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LP2980-N
SNOS733P – APRIL 2000 – REVISED SEPTEMBER 2016
LP2980-N Micropower 50-mA Ultra-Low-Dropout Regulator in SOT-23 Package
1 Features
3 Description
•
•
•
•
•
•
•
•
•
•
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The LP2980-N is a 50-mA, fixed-output voltage
regulator designed specifically to meet the
requirements of battery-powered applications.
1
2.1-V to 16-V Input Voltage Range
5-V, 4.7-V, 3.3-V, 3-V, and 2.5-V Output Versions
Ultra-Low-Dropout Voltage
Output Voltage Accuracy 0.5% (A Grade)
Ensured 50-mA Output Current
Requires Only 1-μF External Capacitance
< 1-μA Quiescent Current When Shutdown
Low Ground Pin Current at All Load Currents
High Peak Current Capability (150 mA Typical)
Wide Supply Voltage Range (16 V Maximum)
Fast Dynamic Response to Line and Load
Low ZOUT Over Wide Frequency Range
Overtemperature and Overcurrent Protection
−40°C to 125°C Junction Temperature Range
Using an optimized VIP (Vertically Integrated PNP)
process,
the
LP2980-N
delivers
unequaled
performance in all specifications critical to batterypowered designs:
Dropout voltage: Typically 120 mV at 50-mA load,
and 7 mV at 1-mA load.
Ground pin current: Typically 375 μA at 50-mA load,
and 80 μA at 1-mA load.
Sleep mode: Less than 1-μA quiescent current when
ON/OFF pin is pulled to less than 0.18 V.
Minimum part count: Requires only a 1-μF capacitor
on the regulator output.
Precision output: Initial output voltage tolerance of
±0.5% (A grade).
2 Applications
•
•
•
•
Cellular Phone
Palmtop/Laptop Computer
Personal Digital Assistant (PDA)
Camcorder, Personal Stereo, Camera
5-V, 4.7-V, 3.3-V, 3-V, and 2.5-V versions available
as standard products.
Device Information(1)
PART NUMBER
LP2980-N
PACKAGE
BODY SIZE (NOM)
SOT-23 (5)
2.90 mm × 1.60 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Simplified Schematic
VIN
IN
CIN
1 µF
VOUT
OUT
COUT
2.2 µF
LP2980
GND
ON/OFF
ON/OFF
NC
Copyright © 2016, Texas Instruments Incorporated
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
LP2980-N
SNOS733P – APRIL 2000 – REVISED SEPTEMBER 2016
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Table of Contents
1
2
3
4
5
6
7
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Pin Configuration and Functions .........................
Specifications.........................................................
1
1
1
2
3
4
6.1
6.2
6.3
6.4
6.5
6.6
4
4
4
4
5
7
Absolute Maximum Ratings ......................................
ESD Ratings..............................................................
Recommended Operating Conditions.......................
Thermal Information ..................................................
Electrical Characteristics...........................................
Typical Characteristics ..............................................
Detailed Description ............................................ 12
7.1 Overview ................................................................. 12
7.2 Functional Block Diagram ....................................... 12
7.3 Feature Description................................................. 12
7.4 Device Functional Modes........................................ 13
8
Application and Implementation ........................ 14
8.1 Application Information............................................ 14
8.2 Typical Application ................................................. 14
9 Power Supply Recommendations...................... 22
10 Layout................................................................... 22
10.1 Layout Guidelines ................................................. 22
10.2 Layout Example .................................................... 22
11 Device and Documentation Support ................. 23
11.1
11.2
11.3
11.4
11.5
11.6
Device Support......................................................
Receiving Notification of Documentation Updates
Community Resources..........................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
23
23
23
23
23
23
12 Mechanical, Packaging, and Orderable
Information ........................................................... 23
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision O (June 2015) to Revision P
Page
•
Changed minor wording in Description for clarity................................................................................................................... 1
•
Deleted input supply voltage (operating) row; deleted "(survival)" from rows of Abs Max table ........................................... 4
•
Deleted lead temperature from Abs Max per new format rules.............................................................................................. 4
•
Added "(operating") from ROC table; add second row for "Shutdown input voltage" to ROC ............................................... 4
•
Added "High K" and footnote 2 to Thermal Information ........................................................................................................ 4
•
Changed "...an output tolerance of %..." to "...an initial output voltage tolerance of ±0.5%..." ........................................... 12
•
Deleted "Very high accuracy 1.23-V reference" .................................................................................................................. 12
•
Changed "150 mA" to "50 mA" to correct typo from reformat (2 places) ............................................................................. 12
•
Changed "...only 1 µA" to "...less than 1 µA"........................................................................................................................ 12
•
Changed "... pulled low" to "...pulled to less than 0.18 V" ................................................................................................... 12
Changes from Revision N (December 2014) to Revision O
Page
•
Changed pin names VOUT to OUT and VIN to IN per TI nomenclature; correct typos ....................................................... 1
•
Changed format of ESD Ratings table .................................................................................................................................. 4
•
Deleted (the TO-220 package alone will safely dissipate this) - no TO-220 package for this part ...................................... 20
Changes from Revision M (April 2013) to Revision N
•
2
Page
Added Pin Configuration and Functions section, ESD Ratings table, Feature Description section, Device Functional
Modes, Application and Implementation section, Power Supply Recommendations section, Layout section, Device
and Documentation Support section, and Mechanical, Packaging, and Orderable Information section; add updated
Thermal Information .............................................................................................................................................................. 1
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Changes from Revision L (April 2013) to Revision M
•
Page
Changed layout of National Semiconductor data sheet to TI format.................................................................................... 22
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5 Pin Configuration and Functions
DBV Package
5 Pin SOT-23
Top View
Pin Functions
PIN
NO.
NAME
I/O
1
IN
I
2
GND
—
3
ON/OFF
I
DESCRIPTION
Input voltage
Common ground (device substrate)
Logic high enable input
4
N/C
—
DO NOT CONNECT. Device pin 4 is reserved for post packaging test and calibration of the
LP2980-N VOUT accuracy. Device pin 4 must be left floating. Do not connect to any potential.
Do not connect to ground. Any attempt to do pin continuity testing on device pin 4 is
discouraged. Continuity test results will be variable depending on the actions of the factory
calibration. Aggressive pin continuity testing (high voltage, or high current) on device pin 4
may activate the trim circuitry forcing VOUT to move out of tolerance.
5
OUT
O
Regulated output voltage
4
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6 Specifications
6.1 Absolute Maximum Ratings (1) (2)
MIN
MAX
UNIT
Operating junction temperature
−40
125
°C
Power dissipation (3)
Internally Limited
Input supply voltage
−0.3
16
V
Shutdown input voltage
−0.3
16
V
Output voltage (4)
−0.3
9
V
IOUT
Short-circuit protected
Input-output voltage (5)
−0.3
16
V
Storage temperature, Tstg
–65
150
°C
(1)
(2)
(3)
(4)
(5)
Absolute Maximum Ratings indicate limits beyond which damage to the component may occur. Electrical specifications do not apply
when operating the device outside of its rated operating conditions.
If Military/Aerospace-specified devices are required, contact the Texas Instruments Sales Office/Distributors for availability and
specifications.
The maximum allowable power dissipation is a function of the maximum junction temperature, TJ(MAX), the junction-to-ambient thermal
resistance, RθJA, and the ambient temperature, TA. The maximum allowable power dissipation at any ambient temperature is calculated
using P(MAX) = ( (TJ(MAX) – TA) / RθJA).
The value of RθJA for the SOT-23 package is 175.7°C/W. Exceeding the maximum allowable power dissipation will cause excessive die
temperature, and the regulator will go into thermal shutdown.
If used in a dual-supply system where the regulator load is returned to a negative supply, the LP2980-N output must be diode-clamped
to ground.
The output PNP structure contains a diode between the IN and OUT pins that is normally reverse-biased. Reversing the polarity from
VIN to VOUT turns on this diode (see Reverse Current Path).
6.2 ESD Ratings
VALUE
V(ESD)
(1)
Electrostatic
discharge
Human-body model (HBM), per
ANSI/ESDA/JEDEC JS-001 (1)
All pins except 3 and 4
±2000
Pins 3 and 4
±1000
UNIT
V
JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
6.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
Operating junction temperature
Input supply voltage
Shutdown input voltage
MIN
MAX
UNIT
−40
125
°C
2.1
16
0
VIN
V
6.4 Thermal Information
LP2980-N
THERMAL METRIC
(1)
DBV
UNIT
5 PINS
RθJA
Junction-to-ambient thermal resistance, High K (2)
RθJC(top)
Junction-to-case (top) thermal resistance
RθJB
Junction-to-board thermal resistance
ψJT
Junction-to-top characterization parameter
2.8
°C/W
ψJB
Junction-to-board characterization parameter
30.3
°C/W
(1)
(2)
175.7
°C/W
78
°C/W
30.8
°C/W
For more information about traditional and new thermal metrics, see Semiconductor and IC Package Thermal Metrics.
Thermal resistance value RθJA is based on the EIA/JEDEC High-K printed circuit board defined by JESD51-7 - High Effective Thermal
Conductivity Test Board for Leaded Surface Mount Packages.
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6.5 Electrical Characteristics
Unless otherwise specified: TJ = 25°C, VIN = VO(NOM) + 1 V, IL = 1 mA, COUT = 1 μF, VON/OFF = 2 V. (1)
PARAMETER
TEST CONDITIONS
Output voltage tolerance
Output voltage line
regulation
VIN – VO
IGND
Dropout voltage (3)
Ground pin current
MIN
TYP
VON/OFF
ON/OFF input voltage
MAX
MIN
TYP
MAX
−0.5
0.5
−1
1
−0.75
0.75
−1.5
1.5
1 mA < IL < 50 mA
–40°C ≤ TJ ≤ 125°C
−2.5
2.5
−3.5
3.5
VO(NOM) + 1 V ≤ VIN ≤ 16 V
0.007
0.014
0.007
0.014
VO(NOM) + 1 V ≤ VIN ≤ 16 V
–40°C ≤ TJ ≤ 125°C
0.007
0.032
0.007
0.032
IL = 0 mA
1
3
1
3
IL = 0 mA, –40°C ≤ TJ ≤
125°C
1
5
1
5
IL = 1 mA
7
10
7
10
IL = 1 mA, –40°C ≤ TJ ≤
125°C
7
15
7
15
IL = 10 mA
40
60
40
60
IL = 10 mA, –40°C ≤ TJ ≤
125°C
40
90
40
90
IL = 50 mA
120
150
120
150
IL = 50 mA, –40°C ≤ TJ ≤
125°C
120
225
120
225
IL = 0 mA
65
95
65
95
IL = 0 mA, –40°C ≤ TJ ≤
125°C
65
125
65
125
IL = 1 mA
80
110
80
110
IL = 1 mA, –40°C ≤ TJ ≤
125°C
80
170
80
170
IL = 10 mA
140
220
140
220
IL = 10 mA, –40°C ≤ TJ ≤
125°C
140
460
140
460
IL = 50 mA
375
600
375
600
IL = 50 mA, –40°C ≤ TJ ≤
125°C
375
1200
375
1200
0
1
0
1
VON/OFF < 0.18 V
–40°C ≤ TJ ≤ 125°C
(4)
LP2980I-XX (2)
1 mA < IL < 50 mA
IL = 1 mA
ΔVO
LP2980AI-XX (2)
High = O/P ON
–40°C ≤ TJ ≤ 125°C
1.6
1.4
1.6
0.55
0.18
0.55
0.18
VON/OFF = 0 V
0
−1
0
−1
VON/OFF = 5 V
–40°C ≤ TJ ≤ 125°C
5
15
5
15
IO(PK)
Peak output current
VOUT ≥ VO(NOM) − 5%
en
Output noise voltage
(RMS)
BW = 300 Hz to 50 kHz
COUT = 10 μF
ΔVOUT /
ΔVIN
Ripple rejection
f = 1 kHz
COUT = 10 μF
(3)
(4)
6
%/V
mV
μA
V
Low = O/P OFF
–40°C ≤ TJ ≤ 125°C
ON/OFF input current
(2)
%VNOM
1.4
ION/OFF
(1)
UNIT
100
150
100
μA
150
mA
160
160
μV
63
63
dB
Minimum and maximum limits are ensured through test, design, or statistical correlation over the junction temperature (TJ) range of
–40°C to +125°C, unless otherwise stated. Typical values represent the most likely parametric norm at TA = 25°C, and are provided for
reference purposes only.
Limits are 100% production tested at 25°C. Limits over the operating temperature range are ensured through correlation using statistical
quality control (SQC) methods. The limits are used to calculate average outgoing quality level (AOQL).
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.
The ON/OFF inputs must be properly driven to prevent misoperation. For details, see ON/OFF Input Operation.
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Electrical Characteristics (continued)
Unless otherwise specified: TJ = 25°C, VIN = VO(NOM) + 1 V, IL = 1 mA, COUT = 1 μF, VON/OFF = 2 V.(1)
PARAMETER
IO(MAX)
(5)
Short-circuit current
TEST CONDITIONS
LP2980AI-XX (2)
MIN
TYP
RL = 0 Ω (steady state) (5)
150
LP2980I-XX (2)
MAX
MIN
TYP
MAX
150
UNIT
mA
See related curve(s) in Typical Characteristics section.
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6.6 Typical Characteristics
Unless otherwise specified: TA = 25°C, VIN = VO(NOM) + 1 V, COUT = 2.2 μF, all voltage options, ON/OFF pin tied to VIN.
Figure 1. Output Voltage vs Temperature
Figure 2. Output Voltage vs Temperature
Figure 3. Output Voltage vs Temperature
Figure 4. Dropout Characteristics
Figure 5. Dropout Characteristics
8
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Figure 6. Dropout Characteristics
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Typical Characteristics (continued)
Unless otherwise specified: TA = 25°C, VIN = VO(NOM) + 1 V, COUT = 2.2 μF, all voltage options, ON/OFF pin tied to VIN.
Figure 7. Dropout Voltage vs Temperature
Figure 8. Dropout Voltage vs Load Current
Figure 9. Ground Pin Current vs Temperature
Figure 10. Ground Pin Current vs Load Current
Figure 12. Input Current vs VIN
Figure 11. Input Current vs VIN
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Typical Characteristics (continued)
Unless otherwise specified: TA = 25°C, VIN = VO(NOM) + 1 V, COUT = 2.2 μF, all voltage options, ON/OFF pin tied to VIN.
10
Figure 13. Line Transient Response
Figure 14. Line Transient Response
Figure 15. Load Transient Response
Figure 16. Load Transient Response
Figure 17. Load Transient Response
Figure 18. Load Transient Response
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Typical Characteristics (continued)
Unless otherwise specified: TA = 25°C, VIN = VO(NOM) + 1 V, COUT = 2.2 μF, all voltage options, ON/OFF pin tied to VIN.
Figure 19. Short Circuit Current
Figure 20. Instantaneous Short Circuit Current vs
Temperature
Figure 21. Short Circuit Current
Figure 22. Output Impedance vs Frequency
Figure 23. Output Impedance vs Frequency
Figure 24. Output Noise Density
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Typical Characteristics (continued)
Unless otherwise specified: TA = 25°C, VIN = VO(NOM) + 1 V, COUT = 2.2 μF, all voltage options, ON/OFF pin tied to VIN.
12
Figure 25. Ripple Rejection
Figure 26. Input to Output Leakage vs Temperature
Figure 27. Output Reverse Leakage vs Temperature
Figure 28. Turnon Waveform
Figure 29. Turnoff Waveform
Figure 30. ON/OFF Pin Current vs VON/OFF
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7 Detailed Description
7.1 Overview
The LP2980-N is a 50-mA, fixed-output voltage regulator designed specifically to meet the requirements of
battery-powered applications. Available in output voltages from 2.5 V to 5 V, the device has an initial output
voltage tolerance of ±0.5% for the A grade (1% for the non-A version). Using an optimized vertically integrated
PNP (VIP) process, the LP2980-N contains these features to facilitate battery-powered designs:
• Fixed 5-V, 4.7-V, 3.3-V, 3-V, and 2.5-V output versions
• Low-dropout voltage, typical dropout of 120 mV at 50-mA load current and 7 mV at 1-mA load
• Low ground current, typically 370 μA at 50-mA load and 80 μA at 1-mA load
• A sleep mode feature is available, allowing the regulator to consume less than 1 µA typically when the
ON/OFF pin is pulled to less than 0.18 V.
• Overtemperature protection and overcurrent protection circuitry is designed to safeguard the device during
unexpected conditions.
7.2 Functional Block Diagram
7.3 Feature Description
7.3.1 Multiple Voltage Options
To meet the different application requirements, the LP2980-N provides multiple fixed output options from 2.5 V to
5 V.
7.3.2 High-Accuracy Output Voltage
With special careful design to minimize all contributions to the output voltage error, the LP2980-N distinguishes
itself as a very high-accuracy output voltage micropower LDO. This includes a tight initial tolerance (0.5%
typical), extremely good line regulation (0.007%/V typical), and a very low output voltage temperature coefficient,
making the part an ideal low-power voltage reference.
7.3.3 Ultra-Low-Dropout Voltage
Generally speaking, the dropout voltage often refers to the voltage difference between the input and output
voltage (VDO = VIN – VOUT), where the main current pass-FET is fully on in the ohmic region of operation and is
characterized by the classic RDS(ON) of the FET. VDO indirectly specifies a minimum input voltage above the
nominal programmed output voltage at which the output voltage is expected to remain within its accuracy
boundary.
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Feature Description (continued)
7.3.4 Low Ground Current
LP2980-N uses a vertical PNP process which allows for quiescent currents that are considerably lower than
those associated with traditional lateral PNP regulators, typically 370 μA at 150-mA load and 80 μA at 1-mA load.
7.3.5 Sleep Mode
When pulling the ON/OFF pin to low level, LP2980-N enters sleep mode, and less than 1-μA quiescent current is
consumed. This function is designed for the application which needs a sleep mode to effectively enhance battery
life cycle.
7.3.6 Short-Circuit Protection (Current Limit)
The internal current-limit circuit is used to protect the LDO against high-load current faults or shorting events. The
LDO is not designed to operate in a steady-state current limit. During a current-limit event, the LDO sources
constant current. Therefore, the output voltage falls when load impedance decreases. If a current limit occurs
and the resulting output voltage is low, excessive power may be dissipated across the LDO resulting in a thermal
shutdown of the output. A foldback feature limits the short-circuit current to protect the regulator from damage
under all load conditions. If OUT is forced below 0 V before EN goes high and the load current required exceeds
the foldback current limit, the device may not start up correctly.
7.3.7 Thermal Protection
The LP2980-N contains a thermal shutdown protection circuit to turn off the output current when excessive heat
is dissipated in the LDO. The thermal time-constant of the semiconductor die is fairly short, and thus the output
cycles on and off at a high rate when thermal shutdown is reached until the power dissipation is reduced. The
internal protection circuitry of the LM2980-N is designed to protect against thermal overload conditions. The
circuitry is not intended to replace proper heat sinking. Continuously running the device into thermal shutdown
degrades its reliability.
7.4 Device Functional Modes
7.4.1 Operation with VOUT(TARGET) + 1 V ≤ VIN < 16 V
The device operates if the input voltage is equal to, or exceeds, VOUT(TARGET) + 0.6 V. At input voltages below the
minimum VIN requirement, the device does not operate correctly and output voltage may not reach target value.
7.4.2 Operation With ON/OFF Control
If the voltage on the ON/OFF pin is less than 0.18 V, the device is disabled, and the shutdown current does not
exceed 1 μA. Raising ON/OFF above 1.6 V initiates the start-up sequence of the device.
14
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8 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
8.1 Application Information
The LP2980-N is a linear voltage regulator operating from 2.1 V to 16 V on the input and regulates voltages
between 2.5 V to 5 V with 0.5% accuracy and 50-mA maximum output current. Efficiency is defined by the ratio
of output voltage to input voltage because the LP2980-N is a linear voltage regulator. To achieve high efficiency,
the dropout voltage (VIN – VOUT) must be as small as possible, thus requiring a very-low-dropout LDO.
Successfully implementing an LDO in an application depends on the application requirements. If the
requirements are simply input voltage and output voltage, compliance specifications (such as internal power
dissipation or stability) must be verified to ensure a solid design. If timing, startup, noise, power supply rejection
ratio (PSRR), or any other transient specification is required, then the design becomes more challenging. This
section discusses the implementation and behavior of the LP2980-N LDO.
8.2 Typical Application
*ON/OFF input must be actively terminated. Tie to IN if this function is not to be used.
**Minimum output capacitance is 1 μF to ensure stability over full load current range. More capacitance provides
superior dynamic performance and additional stability margin (see Output Capacitor Recommendation).
***Do not make connections to this pin.
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Typical Application (continued)
8.2.1 Design Requirements
PARAMETER
DESIGN REQUIREMENT
Input voltage
5 V ±10%, provided by the DC-DC converter switching at 1 MHz
Output voltage
3.3 V ±5%
Output current
50 mA (maximum), 1 mA (minimum)
RMS noise, 300 Hz to 50 kHz
< 1 mVRMS
PSRR at 1 kHz
> 40 dB
8.2.2 Detailed Design Procedure
At 50-mA loading, the dropout of the LP2980-N has 225-mV maximum dropout over temperature, thus an 1700mV headroom is sufficient for operation over both input and output voltage accuracy. The efficiency of the
LP2980-N in this configuration is VOUT / VIN = 66.7%. To achieve the smallest form factor, the SOT-23 package is
selected. Input and output capacitors are selected in accordance with the Output Capacitor Recommendation
section. With an efficiency of 66.7% and a 50-mA maximum load, the internal power dissipation is 85 mW, which
corresponds to a 14.9°C junction temperature rise for the SOT-23 package. With an 85°C maximum ambient
temperature, the junction temperature is at 99.9°C.
8.2.2.1 Output Capacitor Recommendation
Like any low-dropout regulator, the LP2980-N requires an output capacitor to maintain regulator loop stability.
This capacitor must be selected to meet the requirements of minimum capacitance and equivalent series
resistance (ESR) range. It is not difficult to find capacitors which meet the criteria of the LP2980-N, as the
acceptable capacitance and ESR ranges are wider than for most other LDOs.
In general, the capacitor value must be at least 1 μF (over the actual ambient operating temperature), and the
ESR must be within the range indicated in Figure 31, Figure 32, and Figure 33. It should be noted that, although
a maximum ESR is shown in these figures, it is very unlikely to find a capacitor with an ESR that high.
8.2.2.1.1 Tantalum Capacitors
Surface-mountable solid tantalum capacitors offer a good combination of small physical size for the capacitance
value, and an ESR in the range needed by the LP2980-N.
The results of testing the LP2980-N stability with surface-mount solid tantalum capacitors show good stability
with values of at least 1 μF. The value can be increased to 2.2 μF (or more) for even better performance,
including transient response and noise.
Small value tantalum capacitors that have been verified as suitable for use with the LP2980-N are shown in
Table 1. Capacitance values can be increased without limit.
8.2.2.1.2 Aluminum Electrolytic Capacitors
Although probably not a good choice for a production design, because of relatively large physical size, an
aluminum electrolytic capacitor can be used in the design prototype for an LP2980-N regulator. A value of at
least 1 μF should be used, and the ESR must meet the conditions of Figure 31, Figure 32, and Figure 33. If the
operating temperature drops below 0°C, the regulator may not remain stable, as the ESR of the aluminum
electrolytic capacitor will increase and may exceed the limits indicated in Figure 31, Figure 32, and Figure 33.
Table 1. Surface-Mount Tantalum Capacitor Selection Guide
1-μF SURFACE-MOUNT TANTALUM CAPACITORS
16
MANUFACTURER
PART NUMBER
Kemet
T491A105M010AS
NEC
NRU105M10
Siemens
B45196-E3105-K
Nichicon
F931C105MA
Sprague
293D105X0016A2T
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2.2-μF SURFACE-MOUNT TANTALUM CAPACITORS
MANUFACTURER
PART NUMBER
Kemet
T491A225M010AS
NEC
NRU225M06
Siemens
B45196/2.2/10/10
Nichicon
F930J225MA
Sprague
293D225X0010A2T
8.2.2.1.3 Multilayer Ceramic Capacitors
Surface-mountable multilayer ceramic capacitors may be an attractive choice because of their relatively small
physical size and excellent RF characteristics. However, they sometimes have ESR values lower than the
minimum required by the LP2980-N, and relatively large capacitance change with temperature. The
manufacturer's data sheet for the capacitor should be consulted before selecting a value.
Test results of LP2980-N stability using multilayer ceramic capacitors show that a minimum value of 2.2 μF is
usually needed for the 5-V regulator. For the lower output voltages, or for better performance, a higher value
should be used, such as 4.7 μF.
Multilayer ceramic capacitors that have been verified as suitable for use with the LP2980-N are shown in
Table 2.
Table 2. Surface-Mount Multilayer Ceramic Capacitor Selection Guide
2.2-μF SURFACE-MOUNT CERAMIC
MANUFACTURER
PART NUMBER
Tokin
1E225ZY5U-C203
Murata
GRM42-6Y5V225Z16
4.7-μF SURFACE-MOUNT CERAMIC
MANUFACTURER
PART NUMBER
Tokin
1E475ZY5U-C304
Figure 31. 1-μF ESR Range
Figure 32. 2.2-μF ESR Range
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Figure 33. 10-μF ESR Range
8.2.2.2 Reverse Current Path
The internal PNP power transistor used as the pass element in the LP2980-N has an inherent diode connected
between the regulator output and input. During normal operation (where the input voltage is higher than the
output) this diode is reverse biased (see Figure 34).
VIN
VOUT
PNP
GND
Figure 34. LP2980-N Reverse Current Path
However, if the input voltage is more than a VBE below the output voltage, this diode will turn on and current will
flow into the regulator output. In such cases, a parasitic SCR can latch which will allow a high current to flow into
the VIN pin and out the ground pin, which can damage the part.
The internal diode can also be turned on if the input voltage is abruptly stepped down to a voltage which is a VBE
below the output voltage.
In any application where the output voltage may be higher than the input voltage, an external Schottky diode
must be connected from VIN to VOUT (cathode on VIN, anode on VOUT, see Figure 35), to limit the reverse voltage
across the LP2980-N to 0.3 V (see Absolute Maximum Ratings).
18
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SCHOTTKY DIODE
VIN
VOUT
PNP
GND
Figure 35. Adding External Schottky Diode Protection
8.2.2.3 ON/OFF Input Operation
The LP2980-N is shut off by pulling the ON/OFF input low, and turned on by driving the input high. If this feature
is not to be used, the ON/OFF input must be tied to IN to keep the regulator on at all times (the ON/OFF input
must not be left floating).
To ensure proper operation, the signal source used to drive the ON/OFF input must be able to swing above and
below the specified turn-on and turn-off voltage thresholds which ensure an ON or OFF state (see Electrical
Characteristics).
The ON/OFF signal may come from either a totem-pole output, or an open-collector output with a pull-up resistor
to the LP2980-N input voltage or another logic supply. The high-level voltage may exceed the LP2980-N input
voltage, but must remain within the absolute maximum ratings for the ON/OFF pin.
It is also important that the turn-on and turn-off voltage signals applied to the ON/OFF input have a slew rate that
is greater than 40 mV/μs.
NOTE
The regulator shutdown function will not operate correctly if a slow-moving signal is used
to drive the ON/OFF input.
8.2.2.4 Increasing Output Current
The LP2980-N can be used to control higher-current regulators, by adding an external PNP pass transistor. With
the PNP transistors shown in Figure 36, the output current can be as high as 400 mA, as long as the input
voltage is held within the Safe Operation Boundary Curves shown below in Figure 37.
To ensure regulation, the minimum input voltage of this regulator is 6 V. This headroom is the sum of the VBE of
the external transistor and the dropout voltage of the LP2980-N.
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Figure 36. 5-V and 400-mA Regulator
Notes:
Note A: Drive this input with a logic signal (see ON/OFF Input Operation). If the shutdown function is not to be
used, tie the ON/OFF pin directly to the IN pin.
Note B: Recommended devices (other PNP transistors can be used if the current gain and voltage ratings are
similar).
Note C: Capacitor is required for regulator stability. Minimum size is shown, and may be increased without limit.
Note D: Increasing the output capacitance improves transient response and increases phase margin.
Note E: Maximum safe input voltage and load current are limited by power dissipation in the PNP pass transistor
and the maximum ambient temperature for the specific application. If a TO-92 transistor such as the MPS2907A
is used, the thermal resistance from junction-to-ambient is 180°C/W in still air.
Assuming a maximum allowable junction temperature of 150°C for the MPS2907A device, the following curves
show the maximum VIN and IL values that may be safely used for several ambient temperatures.
Figure 37. Safe Operation Boundary Curves for Figure 36
With limited input voltage range, the LP2980-N can control a 3.3-V, 3-A regulator with the use of a high currentgain external PNP pass transistor as shown in Figure 38. If the regulator is to be loaded with the full 3 A, heat
sinking will be required on the pass transistor to keep it within its rated temperature range. See Figure 39. For
best load regulation at the high load current, the LP2980-N output voltage connection should be made as close
to the load as possible.
20
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Although this regulator can handle a much higher load current than can the LP2980-N alone, it can be shut down
in the same manner as the LP2980-N. When the ON/OFF control is brought low, the converter will be in
shutdown, and will draw less than 1 μA from the source.
Figure 38. 5 V to 3.3 V at 3-A Converter
NOTES:
Note A: Drive this input with a logic signal (see ON/OFF Input Operation). If the shutdown function is not to be
used, tie the ON/OFF pin directly to the IN pin.
Note B: Capacitor is required for regulator stability. Minimum size is shown, and may be increased without limit.
Note C: Increasing the output capacitance improves transient response and increases phase margin.
Note D: A heatsink may be required for this transistor. The maximum allowable value for thermal resistance of
the heatsink is dependent on ambient temperature and load current (see curves in Figure 39). Once the value is
obtained from the graph, a heatsink must be selected which has a thermal resistance equal to or lower than this
value. If the value is above 60°C/W, no heatsink is required.
For these curves, a maximum junction temperature of 150°C is assumed for the pass transistor. The case-toheatsink attachment thermal resistance is assumed to be 1.5°C/W. All calculations are for 5.5-V input voltage
(which is worst-case for power dissipation).
Figure 39. Heatsink Thermal Resistance Requirements for Figure 38
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8.2.3 Application Curve
Figure 40. Load Transient Response
22
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9 Power Supply Recommendations
The LP2980-N is designed to operate from an input voltage supply range between 2.1 V and 16 V. The input
voltage range provides adequate headroom for the device to have a regulated output. This input supply must be
well regulated. If the input supply is noisy, additional input capacitors with low ESR can help improve the output
noise performance.
10 Layout
10.1 Layout Guidelines
For best overall performance, place all circuit components on the same side of the circuit board and as near as
practical to the respective LDO pin connections. Place ground return connections to the input and output
capacitors, and to the LDO ground pin as close as possible to each other, connected by a wide, component-side,
copper surface. The use of vias and long traces to create LDO circuit connections is strongly discouraged and
negatively affects system performance. This grounding and layout scheme minimizes inductive parasitics, and
thereby reduces load-current transients, minimizes noise, and increases circuit stability. A ground reference
plane is also recommended and is either embedded in the PCB itself or located on the bottom side of the PCB
opposite the components. This reference plane serves to assure accuracy of the output voltage, shield noise,
and behaves similar to a thermal plane to spread (or sink) heat from the LDO device. In most applications, this
ground plane is necessary to meet thermal requirements.
10.2 Layout Example
VIN
VOUT
Input
Capacitor
IN
GND
OUT
Output
Capacitor
Ground
ON/OFF
ON/OFF
NC
Figure 41. LP2980-N Layout Example
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LP2980-N
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11 Device and Documentation Support
11.1 Device Support
11.1.1 Third-Party Products Disclaimer
TI'S PUBLICATION OF INFORMATION REGARDING THIRD-PARTY PRODUCTS OR SERVICES DOES NOT
CONSTITUTE AN ENDORSEMENT REGARDING THE SUITABILITY OF SUCH PRODUCTS OR SERVICES
OR A WARRANTY, REPRESENTATION OR ENDORSEMENT OF SUCH PRODUCTS OR SERVICES, EITHER
ALONE OR IN COMBINATION WITH ANY TI PRODUCT OR SERVICE.
11.2 Receiving Notification of Documentation Updates
To receive notification of documentation updates, navigate to the device product folder on ti.com. In the upper
right corner, click on Alert me to register and receive a weekly digest of any product information that has
changed. For change details, review the revision history included in any revised document.
11.3 Community Resources
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of
Use.
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help
solve problems with fellow engineers.
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and
contact information for technical support.
11.4 Trademarks
E2E is a trademark of Texas Instruments.
All other trademarks are the property of their respective owners.
11.5 Electrostatic Discharge Caution
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.
11.6 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
12 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
24
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PACKAGE OPTION ADDENDUM
www.ti.com
10-Dec-2022
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
Samples
(4/5)
(6)
LP2980AIM5-2.5
LIFEBUY
SOT-23
DBV
5
1000
Non-RoHS
& Green
Call TI
Level-1-260C-UNLIM
-40 to 125
L0NA
LP2980AIM5-2.5/NOPB
ACTIVE
SOT-23
DBV
5
1000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
L0NA
LP2980AIM5-3.0
NRND
SOT-23
DBV
5
1000
Non-RoHS
& Green
Call TI
Level-1-260C-UNLIM
-40 to 125
L02A
LP2980AIM5-3.0/NOPB
ACTIVE
SOT-23
DBV
5
1000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
L02A
LP2980AIM5-3.3
NRND
SOT-23
DBV
5
1000
Non-RoHS
& Green
Call TI
Level-1-260C-UNLIM
-40 to 125
L00A
LP2980AIM5-3.3/NOPB
ACTIVE
SOT-23
DBV
5
1000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
L00A
Samples
LP2980AIM5-4.7/NOPB
ACTIVE
SOT-23
DBV
5
1000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
L37A
Samples
LP2980AIM5-5.0
NRND
SOT-23
DBV
5
1000
Non-RoHS
& Green
Call TI
Level-1-260C-UNLIM
-40 to 125
L01A
LP2980AIM5-5.0/NOPB
ACTIVE
SOT-23
DBV
5
1000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
L01A
LP2980AIM5X-2.5
NRND
SOT-23
DBV
5
3000
Non-RoHS
& Green
Call TI
Level-1-260C-UNLIM
-40 to 125
L0NA
LP2980AIM5X-2.5/NOPB
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
L0NA
Samples
LP2980AIM5X-3.0/NOPB
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
L02A
Samples
LP2980AIM5X-3.3
NRND
SOT-23
DBV
5
3000
Non-RoHS
& Green
Call TI
Level-1-260C-UNLIM
-40 to 125
L00A
LP2980AIM5X-3.3/NOPB
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
L00A
Samples
LP2980AIM5X-4.7/NOPB
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
L37A
Samples
LP2980AIM5X-5.0/NOPB
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
L01A
Samples
LP2980IM5-2.5/NOPB
LIFEBUY
SOT-23
DBV
5
1000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
L0NB
LP2980IM5-3.0/NOPB
ACTIVE
SOT-23
DBV
5
1000
RoHS & Green
NIPDAU | SN
Level-1-260C-UNLIM
-40 to 125
L02B
LP2980IM5-3.3
NRND
SOT-23
DBV
5
1000
Non-RoHS
& Green
Call TI
Level-1-260C-UNLIM
-40 to 125
L00B
Addendum-Page 1
Samples
Samples
Samples
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
Orderable Device
10-Dec-2022
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
Samples
(4/5)
(6)
LP2980IM5-3.3/NOPB
ACTIVE
SOT-23
DBV
5
1000
RoHS & Green
NIPDAU | SN
Level-1-260C-UNLIM
-40 to 125
L00B
LP2980IM5-3.8/NOPB
LIFEBUY
SOT-23
DBV
5
1000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
L21B
LP2980IM5-4.7/NOPB
LIFEBUY
SOT-23
DBV
5
1000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
L37B
LP2980IM5-5.0
LIFEBUY
SOT-23
DBV
5
1000
Non-RoHS
& Green
Call TI
Level-1-260C-UNLIM
-40 to 125
L01B
LP2980IM5-5.0/NOPB
ACTIVE
SOT-23
DBV
5
1000
RoHS & Green
NIPDAU | SN
Level-1-260C-UNLIM
-40 to 125
L01B
Samples
LP2980IM5X-2.5/NOPB
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
L0NB
Samples
LP2980IM5X-3.0/NOPB
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
NIPDAU | SN
Level-1-260C-UNLIM
-40 to 125
L02B
Samples
LP2980IM5X-3.3
NRND
SOT-23
DBV
5
3000
Non-RoHS
& Green
Call TI
Level-1-260C-UNLIM
-40 to 125
L00B
LP2980IM5X-3.3/NOPB
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
NIPDAU | SN
Level-1-260C-UNLIM
-40 to 125
L00B
Samples
LP2980IM5X-5.0/NOPB
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
NIPDAU | SN
Level-1-260C-UNLIM
-40 to 125
L01B
Samples
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of
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