number LM2940CS-5.0, LM2940CS-9.0,

LM2940CS-12, LM2940CS-15,

LM2940S-5.0, LM2940S-8.0,

LM2940S-9.0, LM2940S-10 or LM2940S-12

See NS Package Number TS3B

3-Lead SOT-223

DS008822-42

Front View

Order Part Number LM2940IMP-5.0,

LM2940IMP-8.0, LM2940IMP-9.0, LM2940IMP-10, LM2940IMP-12 or LM2940IMP-15 See NS Package Number MP04A

16-Lead Ceramic Surface-Mount Package (WG)

DS008822-44

Top View

Order Number LM2940WG5.0/883 (5962-8958701XA)

See NS Package Number WG16A

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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.

LM2940S, T, MP ≤ 100 ms	60V
LM2940CS, T ≤ 1 ms	45V
Internal Power Dissipation
(Note 2)	Internally Limited
Maximum Junction Temperature	150ÊC
Storage Temperature Range	−65ÊC ≤ TJ ≤ +150ÊC
Lead Temperature, Time for Wave Soldering
TO-220 (T) Package	260ÊC, 10s

TO-263 (S) Package	260ÊC, 4s
SOT-223 (MP) Package	260ÊC, 4s
ESD Susceptibility (Note 3)	2 kV

Operating Conditions (Note 1)

Input Voltage		26V
Temperature Range
LM2940T, LM2940S	−40ÊC	≤ TJ ≤ 125ÊC
LM2940CT, LM2940CS	0ÊC ≤ TJ ≤ 125ÊC
LM2940IMP	−40ÊC	≤ TJ ≤ 85ÊC
LM2940J, LM2940WG	−55ÊC	≤ TJ ≤ 125ÊC

Electrical Characteristics

VIN = VO + 5V, IO = 1A, CO = 22 µF, unless otherwise specified. Boldface limits apply over the entire operating temperature range of the indicated device. All other specifications apply for TA = TJ = 25ÊC.

	Output Voltage (VO)			5V			8V
				LM2940	LM2940/883		LM2940	LM2940/883	Units
	Parameter	Conditions	Typ	Limit	Limit	Typ	Limit	Limit
				(Note 4)	(Note 5)		(Note 4)	(Note 5)
				6.25V ≤ VIN ≤ 26V			9.4V ≤ VIN ≤ 26V
	Output Voltage	5 mA ≤ IO ≤ 1A	5.00	4.85/4.75	4.85/4.75	8.00	7.76/7.60	7.76/7.60	VMIN
				5.15/5.25	5.15/5.25		8.24/8.40	8.24/8.40	VMAX
	Line Regulation	VO + 2V ≤ VIN ≤ 26V,	20	50	40/50	20	80	50/80	mVMAX
		IO = 5 mA
	Load Regulation	50 mA ≤ IO ≤ 1A
		LM2940, LM2940/883	35	50/80	50/100	55	80/130	80/130	mVMAX
		LM2940C	35	50		55	80
	Output	100 mADC and
	Impedance	20 mArms,	35		1000/1000	55		1000/1000	mΩ
		fO = 120 Hz
	Quiescent	VO +2V ≤ VIN ≤ 26V,
	Current	IO = 5 mA
		LM2940, LM2940/883	10	15/20	15/20	10	15/20	15/20	mAMAX
		LM2940C	10	15
		VIN = VO + 5V,	30	45/60	50/60	30	45/60	50/60	mAMAX
		IO = 1A
	Output Noise	10 Hz − 100 kHz,	150		700/ 700	240		1000/1000	µVrms
	Voltage	IO = 5 mA
	Ripple Rejection	fO = 120 Hz, 1 Vrms,
		IO = 100 mA
		LM2940	72	60/54		66	54/48		dBMIN
		LM2940C	72	60		66	54
		fO = 1 kHz, 1 Vrms,			60/50			54/48	dBMIN
		IO = 5 mA
	Long Term		20			32			mV/
	Stability								1000 Hr
	Dropout Voltage	IO = 1A	0.5	0.8/1.0	0.7/1.0	0.5	0.8/1.0	0.7/1.0	VMAX
		IO = 100 mA	110	150/200	150/200	110	150/200	150/200	mVMAX
	Short Circuit	(Note 6)	1.9	1.6	1.5/1.3	1.9	1.6	1.6/1.3	AMIN
	Current

LM2940/LM2940C

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LM2940/LM2940C

Electrical Characteristics (Continued)

VIN = VO + 5V, IO = 1A, CO = 22 µF, unless otherwise specified. Boldface limits apply over the entire operating temperature range of the indicated device. All other specifications apply for TA = TJ = 25ÊC.

	Output Voltage (VO)			5V			8V
				LM2940	LM2940/883		LM2940	LM2940/883	Units
	Parameter	Conditions	Typ	Limit	Limit	Typ	Limit	Limit
				(Note 4)	(Note 5)		(Note 4)	(Note 5)
	Maximum Line	RO = 100Ω
	Transient	LM2940, T ≤ 100 ms	75	60/60		75	60/60		VMIN
		LM2940/883, T ≤ 20 ms			40/40			40/40
		LM2940C, T ≤ 1 ms	55	45		55	45
	Reverse Polarity	RO = 100Ω
	DC Input Voltage	LM2940, LM2940/883	−30	−15/ −15	−15/ −15	−30	−15/ −15	−15/ −15	VMIN
		LM2940C	−30	−15		−30	−15
	Reverse Polarity	RO = 100Ω
	Transient Input	LM2940, T ≤ 100 ms	−75	−50/ −50		−75	−50/ −50		VMIN
	Voltage	LM2940/883, T ≤ 20 ms			−45/ −45			−45/ −45
		LM2940C, T ≤ 1 ms	−55	−45/ −45

Electrical Characteristics

VIN = VO + 5V, IO = 1A, CO = 22 µF, unless otherwise specified. Boldface limits apply over the entire operating temperature range of the indicated device. All other specifications apply for TA = TJ = 25ÊC.

	Output Voltage (VO)			9V		10V
				LM2940		LM2940	Units
	Parameter	Conditions	Typ	Limit	Typ	Limit
				(Note 4)		(Note 4)
			10.5V ≤ VIN ≤ 26V		11.5V ≤ VIN ≤ 26V
	Output Voltage	5 mA ≤ IO ≤1A	9.00	8.73/8.55	10.00	9.70/9.50	VMIN
				9.27/9.45		10.30/10.50	VMAX
	Line Regulation	VO + 2V ≤ VIN ≤ 26V,	20	90	20	100	mVMAX
		IO = 5 mA
	Load Regulation	50 mA ≤ IO ≤ 1A
		LM2940	60	90/150	65	100/165	mVMAX
		LM2940C	60	90
	Output Impedance	100 mADC and
		20 mArms,	60		65		mΩ
		fO = 120 Hz
	Quiescent	VO +2V ≤ VIN < 26V,
	Current	IO = 5 mA
		LM2940	10	15/20	10	15/20	mAMAX
		LM2940C	10	15
		VIN = VO + 5V, IO = 1A	30	45/60	30	45/60	mAMAX
	Output Noise	10 Hz − 100 kHz,	270		300		µV rms
	Voltage	IO = 5 mA
	Ripple Rejection	fO = 120 Hz, 1 Vrms,
		IO = 100 mA
		LM2940	64	52/46	63	51/45	dBMIN
		LM2940C	64	52
	Long Term		34		36		mV/
	Stability						1000 Hr
	Dropout Voltage	IO = 1A	0.5	0.8/1.0	0.5	0.8/1.0	VMAX
		IO = 100 mA	110	150/200	110	150/200	mVMAX

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Electrical Characteristics (Continued)

VIN = VO + 5V, IO = 1A, CO = 22 µF, unless otherwise specified. Boldface limits apply over the entire operating temperature range of the indicated device. All other specifications apply for TA = TJ = 25ÊC.

	Output Voltage (VO)			9V		10V
				LM2940		LM2940	Units
	Parameter	Conditions	Typ	Limit	Typ	Limit
				(Note 4)		(Note 4)
	Short Circuit	(Note 6)	1.9	1.6	1.9	1.6	AMIN
	Current
	Maximum Line	RO = 100Ω
	Transient	T ≤ 100 ms
		LM2940	75	60/60	75	60/60	VMIN
		LM2940C	55	45
	Reverse Polarity	RO = 100Ω
	DC Input Voltage	LM2940	−30	−15/ −15	−30	−15/ −15	VMIN
		LM2940C	−30	−15
	Reverse Polarity	RO = 100Ω
	Transient Input	T ≤ 100 ms
	Voltage	LM2940	−75	−50/ −50	−75	−50/ −50	VMIN
		LM2940C	−55	−45/ −45

Electrical Characteristics

VIN = VO + 5V, IO = 1A, CO = 22 µF, unless otherwise specified. Boldface limits apply over the entire operating temperature range of the indicated device. All other specifications apply for TA = TJ = 25ÊC.

	Output Voltage (VO)			12V			15V
				LM2940	LM2940/833		LM2940	LM2940/833	Units
	Parameter	Conditions	Typ	Limit	Limit	Typ	Limit	Limit
				(Note 4)	(Note 5)		(Note 4)	(Note 5)
				13.6V ≤ VIN ≤ 26V			16.75V ≤ VIN ≤ 26V
	Output Voltage	5 mA ≤ IO ≤1A	12.00	11.64/11.40	11.64/11.40	15.00	14.55/14.25	14.55/14.25	VMIN
				12.36/12.60	12.36/12.60		15.45/15.75	15.45/15.75	VMAX
	Line Regulation	VO + 2V ≤ VIN ≤ 26V,	20	120	75/120	20	150	95/150	mVMAX
		IO = 5 mA
	Load Regulation	50 mA ≤ IO ≤ 1A
		LM2940, LM2940/883	55	120/200	120/190			150/240	mVMAX
		LM2940C	55	120		70	150
	Output	100 mADC and
	Impedance	20 mArms,	80		1000/1000	100		1000/1000	mΩ
		fO = 120 Hz
	Quiescent	VO +2V ≤ VIN ≤ 26V,
	Current	IO = 5 mA
		LM2940, LM2940/883	10	15/20	15/20			15/20	mAMAX
		LM2940C	10	15		10	15
		VIN = VO + 5V, IO = 1A	30	45/60	50/60	30	45/60	50/60	mAMAX
	Output Noise	10 Hz − 100 kHz,	360		1000/ 1000	450		1000/1000	µVrms
	Voltage	IO = 5 mA
	Ripple Rejection	fO = 120 Hz, 1 Vrms,
		IO = 100 mA
		LM2940	66	54/48					dBMIN
		LM2940C	66	54		64	52
		fO = 1 kHz, 1 Vrms,			52/46			48/42	dBMIN
		IO = 5 mA

LM2940/LM2940C

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LM2940/LM2940C

Electrical Characteristics (Continued)

VIN = VO + 5V, IO = 1A, CO = 22 µF, unless otherwise specified. Boldface limits apply over the entire operating temperature range of the indicated device. All other specifications apply for TA = TJ = 25ÊC.

	Output Voltage (VO)			12V			15V
				LM2940	LM2940/833		LM2940	LM2940/833	Units
	Parameter	Conditions	Typ	Limit	Limit	Typ	Limit	Limit
				(Note 4)	(Note 5)		(Note 4)	(Note 5)
	Long Term		48			60			mV/
	Stability								1000 Hr
	Dropout Voltage	IO = 1A	0.5	0.8/1.0	0.7/1.0	0.5	0.8/1.0	0.7/1.0	VMAX
		IO = 100 mA	110	150/200	150/200	110	150/200	150/200	mVMAX
	Short Circuit	(Note 6)	1.9	1.6	1.6/1.3	1.9	1.6	1.6/1.3	AMIN
	Current
	Maximum Line	RO = 100Ω
	Transient	LM2940, T ≤ 100 ms	75	60/60
		LM2940/883, T ≤ 20 ms			40/40			40/40	VMIN
		LM2940C, T ≤ 1 ms	55	45		55	45
	Reverse Polarity	RO = 100Ω
	DC Input	LM2940, LM2940/883	−30	−15/ −15	−15/ −15			−15/ −15	VMIN
	Voltage	LM2940C	−30	−15		−30	−15
	Reverse Polarity	RO = 100Ω
	Transient Input	LM2940, T ≤ 100 ms	−75	−50/ −50
	Voltage	LM2940/883, T ≤ 20 ms			−45/ −45			−45/ −45	VMIN
		LM2940C, T ≤ 1 ms	−55	−45/ −45		−55	−45/ −45

Note 1: Absolute Maximum Ratings are limits beyond which damage to the device may occur. Operating Conditions are conditions under which the device functions but the specifications might not be guaranteed. For guaranteed specifications and test conditions see the Electrical Characteristics.

Note 2: The maximum allowable power dissipation is a function of the maximum junction temperature, TJ, the junction-to-ambient thermal resistance, θJ−A , and the ambient temperature, TA. Exceeding the maximum allowable power dissipation will cause excessive die temperature, and the regulator will go into thermal shutdown.

The value of θJ−A (for devices in still air with no heatsink) is 60ÊC/W for the TO-220 package, 80ÊC/W for the TO-263 package, and 174ÊC/W for the SOT-223 package. The effective value of θJ−A can be reduced by using a heatsink (see Application Hints for specific information on heatsinking). The values of θJ−A and θJ−C for the K02A

package are 39ÊC/W and 4ÊC/W respectively.

Note 3: ESD rating is based on the human body model, 100 pF discharged through 1.5 kΩ.

Note 4: All limits are guaranteed at TA = TJ = 25ÊC only (standard typeface) or over the entire operating temperature range of the indicated device (boldface type). All limits at TA = TJ = 25ÊC are 100% production tested. All limits at temperature extremes are guaranteed via correlation using standard Statistical Quality Control methods.

Note 5: All limits are guaranteed at TA = TJ = 25ÊC only (standard typeface) or over the entire operating temperature range of the indicated device (boldface type). All limits are 100% production tested and are used to calculate Outgoing Quality Levels.

Note 6: Output current will decrease with increasing temperature but will not drop below 1A at the maximum specified temperature.

Typical Performance Characteristics

Dropout Voltage	Dropout Voltage	Output Voltage
	vs Temperature	vs Temperature

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DS008822-14

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