TI LP2981A

SLVS521B − JULY 2004 − REVISED OCTOBER 2004
D Available in the Texas Instruments
D
D
D
D
D
D
D
D
D
D
NanoStar Chip Scale Package
Fixed/ADJ Versions
Output Tolerance of:
− 0.75% (A Grade)
− 1.25% (Standard Grade)
Ultra-Low Dropout, Typically
− 200 mV at Full Load of 100 mA
− 7 mV at 1 mA
Wide VIN Range . . . 16 V Max
Low IQ . . . 600 µA Typ at Full Load of
100 mA
Shutdown Current . . . 0.01 µA Typ
Fast Transient Response to Line and Load
Overcurrent and Thermal Protection
High Peak Current Capability
Portable Applications
− Mobile Phones
− Laptops
− Personal Digital Assistants (PDAs)
− Digital Cameras and Camcorders
− CD and MP3 Players
DBV (SOT-23) PACKAGE
(TOP VIEW)
VIN
GND
ON/OFF
1
5
VOUT
4
ADJ/NC†
2
3
YEQ, YEU, YZQ, OR YZU (WCSP) PACKAGE
(TOP VIEW)
GND
ADJ/NC†
VOUT
1 5
ON/OFF
2
3 4
VIN
† Must be left open in fixed-output versions
description/ordering information
The LP2981 family of fixed-output, low-dropout regulators offers exceptional, cost-effective performance for
both portable and nonportable applications. Available in adjustable version and in fixed voltages of 1.8 V,
2.5 V, 2.7 V, 2.8 V, 2.9 V, 3 V, 3.2 V, 3.3 V, 3.6 V, and 5 V, the family has an output tolerance of 0.75% for the
A-grade devices (1.25% for the standard grade) and is capable of delivering 100-mA continuous load current.
Standard regulator features, such as over-current and over-temperature protection, are included.
The LP2981 has features that make the regulator an ideal candidate for a variety of portable applications:
•
•
•
•
Low dropout: A PNP pass element allows a typical dropout of 200 mV at 100-mA load current and 7 mV
at 1-mA load.
Low quiescent current: The use of a vertical PNP process allows for quiescent currents that are
considerably lower than those associated with traditional lateral PNP regulators.
Shutdown: A shutdown feature is available, allowing the regulator to consume only 0.01 µA when the
ON/OFF pin is pulled low.
Small packaging: For the most space-constraint needs, the regulator is available in SOT-23 package
and NanoStar chip scale packaging. NanoStar package technology is a major breakthrough in IC
packaging concepts, using the die as the package.
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.
NanoStar is a trademark of Texas Instruments.
Copyright  2004, Texas Instruments Incorporated
!"# $"%&! '#(
'"! ! $#!! $# )# # #* "#
'' +,( '"! $!#- '# #!#&, !&"'#
#- && $##(
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description/ordering information (continued)
ORDERING INFORMATION
TJ
PART GRADE
VOUT
(NOM)
ADJ
1.25 V
1.8 V
2.5 V
2.7 V
2.8 V
−40°C to 125°C
A grade:
0.75% tolerance
ORDERABLE
PART NUMBER
PACKAGE†
SOT23-5 (DBV)
2.9 V
3V
3.2 V
3.3 V
3.6 V
5V
Reel of 3000
LP2981DBVR
Reel of 250
LP2981DBVT
Reel of 3000
LP2981A-125DBVR
Reel of 250
LP2981A-125DBVT
Reel of 3000
LP2981A-18DBVR
Reel of 250
LP2981A-18DBVT
Reel of 3000
LP2981A-25DBVR
Reel of 250
LP2981A-25DBVT
Reel of 3000
LP2981A-27DBVR
Reel of 250
LP2981A-27DBVT
Reel of 3000
LP2981A-28DBVR
Reel of 250
LP2981A-28DBVT
Reel of 3000
LP2981A-29DBVR
Reel of 250
LP2981A-29DBVT
Reel of 3000
LP2981A-30DBVR
Reel of 250
LP2981A-30DBVT
Reel of 3000
LP2981A-32DBVR
Reel of 250
LP2981A-32DBVT
Reel of 3000
LP2981A-33DBVR
Reel of 250
LP2981A-33DBVT
Reel of 3000
LP2981A-36DBVR
Reel of 250
LP2981A-36DBVT
Reel of 3000
LP2981A-50DBVR
Reel of 250
LP2981A-50DBVT
TOP-SIDE
MARKING‡
PREVIEW
PREVIEW
PREVIEW
PREVIEW
PREVIEW
LP6_
PREVIEW
LP8_
PREVIEW
LPC_
PREVIEW
PREVIEW
† Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are available at
www.ti.com/sc/package.
‡ DBV: The actual top-side marking has one additional character that designates the assembly/test site.
2
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SLVS521B − JULY 2004 − REVISED OCTOBER 2004
ORDERING INFORMATION (continued)
TJ
PART GRADE
VOUT
(NOM)
ORDERABLE
PART NUMBER
PACKAGE†
ADJ
LP2981YEQR
1.25 V
LP2981A-125YEQR
1.8 V
LP2981A-18YEQR
2.5 V
LP2981A-25YEQR
2.7 V
2.8 V
−40°C to 125°C
A grade:
0.75% tolerance
LP2981A-27YEQR
NanoStar − WCSP
0.17-mm Bump (YEQ)
Reel of 3000
LP2981A-28YEQR
2.9 V
LP2981A-29YEQR
3V
LP2981A-30YEQR
3.2 V
LP2981A-32YEQR
3.3 V
LP2981A-33YEQR
5V
LP2981A-50YEQR
ADJ
LP2981YZQR
1.25 V
LP2981A-125YZQR
1.8 V
LP2981A-18YZQR
2.5 V
LP2981A-25YZQR
2.7 V
2.8 V
2.9 V
TOP-SIDE
MARKING‡
NanoFree − WCSP
0.17-mm Bump
(YZQ, Pb-free)
LP2981A-27YZQR
Reel of 3000
LP2981A-28YZQR
LP2981A-29YZQR
3V
LP2981A-30YZQR
3.2 V
LP2981A-32YZQR
3.3 V
LP2981A-33YZQR
5V
LP2981A-50YZQR
† Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are available at
www.ti.com/sc/package.
‡ YEQ/YZQ: The actual top-side marking has three preceding characters to denote year, month, and sequence code, and one following character
to designate the assembly/test site. Pin 1 identifier indicates solder-bump composition (1 = SnPb, • = Pb-free).
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SLVS521B − JULY 2004 − REVISED OCTOBER 2004
ORDERING INFORMATION (continued)
TJ
PART GRADE
VOUT
(NOM)
ORDERABLE
PART NUMBER
PACKAGE†
ADJ
LP2981YEUR
1.25 V
LP2981A-125YEUR
1.8 V
LP2981A-18YEUR
2.5 V
LP2981A-25YEUR
2.7 V
2.8 V
−40°C to 125°C
A grade:
0.75% tolerance
LP2981A-27YEUR
NanoStar − WCSP
0.30-mm Bump (YEU)
Reel of 3000
LP2981A-28YEUR
2.9 V
LP2981A-29YEUR
3V
LP2981A-30YEUR
3.2 V
LP2981A-32YEUR
3.3 V
LP2981A-33YEUR
5V
LP2981A-50YEUR
ADJ
LP2981YZUR
1.25 V
LP2981A-125YZUR
1.8 V
LP2981A-18YZUR
2.5 V
LP2981A-25YZUR
2.7 V
2.8 V
2.9 V
TOP-SIDE
MARKING‡
NanoFree − WCSP
0.30-mm Bump
(YZU, Pb-free)
LP2981A-27YZUR
Reel of 3000
LP2981A-28YZUR
LP2981A-29YZUR
3V
LP2981A-30YZUR
3.2 V
LP2981A-32YZUR
3.3 V
LP2981A-33YZUR
5V
LP2981A-50YZUR
† Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are available at
www.ti.com/sc/package.
‡ YEU/YZU: The actual top-side marking has three preceding characters to denote year, month, and sequence code, and one following character
to designate the assembly/test site. Pin 1 identifier indicates solder-bump composition (1 = SnPb, • = Pb-free).
4
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SLVS521B − JULY 2004 − REVISED OCTOBER 2004
ORDERING INFORMATION (continued)
TJ
PART GRADE
VOUT
(NOM)
ADJ
1.25 V
1.8 V
2.5 V
2.7 V
2.8 V
−40°C to 125°C
Standard grade:
1.25% tolerance
ORDERABLE
PART NUMBER
PACKAGE†
SOT-23 (DBV)
2.9 V
3V
3.2 V
3.3 V
3.6 V
5V
Reel of 3000
LP2981DBVR
Reel of 250
LP2981DBVT
Reel of 3000
LP2981-125DBVR
Reel of 250
LP2981-125DBVT
Reel of 3000
LP2981-18DBVR
Reel of 250
LP2981-18DBVT
Reel of 3000
LP2981-25DBVR
Reel of 250
LP2981-25DBVT
Reel of 3000
LP2981-27DBVR
Reel of 250
LP2981-27DBVT
Reel of 3000
LP2981-28DBVR
Reel of 250
LP2981-28DBVT
Reel of 3000
LP2981-29DBVR
Reel of 250
LP2981-29DBVT
Reel of 3000
LP2981-30DBVR
Reel of 250
LP2981-30DBVT
Reel of 3000
LP2981-32DBVR
Reel of 250
LP2981-32DBVT
Reel of 3000
LP2981-33DBVR
Reel of 250
LP2981-33DBVT
Reel of 3000
LP2981-36DBVR
Reel of 250
LP2981-36DBVT
Reel of 3000
LP2981-50DBVR
Reel of 250
LP2981-50DBVT
TOP-SIDE
MARKING‡
PREVIEW
PREVIEW
PREVIEW
PREVIEW
PREVIEW
LP5_
PREVIEW
LP7_
PREVIEW
LPB_
PREVIEW
PREVIEW
† Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are available at
www.ti.com/sc/package.
‡ DBV: The actual top-side marking has one additional character that designates the assembly/test site.
POST OFFICE BOX 655303
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5
SLVS521B − JULY 2004 − REVISED OCTOBER 2004
ORDERING INFORMATION (continued)
TJ
PART GRADE
VOUT
(NOM)
ORDERABLE
PART NUMBER
PACKAGE†
ADJ
LP2981YEQR
1.25 V
LP2981−125YEQR
1.8 V
LP2981−18YEQR
2.5 V
LP2981-25YEQR
2.7 V
2.8 V
−40°C to 125°C
Standard grade:
1.25% tolerance
LP2981-27YEQR
NanoStar − WCSP
0.17-mm Bump (YEQ)
Reel of 3000
LP2981-28YEQR
2.8 V
LP2981-29YEQR
3V
LP2981-30YEQR
3.2 V
LP2981-32YEQR
3.3 V
LP2981-33YEQR
5V
LP2981-50YEQR
ADJ
LP2981YZQR
1.25 V
LP2981−125YZQR
1.8 V
LP2981−18YZQR
2.5 V
LP2981-25YZQR
2.7 V
2.8 V
2.8 V
TOP-SIDE
MARKING‡
NanoFree − WCSP
0.17-mm Bump
(YZQ, Pb-free)
LP2981-27YZQR
Reel of 3000
LP2981-28YZQR
LP2981-29YZQR
3V
LP2981-30YZQR
3.2 V
LP2981-32YZQR
3.3 V
LP2981-33YZQR
5V
LP2981-50YZQR
† Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are available at
www.ti.com/sc/package.
‡ YEQ/YZQ: The actual top-side marking has three preceding characters to denote year, month, and sequence code, and one following character
to designate the assembly/test site. Pin 1 identifier indicates solder-bump composition (1 = SnPb, • = Pb-free).
6
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SLVS521B − JULY 2004 − REVISED OCTOBER 2004
ORDERING INFORMATION (continued)
TJ
PART GRADE
VOUT
(NOM)
ORDERABLE
PART NUMBER
PACKAGE†
ADJ
LP2981YEUR
1.25 V
LP2981−125YEUR
1.8 V
LP2981−18YEUR
2.5 V
LP2981-25YEUR
2.7 V
2.8 V
−40°C to 125°C
Standard grade:
1.25% tolerance
LP2981-27YEUR
NanoStar − WCSP
0.30-mm Bump (YEU)
Reel of 3000
LP2981-28YEUR
2.8 V
LP2981-29YEUR
3V
LP2981-30YEUR
3.2 V
LP2981-32YEUR
3.3 V
LP2981-33YEUR
5V
LP2981-50YEUR
ADJ
LP2981YZUR
1.25 V
LP2981−125YZUR
1.8 V
LP2981−18YZUR
2.5 V
LP2981-25YZUR
2.7 V
2.8 V
2.8 V
TOP-SIDE
MARKING‡
NanoFree − WCSP
0.30-mm Bump
(YZU, Pb-free)
LP2981-27YZUR
Reel of 3000
LP2981-28YZUR
LP2981-29YZUR
3V
LP2981-30YZUR
3.2 V
LP2981-32YZUR
3.3 V
LP2981-33YZUR
5V
LP2981-50YZUR
† Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are available at
www.ti.com/sc/package.
‡ YEU/YZU: The actual top-side marking has three preceding characters to denote year, month, and sequence code, and one following character
to designate the assembly/test site. Pin 1 identifier indicates solder-bump composition (1 = SnPb, • = Pb-free).
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7
SLVS521B − JULY 2004 − REVISED OCTOBER 2004
functional block diagram
VIN
ON/OFF
VREF
1.23 V
−
+
ADJ/NC†
R1
VOUT
Overcurrent/
Overtemperature
Protection
R2
GND
† Fixed versions: Must be left open
ADJ versions: R1 = ∞, R2 = ∞
Figure 1
basic application circuit
LP2981A-xxDBVR (Fixed Version)
VIN
1
VOUT
5
3.3 µF†
1 µF†
GND
2
ON/OFF‡
3
4
NC§
† Minimum Cout value for stability (can be increased without limit for improved stability and transient response)
‡ ON/OFF must be actively terminated. Connect to VIN if shutdown feature is not used.
§ Must be left open
Figure 2
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SLVS521B − JULY 2004 − REVISED OCTOBER 2004
basic application circuit (continued)
LP2981-xxDBVR (Adjustable Version)
VIN
1
ǒ
R
VOUT = VREF 1 ) ADJ
R1
5
Ǔ
3.3 µF†
1 µF†
GND
2
ON/OFF‡
3
RADJ
4
ADJ
R1 3 39.5 kW‡
† Minimum Cout value for stability (can be increased without limit for improved stability and transient response)
‡ See Application Information
Figure 3
absolute maximum ratings over the virtual junction temperature range (unless otherwise noted)†
Continuous input voltage range, VIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.3 V to 16 V
ON/OFF input voltage range, VON/OFF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.3 V to 16 V
Output voltage range (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.3 V to 9 V
Input/output voltage differential range, VIN-VOUT (see Note 2) . . . . . . . . . . . . . . . . . . . . . . . . . . −0.3 V to 16 V
Output current, IOUT (see Note 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Internally limited (short-circuit protected)
Package thermal impedance, θJA (see Notes 3 and 4): DBV package . . . . . . . . . . . . . . . . . . . . . . . . 206°C/W
YEQ/YZQ package . . . . . . . . . . . . . . . . . . TBD°C/W
YEU/YZU package . . . . . . . . . . . . . . . . . . . TBD°C/W
Operating virtual junction temperature, TJ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150°C
Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −65°C to 150°C
† Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTES: 1. If load is returned to a negative power supply, the output must be diode clamped to GND.
2. The PNP pass transistor has a parasitic diode connected between the input and output. This diode normally is reverse biased
(VIN > VOUT), but will be forward biased if the output voltage exceeds the input voltage by a diode drop (see Application Information
for more details).
3. Maximum power dissipation is a function of TJ(max), qJA, and TA. The maximum allowable power dissipation at any allowable
ambient temperature is PD = (TJ(max) − TA)/qJA. Operating at the absolute maximum TJ of 150°C can affect reliability.
4. The package thermal impedance is calculated in accordance with JESD 51-7.
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SLVS521B − JULY 2004 − REVISED OCTOBER 2004
recommended operating conditions
MIN
VIN
VON/OFF
Supply input voltage
VIN-VOUT
IOUT
Input-output differential
ON/OFF input voltage
MAX
16
V
0
VIN
11
V
100
mA
125
°C
0.7
Output current
Virtual junction temperature
TJ
† Minimum VIN of 2.2 V is needed for proper biasing of LDO control circuitry.
UNIT
2.2†
−40
V
electrical characteristics at specified free-air temperature range, VIN = VOUT(NOM) + 1 V,
VON/OFF = 2 V, CIN = 1 mF, IL = 1 mA, COUT = 4.7 mF, ADJ version: ADJ connected to VOUT (unless
otherwise noted)
LP2981A-XX
PARAMETER
nVOUT
nVOUT/nVIN
TEST CONDITIONS
Output voltage IL = 1 mA
tolerance
IL = 1 mA to 100 mA
(see Note 5)
Output voltage VIN =
line regulation [VOUT(NOM) + 1 V] to 16 V
TA
MIN
25°C
−0.75
25°C
−40°C to 125°C
IL = 1 mA
−40°C to 125°C
−2
2
−3.5
3.5
0.007
1
7
70
−40°C to 125°C
80
IGND
200
−40°C to 125°C
600
−40°C to 125°C
VON/OFF < 0.3 V (OFF)
VON/OFF < 0.15 V (OFF)
ON/OFF input
voltage
(see Note 7)
High = O/P ON
200
250
375
95
65
95
125
110
80
110
170
300
200
300
550
800
600
1500
0.01
0.8
0.01
0.8
0.05
2
0.05
2
−40°C to 125°C
5
5
1.4
1.4
1.6
−40°C to 125°C
µA
800
25°C
−40°C to 125°C
mV
150
250
−40°C to 105°C
25°C
Low = O/P OFF
100
1500
25°C
VON/OFF
70
15
100
550
25°C
IL = 100 mA
10
170
25°C
IL = 25 mA
3
7
125
25°C
Ground pin
current
10
375
65
%/V
5
150
200
25°C
IL = 1 mA
1
15
−40°C to 125°C
−40°C to 125°C
3
%VNOM
0.014
0.032
5
25°C
IL = 0
0.007
0.032
−40°C to 125°C
IL = 100 mA
0.014
UNIT
1.25
1
25°C
IL = 25 mA
MAX
2.5
25°C
VIN-VOUT
TYP
0.75 −1.25
−40°C to 125°C
−40°C to 125°C
MIN
−1
25°C
IL = 0
MAX
−2.5
25°C
Dropout
voltage
(see Note 6)
TYP
LP2981-XX
1.6
0.5
V
0.5
0.15
0.15
NOTES: 5. VOUT = VREF for ADJ version
6. Dropout voltage is defined as the input-to-output differential at which the output voltage drops 100 mV below the value measured
with a 1-V differential. This dropout specification does not apply to the 1.8-V option, as the minimum VIN = 2.2 V must be observed
for proper biasing of LDO control circuitry.
7. The ON/OFF input must be actively terminated. Connect to VIN if this function is not used (see Application Information).
10
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electrical characteristics at specified free-air temperature range, VIN = VOUT(NOM) + 1 V,
VON/OFF = 2 V, CIN = 1 mF, IL = 1 mA, COUT = 4.7 mF, ADJ version: ADJ connected to VOUT (unless
otherwise noted) (continued)
LP2981A-XX
PARAMETER
TEST CONDITIONS
TA
MIN
25°C
ION/OFF
ON/OFF input
current
VON/OFF = 0
TYP
VOUT≥VOUT(NOM) − 5%
25°C
Vn
Output noise
voltage (RMS)
BW = 300 Hz to 50 kHz,
COUT = 10 µF
25°C
nVOUT/nVIN
Ripple
rejection
f = 1kHz, COUT = 10 µF
IOUT(MAX)
Short-circuit
current
RL = 0 (steady state)
TYP
−1
5
15
A
µA
15
mA
160
160
µV
25°C
63
63
dB
25°C
150
150
mA
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400
UNIT
400
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150
MAX
0.01
5
−40°C to 125°C
Peak output
current
MIN
−1
25°C
IOUT(PK)
MAX
0.01
−40°C to 125°C
VON/OFF = 5 V
LP2981-XX
150
11
SLVS521B − JULY 2004 − REVISED OCTOBER 2004
APPLICATION INFORMATION
capacitors
input capacitor (Cin)
A minimum value of 1 mF (over the entire operating temperature range) is required at the input of the LP2981.
In addition, this input capacitor should be located within 1 cm of the input pin and connected to a clean analog
ground. There is no Equivalent Series Resistance (ESR) requirement for this capacitor, and the capacitance
can be increased without limit. A good quality ceramic or tantalum capacitor can be used.
output capacitor (Cout)
As a PNP regulator, the LP2981 requires the output capacitor to meet both a minimum capacitance and ESR
value. Required ESR values as a function of load current are provided for various output voltages, load currents,
and capacitances (see Figures 1–4).
Minimum Cout: 3.3 µF (can be increased without limit to improve transient response stability margin)
ESR − Ω
ESR − Ω
ESR range: see Figures 1–4
Load Current − mA
Figure 5. 5-V/10-µF ESR Curves
ESR − Ω
ESR − Ω
Figure 4. 5-V/3.3-µF ESR Curves
Load Current − mA
Load Current − mA
Figure 6. 3-V/3.3-µF ESR Curves
12
POST OFFICE BOX 655303
Load Current − mA
Figure 7. 3-V/10-µF ESR Curves
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SLVS521B − JULY 2004 − REVISED OCTOBER 2004
APPLICATION INFORMATION
output capacitor (Cout) (continued)
It is critical that both the minimum capacitance and ESR requirement be met over the entire operating
temperature range. Depending on the type of capacitor used, both of these parameters can vary significantly
with temperature (see capacitor characteristics section).
capacitor characteristics
ceramics
Due to their very low ESR values, ceramic capacitors are not suitable for use as the output capacitor. For
instance, a typical 2.2-µF ceramic capacitor has an ESR in the range of 10 mΩ to 20 mΩ and, thus, easily can
fall out of minimum ESR requirements under certain operating conditions.
If a ceramic capacitor is used at the output, a 1-Ω resistor should be placed in series with the capacitor to raise
the ESR seen by the regulator.
tantalum
Solid tantalum capacitors are optimal choices for the LP2981, but they still must meet the minimum ESR
requirement. Note that the ESR of a tantalum capacitor increases as temperature drops, as much as double
from 25°C to −40°C. Thus, ESR margins must be maintained over the temperature range to prevent regulator
instability. For operation at very low temperatures, paralleling a tantalum capacitor with a ceramic one keeps
the combined ESR from increasing near the upper limit of the ESR curve.
aluminum
Aluminum capacitors can be used, but use with the LP2981 is impractical due to their large physical dimensions.
They also must meet the ESR requirements over the full temperature range. In this regard, aluminium capacitors
are at a big disadvantage due to their sharp ESR increase as temperature drops. For example, over a
temperature drop from 20°C to −40°C, the ESR of an aluminum electrolytic capacitor can increase by a factor
of 50. In addition, some of the electrolytes used in these capacitors can freeze at −25°C, making the capacitor
nonoperational.
ON/OFF operation
The LP2981 allows for a shutdown mode via the ON/OFF pin. If the shutdown feature is not used, ON/OFF
should be connected to the input to ensure that the regulator is on at all times. To drive ON/OFF:
•
•
•
A LOW (≤0.3 V) turns the regulator OFF; a HIGH (≥1.6 V) turns it ON.
Use either a totem-pole output or an open-collector output with a pullup resistor tied to VIN (or another
logic supply). The HIGH signal can exceed VIN, but must not exceed the absolute maximum ratings of
20 V for the ON/OFF pin.
Apply a signal with a slew rate of ≥40 mV/µs. A slow slew rate can cause the shutdown function to
operate incorrectly.
ADJ version
From Figure 3, VOUT is set according to the following equation:
ǒ
VOUT = VREF 1 )
R ADJ
R1
Ǔ
where VREF = 1.23 V (nominal). Under no-load conditions, a minimum “bias” current is required through the RADJ
and R1 divider to maintain regulator stability. Therefore, the maximum value for R1 should be X39.5 kΩ.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
13
SLVS521B − JULY 2004 − REVISED OCTOBER 2004
APPLICATION INFORMATION
reverse input-output voltage
An inherent diode is present across the PNP pass element of the LP2981.
VIN
VOUT
With the anode connected to the output, this diode is reverse biased during normal operation, since the input
voltage is higher than the output. However, if the output is pulled one VBE higher than the input, or if the input
is abruptly stepped below the output, this diode is forward biased and can cause a parasitic silicon-controlled
rectifier (SCR) to latch, resulting in current flowing from the output to the input (values in excess of 100 mA can
cause damage). Thus, to prevent possible damage to the regulator in any application where the output may be
pulled above the input, an external Schottky diode must be connected between the output and input. With the
anode on output, this Schottky limits the reverse voltage across the output and input pins to 0.3 V, preventing
the regulator’s internal diode from forward biasing.
Schottky
VIN
VOUT
LP2981
pin 4: NC
Pin 4 must be left OPEN. Do not connect anything to this pin, as it is used for post package trim.
14
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SLVS521B − JULY 2004 − REVISED OCTOBER 2004
WAFER CHIP SCALE INFORMATION
LP2981x-xxYEQ NanoStar (0.17-mm Bump)
LP2981x-xxYZQ NanoFree (0.17-mm Pb-Free Bump)
987
1,037
1,287
1,337
Pin A1 Index Area
0,19
0,15
0,625 Max
0,15
0,10
NOTES: A.
B.
C.
D.
All linear dimensions are in millimeters.
This drawing is subject to change without notice.
NanoStar package configuration.
This package is tin-lead (SnPb); consult the factory for availability of lead-free material.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
15
SLVS521B − JULY 2004 − REVISED OCTOBER 2004
WAFER CHIP SCALE INFORMATION
LP2981x-xxYEU NanoStar (0.30-mm Bump)
LP2981x-xxYZU NanoFree (0.30-mm Pb-Free Bump)
987
1,037
1,287
1,337
Pin A1 Index Area
0,75 Max
0,30
0,20
NOTES: A.
B.
C.
D.
16
All linear dimensions are in millimeters.
This drawing is subject to change without notice.
NanoStar package configuration.
This package is tin-lead (SnPb); consult the factory for availability of lead-free material.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
0,35
0,25
PACKAGE OPTION ADDENDUM
www.ti.com
24-Jun-2005
PACKAGING INFORMATION
(1)
Orderable Device
Status (1)
Package
Type
Package
Drawing
Pins Package Eco Plan (2)
Qty
LP2981-28DBVR
ACTIVE
SOT-23
DBV
5
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981-28DBVRE4
ACTIVE
SOT-23
DBV
5
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981-28DBVT
ACTIVE
SOT-23
DBV
5
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981-28DBVTE4
ACTIVE
SOT-23
DBV
5
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981-30DBVR
ACTIVE
SOT-23
DBV
5
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981-30DBVRE4
ACTIVE
SOT-23
DBV
5
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981-30DBVT
ACTIVE
SOT-23
DBV
5
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981-30DBVTE4
ACTIVE
SOT-23
DBV
5
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981-33DBVR
ACTIVE
SOT-23
DBV
5
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981-33DBVRE4
ACTIVE
SOT-23
DBV
5
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981-33DBVT
ACTIVE
SOT-23
DBV
5
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981-33DBVTE4
ACTIVE
SOT-23
DBV
5
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981A-28DBVR
ACTIVE
SOT-23
DBV
5
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981A-28DBVRE4
ACTIVE
SOT-23
DBV
5
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981A-28DBVT
ACTIVE
SOT-23
DBV
5
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981A-28DBVTE4
ACTIVE
SOT-23
DBV
5
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981A-30DBVR
ACTIVE
SOT-23
DBV
5
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981A-30DBVRE4
ACTIVE
SOT-23
DBV
5
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981A-30DBVT
ACTIVE
SOT-23
DBV
5
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981A-30DBVTE4
ACTIVE
SOT-23
DBV
5
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981A-33DBVR
ACTIVE
SOT-23
DBV
5
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981A-33DBVRE4
ACTIVE
SOT-23
DBV
5
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981A-33DBVT
ACTIVE
SOT-23
DBV
5
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
LP2981A-33DBVTE4
ACTIVE
SOT-23
DBV
5
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
The marketing status values are defined as follows:
Addendum-Page 1
Lead/Ball Finish
MSL Peak Temp (3)
PACKAGE OPTION ADDENDUM
www.ti.com
24-Jun-2005
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)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS) 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.
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.
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Addendum-Page 2
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