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LP2952-N, LP2952A, LP2953, LP2953A
SNVS095F – MAY 2004 – REVISED MARCH 2015
LP295x Adjustable Micropower Low-Dropout Voltage Regulators
1 Features
3 Description
•
•
•
•
•
•
•
•
•
•
•
The LP2952 and LP2953 are micropower voltage
regulators with very low quiescent current (130 μA
typical at 1-mA load) and very low dropout voltage
(typically 60 mV at light load and 470 mV at 250-mA
load current). They are ideally suited for batterypowered systems. Furthermore, the quiescent current
increases only slightly at dropout, which prolongs
battery life.
1
2.3-V to 30-V Input Voltage Range
Output Voltage Adjusts from 1.23 V to 29 V
250-mA Output Current
Extremely Low Quiescent Current
Low Dropout Voltage
Extremely Tight Line and Load Regulation
Very Low Temperature Coefficient
Current and Thermal Limiting
Reverse Battery-Input Protection
50-mA (Typical) Automatic Output Discharge
LP2953 Versions Only
– Auxiliary Comparator Included With CMOSand TTL-Compatible Output Levels. Can Be
Used for Fault Detection, Low-Input Line
Detection, and so on.
2 Applications
•
•
•
•
High-Efficiency Linear Regulator
Regulator With Undervoltage Shutdown
Low-Dropout Battery-Powered Regulator
Snap-ON/Snap-OFF Regulator
The LP2952 and LP2953 retain all the desirable
characteristics of the LP2951, but offer increased
output current, additional features, and an improved
shutdown function.
The automatic output discharge pulls the output down
quickly when the shutdown is activated.
The error flag goes low if the output voltage drops out
of regulation.
Reverse battery-input protection is provided.
The internal voltage reference is made available for
external use, providing a low temperature coefficient
(20 ppm/°C) reference with very good line (0.03%)
and load (0.04%) regulation.
Device Information(1)
PART NUMBER
LP2952x
LP2953x
PACKAGE
BODY SIZE (NOM)
SOIC (16)
9.90 mm × 3.91 mm
SOIC (16)
9.90 mm × 3.91 mm
PDIP (16)
21.755 mm × 6.35 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Typical Application Schematic
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.
LP2952-N, LP2952A, LP2953, LP2953A
SNVS095F – MAY 2004 – REVISED MARCH 2015
www.ti.com
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
6.7
6.8
4
4
4
5
5
5
6
9
Absolute Maximum Ratings ......................................
ESD Ratings..............................................................
Recommended Operating Conditions.......................
Thermal Information ..................................................
Electrical Characteristics: 3.3-V Versions .................
Electrical Characteristics: 5-V Versions ....................
Electrical Characteristics: All Voltage Options ..........
Typical Characteristics ..............................................
Detailed Description ............................................ 14
7.1 Overview ................................................................. 14
7.2 Functional Block Diagrams ..................................... 14
7.3 Feature Description................................................. 15
7.4 Device Functional Mode ......................................... 16
8
Application and Implementation ........................ 17
8.1 Application Information............................................ 17
8.2 Typical Applications ................................................ 21
9 Power Supply Recommendations...................... 30
10 Layout................................................................... 31
10.1 Layout Guidelines ................................................. 31
10.2 Layout Example .................................................... 31
10.3 Power Dissipation: Heatsink Requirements
(Industrial Temperature Range Devices) ................. 32
11 Device and Documentation Support ................. 34
11.1
11.2
11.3
11.4
Related Links ........................................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
34
34
34
34
12 Mechanical, Packaging, and Orderable
Information ........................................................... 34
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision E (December 2014) to Revision F
Page
•
Deleted "Assured" .................................................................................................................................................................. 1
•
Changed "Output Pulldown Crowbar" to "Automatic Output Discharge" ............................................................................... 1
•
Changed "internal crowbar" to "automatic output discharge" ................................................................................................. 1
•
Added word "input" after "battery" in Features and Description ............................................................................................. 1
•
Changed pin names for IN and OUT to match TI nomenclature; fix typos ............................................................................ 1
•
Changed max junc. temp from 125°C to 150°C .................................................................................................................... 4
•
Changed wording of footnote 12 ........................................................................................................................................... 8
•
Added second bullet for "LP2953 versions only" ................................................................................................................. 14
•
Added Automatic Output Dischange subsection ................................................................................................................. 16
•
Deleted sentence "To achieve the smallest form factor, the TO-92 package is selected.".................................................. 22
•
Changed "With an efficiency of 83.3% and a 250-mA maximum load, the internal power dissipation is 250 mW,
which corresponds to a 19.2°C junction temperature rise for the SOIC package." to "With a VIN – VOUT differential of
1 V and a maximum load current of 250 mA the internal junction temperature (TJ) of the SOIC package will rise
19.2° above the ambient temperature."................................................................................................................................ 22
•
Deleted "Thermal Resistance for Various Copper Heatsinking Patterns" table ................................................................... 33
Changes from Revision D (September 2013) to Revision E
•
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; updated
Thermal Information values; deleted obsolete LP2953AM references .................................................................................. 1
Changes from Revision C (March 2005) to Revision D
•
2
Page
Changed layout of National Data Sheet to TI format ........................................................................................................... 30
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SNVS095F – MAY 2004 – REVISED MARCH 2015
5 Pin Configuration and Functions
16 Pins
LP2952 SOIC (D) Package
Top View
16 Pins
LP2953 SOIC (D) Package
Top View
16 Pins
LP2953 PDIP (NBG) Package
Top View
Pin Functions LP2952-N
PIN
NAME
SOIC(D)
I/O
DESCRIPTION
ERROR
6
O
Error signal output
FEEDBACK
14
I
Error amplifier noninverting input
1, 8, 9, 16
-
Ground
GROUND
IN
15
I
Regulator power input
NC
2, 7, 10, 11
-
NC
OUT
3
O
Regulated output voltage
REFERENCE
12
O
Internal reference voltage output
SENSE
4
I
Feedback voltage sense input
SHUTDOWN
5
I
Shutdown input
VTAP
13
I
Internal resistor divider input
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LP2952-N, LP2952A, LP2953, LP2953A
SNVS095F – MAY 2004 – REVISED MARCH 2015
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Pin Functions LP2953
PIN
NAME
I/O
DESCRIPTION
SOIC(D)
PDIP(NBG)
COMPIN
10
15
I
Auxiliary comparator input
COMPOUT
11
14
O
Auxiliary comparator output
ERROR
6
10
O
Error signal output
FEEDBACK
14
2
I
Error amplifier noninverting input
1, 8, 9, 16
4, 5, 12, 13
-
Ground
IN
15
3
I
Regulator power input
NC
GROUND
2, 7
7, 11
-
NC
OUT
3
6
O
Regulated output voltage
REFERENCE
12
16
O
Internal reference voltage output
SENSE
4
8
I
Feedback voltage sense input
SHUTDOWN
5
9
I
Shutdown input
VTAP
13
1
I
Internal resistor divider input
6 Specifications
6.1 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted) (1)
MIN
Power dissipation (2)
MAX
UNIT
Internally Limited
−20
Input supply voltage
30
V
−0.3
5
V
−0.3
30
V
SHUTDOWN input voltage (4)
−0.3
30
V
(4)
−0.3
(3)
Comparator input voltage (4)
FEEDBACK input voltage
Comparator output voltage
Maximum junction temperature
−65
Storage temperature, Tstg
(1)
(2)
(3)
(4)
30
V
150
°C
150
°C
Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended
Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
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 the equation for P(MAX): P(MAX) = (TJ(MAX) – TA) / RθJA.
Exceeding the maximum allowable power dissipation will cause excessive die temperature, and the regulator will go into thermal
shutdown. See Power Supply Recommendations for additional information on heatsinking and thermal resistance.
When used in dual-supply systems where the regulator load is returned to a negative supply, the output voltage must be diode-clamped
to ground.
May exceed the input supply voltage.
6.2 ESD Ratings
VALUE
V(ESD)
(1)
Electrostatic
discharge
Human body model (HBM), per ANSI/ESDA/JEDEC JS-001, all pins (1)
±2000
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
4
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MIN
MAX
UNIT
−40
125
°C
2.3
30
V
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SNVS095F – MAY 2004 – REVISED MARCH 2015
6.4 Thermal Information
LP2952, LP2953
LP2953
SOIC (D)
PDIP (NBG)
THERMAL METRIC (1)
UNIT
16 PINS
RθJA
Junction-to-ambient thermal resistance
76.9
42.1
RθJC(top)
Junction-to-case (top) thermal resistance
37.4
28.1
RθJB
Junction-to-board thermal resistance
34.6
22.2
ψJT
Junction-to-top characterization parameter
7.3
12.0
ψJB
Junction-to-board characterization parameter
34.3
22.1
(1)
°C/W
For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.
6.5 Electrical Characteristics: 3.3-V Versions
Limits are assured by production testing or correlation techniques using standard Statistical Quality Control (SQC) methods.
Unless otherwise specified: MIN (minimum) and MAX (maximum) specifications in apply over the full Operating Temperature
Range and TYP (typical) values apply at TJ = 25°C, VIN = VOUT(NOM) + 1 V, IOUT = 1 mA, COUT = 2.2 μF for 5-V parts and 4.7
μF for 3.3-V parts. FEEDBACK pin is tied to VTAP pin, OUT pin is tied to SENSE pin.
PARAMETER
TEST CONDITIONS
LP2952AI-3.3, LP2953AI-3.3
TJ = 25°C
VOUT
Output voltage
1 mA ≤ IOUT ≤ 250 mA
LP2952I-3.3, LP2953I-3.3
MIN
TYP
MAX
MIN
TYP
MAX
3.284
3.3
3.317
3.267
3.3
3.333
3.260
3.3
3.340
3.234
3.3
3.366
3.254
3.3
3.346
3.221
3.3
3.379
UNIT
V
6.6 Electrical Characteristics: 5-V Versions
Limits are assured by production testing or correlation techniques using standard Statistical Quality Control (SQC) methods.
Unless otherwise specified, MIN (minimum) and MAX (maximum) specifications in apply over the full Operating Temperature
Range and TYP (typical) values apply at TJ = 25°C, VIN = VOUT(NOM) + 1 V, IOUT = 1 mA, COUT = 2.2 μF for 5-V parts and 4.7
μF for 3.3-V parts. FEEDBACK pin is tied to VTAP pin, OUT pin is tied to SENSE pin.
PARAMETER
TEST CONDITIONS
TJ = 25°C
VOUT
Output voltage
1 mA ≤ IOUT ≤ 250 mA
Copyright © 2004–2015, Texas Instruments Incorporated
LP2952AI, LP2953AI
LP2952I, LP2953I
MIN
TYP
MAX
MIN
TYP
MAX
4.975
5
5.025
4.95
5
5.05
4.94
5
5.06
4.9
5
5.1
4.93
5
5.07
4.88
5
5.12
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UNIT
V
5
LP2952-N, LP2952A, LP2953, LP2953A
SNVS095F – MAY 2004 – REVISED MARCH 2015
www.ti.com
6.7 Electrical Characteristics: All Voltage Options
Limits are assured by production testing or correlation techniques using standard Statistical Quality Control (SQC) methods.
Unless otherwise specified, MIN (minimum) and MAX (maximum) specifications in apply over the full Operating Temperature
Range and TYP (typical) values apply at TJ = 25°C, VIN = VOUT(NOM) + 1 V, IOUT = 1 mA, COUT = 2.2 μF for 5-V parts and 4.7
μF for 3.3-V parts. FEEDBACK pin is tied to VTAP pin, OUT pin is tied to SENSE pin.
PARAMETER
TEST CONDITIONS
LP2952AI, LP2953AI,
LP2952AI-3.3, LP2953AI-3.3 (1)
MIN
LP2952I, LP2953I,
LP2952I-3.3, LP2953I-3.3
MIN
TYP
UNIT
TYP
MAX
MAX
20
100
20
TJ = 25°C
VIN = VOUT(NOM) + 1 V to 30 V
0.03%
0.1%
0.03%
0.2%
VIN = VOUT(NOM) + 1 V to 30 V
0.03%
0.2%
0.03%
0.4%
TJ = 25°C
IOUT = 1 mA to 250 mA
0.04%
0.16%
0.04%
0.20%
IOUT = 0.1 mA to 1 mA
REGULATOR
ûVOUT
ûT
Output voltage
temperature
coefficient
ûVOUT
ûV
Output voltage
line regulation
ûVOUT
ûV
Output voltage
load regulation (3)
VIN – VOUT
IGND
Dropout
voltage (4)
Ground pin
current (5)
See (2)
0.04%
0.20%
0.04%
0.30%
TJ = 25°C, IOUT = 1 mA
60
100
60
100
IOUT = 1 mA
60
150
60
150
IOUT = 50 mA
240
300
240
300
IOUT = 50 mA
240
420
240
420
TJ = 25°C, IOUT = 100 mA
310
400
310
400
IOUT = 100 mA
310
520
310
520
TJ = 25°C, IOUT = 250 mA
470
600
470
600
IOUT = 250 mA
470
800
470
800
TJ = 25°C, IOUT = 1 mA
130
170
130
170
IOUT = 1 mA
130
200
130
200
TJ = 25°C, IOUT = 50 mA
1.1
2
1.1
2
IOUT = 50 mA
1.1
2.5
1.1
2.5
TJ = 25°C, IOUT = 100 mA
4.5
6
4.5
6
IOUT = 100 mA
4.5
8
4.5
8
TJ = 25°C, IOUT = 250 mA
21
28
21
28
IOUT = 250 mA
IGND
Ground pin
current at
dropout
IGND
Ground pin
current at
shutdown (5)
ILIMIT
Current limit
ûVOUT
ûPD
Thermal
regulation
(1)
(2)
(3)
(4)
(5)
(6)
6
150 ppm/°C
21
33
21
33
VIN = VOUT(NOM) − 0.5 V
165
210
165
210
IOUT = 100 μA
–40°C ≤ TJ ≤ 125°C
165
240
165
240
TJ = 25°C, VSHUTDOWN ≤ 1.1 V
105
140
105
140
TJ = 25°C, VOUT = 0
380
500
380
500
VOUT = 0
380
530
380
530
TJ = 25°C; see (6)
0.05
0.2
0.05
0.2
mV
μA
mA
μA
μA
mA
%/W
Drive SHUTDOWN pin with TTL or CMOS low level to shut off regulator, high level to turn on regulator.
Output or reference voltage temperature coefficient is defined as the worst-case voltage change divided by the total temperature range.
Load regulation is measured at constant junction temperature using low duty-cycle pulse testing. Two separate tests are performed, one
for the range of IOUT = 100 μA to 1 mA and one for the range of IOUT =1 mA to 250 mA. Changes in output voltage due to heating
effects are covered by the thermal regulation specification.
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. At very low values of programmed output voltage, the input voltage minimum of 2 V (2.3 V over temperature) must be
observed.
Ground pin current is the regulator quiescent current. The total current drawn from the source is the sum of the ground pin current,
output load current, and current through the external resistive divider (if used).
Thermal regulation is the change in output voltage at a time t after a change in power dissipation, excluding load or line regulation
effects. Specifications are for a 200-mA load pulse at VIN = VOUT(NOM) + 15 V (3-W pulse) for t = 10 ms.
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SNVS095F – MAY 2004 – REVISED MARCH 2015
Electrical Characteristics: All Voltage Options (continued)
Limits are assured by production testing or correlation techniques using standard Statistical Quality Control (SQC) methods.
Unless otherwise specified, MIN (minimum) and MAX (maximum) specifications in apply over the full Operating Temperature
Range and TYP (typical) values apply at TJ = 25°C, VIN = VOUT(NOM) + 1 V, IOUT = 1 mA, COUT = 2.2 μF for 5-V parts and 4.7
μF for 3.3-V parts. FEEDBACK pin is tied to VTAP pin, OUT pin is tied to SENSE pin.
PARAMETER
LP2952AI, LP2953AI,
LP2952AI-3.3, LP2953AI-3.3 (1)
TEST CONDITIONS
MIN
en
VREF
TYP
LP2952I, LP2953I,
LP2952I-3.3, LP2953I-3.3
MAX
MIN
TYP
Output noise
voltage (10 Hz
to 100 kHz)
IOUT = 100 mA
COUT = 4.7 μF
400
400
COUT = 33 μF
260
260
Reference
voltage
TJ = 25°C, see (8)
Reference
voltage line
regulation
VIN = 2.5 V to VOUT + 1 V
Reference
voltage load
regulation
Reference
voltage
temperature
coefficient
COUT = 33 μF
(7)
80
1.215
(8)
see ,
1.23
1.205
UNIT
MAX
μV
RMS
80
1.245
1.205
1.255
1.19
1.23
1.255
0.03%
0.1%
0.03%
0.2%
0.03%
0.2%
0.03%
0.4%
TJ = 25°C, IREF = 0 to 200 μA
0.25%
0.4%
0.25%
0.8%
IREF = 0 to 200 μA
0.25%
0.6%
0.25%
1.0%
VIN = VOUT(NOM)+ 1 V to 30 V
(9)
See (2), –40°C ≤ TJ ≤ 125°C
20
TJ = 25°C
20
40
20
40
20
60
20
60
IB(FB)
Feedback pin
bias current
IO(SINK)
TJ = 25°C; see
Output off
pulldown current See (10)
(10)
20
30
30
20
20
V
1.27
ppm/°C
nA
mA
DROPOUT DETECTION COMPARATOR
Output high
leakage
IOH
Output low
voltage
VOL
TJ = 25°C, VOH = 30 V
0.01
1
0.01
1
VOH = 30 V
0.01
2
0.01
2
TJ = 25°C, VIN = VOUT(NOM) −
0.5 V
IOUT(COMP) = 400 μA
150
250
150
250
VIN = VOUT(NOM) − 0.5 V
IOUT(COMP) = 400 μA
150
400
−80
−60
−35
−95
−60
−25
(11)
mV
150
400
−80
−60
−35
−95
−60
−25
VTHR(MAX)
Upper threshold
voltage
TJ = 25°C, see
VTHR(MIN)
Lower threshold
voltage
TJ = 25°C, see (11)
−110
−85
−55
−110
−85
−55
See (11)
−160
−85
−40
−160
−85
−40
HYST
Hysteresis
See (11)
(7)
(8)
(9)
(10)
(11)
See (11)
μA
15
15
mV
mV
mV
Connect a 0.1-μF capacitor from the OUT pin to the FEEDBACK pin.
VREF ≤ VOUT ≤ (VIN − 1 V), 2.3 V ≤ VIN ≤ 30 V, 100 μA ≤ IOUT ≤ 250 mA.
Two separate tests are performed, one covering 2.5 V ≤ VIN ≤ VOUT(NOM)) + 1 V and the other test for VOUT(NOM) + 1 V ≤ VIN ≤ 30 V.
VSHUTDOWN ≤ 1.1 V, VOUT = VOUT(NOM)
Comparator thresholds are expressed in terms of a voltage differential at the FEEDBACK pin below the nominal reference voltage
measured at VIN = VOUT(NOM) + 1 V. To express these thresholds in terms of output voltage change, multiply by the error amplifier gain,
which is VOUT / VREF = (R1 + R2) / R2 (see Figure 31).
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SNVS095F – MAY 2004 – REVISED MARCH 2015
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Electrical Characteristics: All Voltage Options (continued)
Limits are assured by production testing or correlation techniques using standard Statistical Quality Control (SQC) methods.
Unless otherwise specified, MIN (minimum) and MAX (maximum) specifications in apply over the full Operating Temperature
Range and TYP (typical) values apply at TJ = 25°C, VIN = VOUT(NOM) + 1 V, IOUT = 1 mA, COUT = 2.2 μF for 5-V parts and 4.7
μF for 3.3-V parts. FEEDBACK pin is tied to VTAP pin, OUT pin is tied to SENSE pin.
PARAMETER
TEST CONDITIONS
LP2952AI, LP2953AI,
LP2952AI-3.3, LP2953AI-3.3 (1)
LP2952I, LP2953I,
LP2952I-3.3, LP2953I-3.3
UNIT
MIN
TYP
MAX
MIN
TYP
MAX
−7.5
±3
7.5
−7.5
±3
7.5
10
−10
SHUTDOWN INPUT (12)
VOS
HYST
IB
Input offset
voltage
TJ = 25°C
(Referred to VREF)
−10
Hysteresis
Input bias
current
6
TJ = 25°C
VIN(SD) = 0 V to 5 V
−30
VIN(SD) = 0 V to 5 V
−50
10
6
30
−30
50
−50
mV
10
10
mV
−30
nA
50
AUXILIARY COMPARATOR (LP2953 Only)
VOS
HYST
IB
Input offset
voltage
TJ = 25°C
(Referred to VREF)
−7.5
±3
7.5
−7.5
±3
7.5
(Referred to VREF)
−10
±3
10
−10
±3
10
Hysteresis
Input bias
current
6
6
mV
mV
TJ = 25°C, VIN(COMP) = 0 V to 5
V
−30
10
30
−30
10
30
VIN(COMP) = 0 V to 5 V
−50
10
50
−50
10
50
IOH
Output high
leakage
TJ = 25°C, VOH = 30 V
0.01
1
0.01
1
VIN(COMP) = 1.3 V
0.01
2
0.01
2
VOL
Output low
voltage
TJ = 25°C, VIN(COMP) = 1.1 V
150
250
150
250
IOUT(COMP) = 400 μA
150
400
150
400
nA
μA
mV
(12) Drive SHUTDOWN pin with TTL or CMOS-low level to shut regulator OFF, high level to turn regulator ON.
8
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6.8 Typical Characteristics
Unless otherwise specified: VIN = 6 V, IOUT = 1 mA, COUT = 2.2 μF, VSD = 3 V, TA = 25°C, VOUT = 5 V.
Figure 1. Quiescent Current
Figure 2. Quiescent Current
Figure 3. Ground Pin Current vs Load
Figure 4. Ground Pin Current
Figure 5. Ground Pin Current
Figure 6. Output Noise Voltage
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Typical Characteristics (continued)
Unless otherwise specified: VIN = 6 V, IOUT = 1 mA, COUT = 2.2 μF, VSD = 3 V, TA = 25°C, VOUT = 5 V.
10
Figure 7. Ripple Rejection
Figure 8. Ripple Rejection
Figure 9. Ripple Rejection
Figure 10. Line Transient Response
Figure 11. Line Transient Response
Figure 12. Output Impedance
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Typical Characteristics (continued)
Unless otherwise specified: VIN = 6 V, IOUT = 1 mA, COUT = 2.2 μF, VSD = 3 V, TA = 25°C, VOUT = 5 V.
Figure 13. Load Transient Response
Figure 14. Load Transient Response
Figure 15. Dropout Characteristics
Figure 16. Enable Transient
Figure 17. Enable Transient
Figure 18. Short-Circuit Output Current and Maximum
Output Current
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Typical Characteristics (continued)
Unless otherwise specified: VIN = 6 V, IOUT = 1 mA, COUT = 2.2 μF, VSD = 3 V, TA = 25°C, VOUT = 5 V.
12
Figure 19. Feedback Bias Current
Figure 20. FEEDBACK Pin Current
Figure 21. Error Output
Figure 22. Comparator Sink Current
Figure 23. Divider Resistance
Figure 24. Dropout Detection Comparator Threshold
Voltages
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Typical Characteristics (continued)
Unless otherwise specified: VIN = 6 V, IOUT = 1 mA, COUT = 2.2 μF, VSD = 3 V, TA = 25°C, VOUT = 5 V.
Figure 25. Thermal Regulation
Figure 26. Minimum Operating Voltage
Figure 27. Dropout Voltage
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7 Detailed Description
7.1 Overview
The LP2952 and LP2953 are very high accuracy micropower voltage regulators with low quiescent current (130
μA, typical) and low dropout voltage (typically 60 mV at light loads and 490 mV at 250 mA). They are ideally
suited for use in battery-powered systems.
The LP2952 and LP2953 block diagram contains several features, including:
• Very high accuracy 1.23-V reference.
• Internal protection circuitry, such as thermal foldback current limit, thermal shutdown protection, and reverse
battery-input protection.
• Fixed 5-V and 3.3-V versions.
• Error flag output which may be used for a power-on reset.
• Shutdown input, allowing turn off the regulator when the SHUTDOWN pin is pulled low.
LP2953 versions only:
• An auxiliary comparator is designed for customer special purpose when shutdown is activated, this is a
CMOS- or TTL-compatible output level.
• Automatic output discharge when the SHUTDOWN pin is pulled low.
7.2 Functional Block Diagrams
Figure 28. LP2952 Block Diagram
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Functional Block Diagrams (continued)
Figure 29. LP2953 Block Diagram
7.3 Feature Description
7.3.1 Fixed Voltage Options and Programmable Voltage Version
The LP2952 and LP2953 provide 2 fixed output options: 3.3 V and 5 V. To meet different requirements for the
application, they can also be used as programmable voltage regulators with external resistor networks; see
Application Information for more details.
7.3.2 High-Accuracy Output Voltage
With special and careful design to minimize all contributions to the output voltage error, the LP2952 and LP2953
distinguished themselves as very high output voltage accuracy micropower LDO. This includes a tight initial
tolerance (0.5% typical), extremely good load and line regulation, and a very low output voltage temperature
coefficient, making the part an ideal a low-power voltage reference.
7.3.3 Error Detection Comparator Output
The LP2952 and LP2953 will generate a logic low output when the output falls out of regulation by more than
approximately 5%. See Application Information for more details.
7.3.4 Auxiliary Comparator
An auxiliary comparator is designed for customer special purpose when shutdown is activated. This block is still
active and can be used to generate fault detection, low input line detection signal for system controllers. The
comparator output level is CMOS- or TTL-compatible. See Application Information for more details.
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Feature Description (continued)
7.3.5
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. Note also that 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 thermal foldback feature limits the short-circuit current to protect the
regulator from damage under all load conditions. If the OUT pin is forced below 0 V before SHUTDOWN goes
high and the load current required exceeds the thermal foldback current limit, the device may not start up
correctly.
7.3.6 Thermal Protection
The device 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 device is designed to protect against thermal overload conditions. The circuitry
is not intended to replace a proper heatsink. Continuously running the device into thermal shutdown degrades its
reliability.
7.3.7 Automatic Output Discharge
Both LP2952 and LP2953 employ an internal 50-mA (typical) pulldown to discharge the output when the
SHUTDOWN pin is low and the output is disabled.
7.4 Device Functional Mode
7.4.1 Shutdown Mode
When pulling the SHUTDOWN pin to low level, the LP2952 and LP2953 will enter shutdown mode, and a very
low quiescent current is consumed. This function is designed for applications which needs a shutdown mode to
effectively enhance battery life cycle. When the SHUTDOWN pin is low the automatic output discharge circuity
will be active. See Application Information for more details.
7.4.2 Operation with 30 V ≥ VIN > VOUT(TARGET) + 1 V
The device operate if the input voltage is equal to, or exceeds, VOUT(TARGET) + 1 V, and SHUTDOWN is pulled to
high level. At input voltages below the minimum VIN requirement, the devices do not operate correctly and output
voltage may not reach target value.
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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
Figure 30. Schematic Diagram
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Application Information (continued)
8.1.1 External Capacitors
A 2.2-μF (or greater) capacitor is required between the OUT pin and ground to assure stability when the output is
set to 5 V. Without this capacitor, the device will oscillate. Most types of tantalum or aluminum electrolytic
capacitors will work here. Film types will work, but are more expensive. Many aluminum electrolytic capacitors
contain electrolytes which freeze at −30°C, which requires the use of solid tantalum capacitors below −25°C. The
important parameters of the capacitor are an equivalent series resistance (ESR) of about 5 Ω or less and a
resonant frequency above 500 kHz (the ESR may increase by a factor of 20 or 30 as the temperature is reduced
from 25°C to −30°C). The value of this capacitor may be increased without limit.
At lower values of output current, less output capacitance is required for stability. The capacitor can be reduced
to 0.68 μF for currents below 10 mA or 0.22 μF for currents below 1 mA.
Programming the output for voltages below 5 V runs the error amplifier at lower gains requiring more output
capacitance for stability. At 3.3-V output, a minimum of 4.7 μF is required. For the worst-case condition of 1.23-V
output and 250 mA of load current, a 6.8-μF (or larger) capacitor should be used.
A 1-μF capacitor should be placed from the IN pin to ground if there is more than 10 inches of wire between the
IN pin and the ac filter capacitor or if a battery input is used.
Stray capacitance to the FEEDBACK pin can cause instability. This problem is most likely to appear when using
high-value external resistors to set the output voltage. Adding a 100-pF capacitor between the OUT and
FEEDBACK pins and increasing the output capacitance to 6.8 μF (or greater) will cure the problem.
8.1.2 Minimum Load
When setting the output voltage using an external resistive divider, a minimum current of 1 μA is recommended
through the resistors to provide a minimum load.
It should be noted that a minimum load current is specified in several of the Electrical Characteristics: All Voltage
Options test conditions, so this value must be used to obtain correlation on these tested limits.
8.1.3 Programming the Output Voltage
The regulator may be pin-strapped for 5-V operation using its internal resistive divider by tying the OUTPUT and
SENSE pins together and also tying the FEEDBACK and VTAP pins together.
Alternatively, it may be programmed for any voltage between the 1.23-V reference and the 30-V maximum rating
using an external pair of resistors (see Figure 31). The complete equation for the output voltage is:
where
•
VREF is the 1.23-V reference and IFB is the FEEDBACK pin bias current (−20 nA, typical).
(1)
The minimum recommended load current of 1 μA sets an upper limit of 1.2 MΩ on the value of R2 in cases
where the regulator must work with no load (see Minimum Load). IFB will produce a typical 2% error in VOUT
which can be eliminated at room temperature by trimming R1. For better accuracy, choosing R2 = 100 kΩ will
reduce this error to 0.17% while increasing the resistor program current to 12 μA. Because the typical quiescent
current is 120 μA, this added current is negligible.
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Application Information (continued)
* See Power Supply Recommendations
** Drive with TTL-low to shutdown
Figure 31. Adjustable Regulator
8.1.4 Dropout Voltage
The dropout voltage of the regulator is defined as the minimum input-to-output voltage differential required for the
output voltage to stay within 100 mV of the output voltage measured with a 1-V differential. The dropout voltage
is independent of the programmed output voltage.
8.1.5 Dropout Detection Comparator
This comparator produces a logic low whenever the output falls out of regulation by more than about 5%. This
value results from the comparator built-in offset of 60 mV divided by the 1.23-V reference (see Functional Block
Diagrams). The 5% low trip level remains constant regardless of the programmed output voltage. An out-ofregulation condition can result from low input voltage, current limiting, or thermal limiting.
Figure 32 gives a timing diagram showing the relationship between the output voltage, the ERROR output, and
input voltage as the input voltage is ramped up and down to a regulator programmed for 5-V output. The ERROR
signal becomes low at about 1.3-V input. It goes high at about 5-V input, where the output equals 4.75 V.
Because the dropout voltage is load dependent, the input voltage trip points will vary with load current. The
output voltage trip point does not vary.
The comparator has an open-collector output which requires an external pullup resistor. This resistor may be
connected to the regulator output or some other supply voltage. Using the regulator output prevents an invalid
high on the comparator output that occurs if it is pulled up to an external voltage while the regulator input voltage
is reduced below 1.3 V. In selecting a value for the pullup resistor, note that while the output can sink 400 μA,
this current adds to battery drain. Suggested values range from 100 kΩ to 1 MΩ. This resistor is not required if
the output is unused.
When VIN ≤ 1.3 V, the ERROR pin becomes a high impedance, allowing the error flag voltage to rise to its pullup
voltage. Using VOUT as the pullup voltage (rather than an external 5-V source) will keep the error flag voltage
below 1.2 V (typical) in this condition. The user may wish to divide down the error flag voltage using equal-value
resistors (10 kΩ is suggested) to ensure a low-level logic signal during any fault condition, while still allowing a
valid logic high level during normal operation.
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Application Information (continued)
* In shutdown mode, ERROR will go high if it has been pulled up to an external supply. To avoid this invalid
response, pull up to regulator output.
** Exact value depends on dropout voltage. (See Power Supply Recommendations)
Figure 32. ERROR Output Timing
8.1.6 Output Isolation
The regulator output can be left connected to an active voltage source (such as a battery) with the regulator input
power shut off, as long as the regulator ground pin is connected to ground. If the ground pin is left floating,
damage to the regulator can occur if the output is pulled up by an external voltage source. If the regulator input
power (VIN) is applied, and the SHUTDOWN pin is low, the automatic output discharge circuit will be active, and
any voltage source applied to the output will be discharged to ground.
8.1.7 Reducing Output Noise
In reference applications it may be advantageous to reduce the ac noise present on the output. One method is to
reduce regulator bandwidth by increasing output capacitance. This is relatively inefficient, because large
increases in capacitance are required to get significant improvement.
Noise can be reduced more effectively by a bypass capacitor placed across R1 (see Figure 31). The formula for
selecting the capacitor to be used is:
(2)
This gives a value of about 0.1 μF. When this is used, the output capacitor must be 6.8 μF (or greater) to
maintain stability. The 0.1-μF capacitor reduces the high-frequency gain of the circuit to unity, lowering the output
noise from 260 μV to 80 μV using a 10-Hz to 100-kHz bandwidth. Also, noise is no longer proportional to the
output voltage, so improvements are more pronounced at high output voltages.
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Application Information (continued)
8.1.8 Auxiliary Comparator (LP2953 Only)
The LP2953 contains an auxiliary comparator whose inverting input is connected to the 1.23-V reference. The
auxiliary comparator has an open-collector output whose electrical characteristics are similar to the dropout
detection comparator. The noninverting input and output are brought out for external connections.
8.1.9 SHUTDOWN Input
A logic-level signal will shut off the regulator output when a low (< 1.2 V) is applied to the SHUTDOWN input.
To prevent possible mis-operation, the SHUTDOWN input must be actively terminated. If the input is driven from
open-collector logic, a pullup resistor (20 kΩ to 100 kΩ is recommended) should be connected from the
SHUTDOWN input to the regulator input.
If the SHUTDOWN input is driven from a source that actively pulls high and low (like an op-amp), the pullup
resistor is not required, but may be used.
If the shutdown function is not to be used, the cost of the pullup resistor can be saved by simply tying the
SHUTDOWN input directly to the regulator input.
NOTE
Because the Absolute Maximum Ratings state that the SHUTDOWN input can not go
more than 0.3 V below ground, the reverse battery-input protection feature which protects
the regulator input is sacrificed if the SHUTDOWN input is tied directly to the regulator
input.
If reverse-battery input protection is required in an application, the pullup resistor between the SHUTDOWN input
and the regulator input must be used.
8.2 Typical Applications
8.2.1 Basic 5-V Regulator
Figure 33. Basic 5-V Regulator
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Typical Applications (continued)
8.2.1.1 Design Requirements
For this design example, use the parameters listed in Table 1 as the input parameters.
Table 1. Design Parameters
DESIGN PARAMETER
DESIGN REQUIREMENT
Input voltage
6 V, ±10%, provided by the DC-DC converter switching at 1 MHz
Output voltage
5 V, ±1%
Output current
250 mA (maximum), 1 mA (minimum)
RMS noise, 10 Hz to 100 kHz
1 mV typical
PSRR at 1 kHz
50 dB typical
8.2.1.2 Detailed Design Procedure
At 150-mA loading, the dropout of the LP2952 and LP2953 has 600-mV maximum dropout over temperature —
thus, a 1500-mV headroom is sufficient for operation over both input and output voltage accuracy. The efficiency
of the LP2952 and LP2953 in this configuration is VOUT / VIN = 83.3%. Input and output capacitors are selected in
accordance with the External Capacitors section. Ceramic capacitances of 1 μF for the input and one 2.2-μF
capacitor for the output are selected. With an efficiency of 83.3% and a 250-mA maximum load, the internal
power dissipation is 250 mW, which corresponds to a 19.2°C junction temperature rise for the SOIC package.
With a VIN – VOUT differential of 1 V and a maximum load current of 250 mA the internal junction temperature (TJ)
of the SOIC package will rise 19.2°C above the ambient temperature. With an 85°C maximum ambient
temperature, the junction temperature is at 104.2°C. To minimize noise, a bypass capacitor of 100 pF is selected
between OUT and FEEDBACK pins.
8.2.1.3 Application Curves
Figure 34. Line Transient Response
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Figure 35. Load Transient Response
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8.2.2 5-V Current Limiter with Load Fault Indicator
Figure 36 is the example circuit for 5-V current limiter with load fault indicator, it has the following features:
• Output voltage equals +VIN minimum dropout voltage, which varies with output current. Current limits at a
maximum of 380 mA (typical).
• Select R1 so that the comparator input voltage is 1.23 V at the output voltage which corresponds to the
desired fault current value.
Figure 36. 5-V Current Limiter With Load Fault Indicator
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8.2.3 Low Temperature Coefficient Current Sink
The LP2952 or LP2953 can be used as a low drift current source as Figure 37 shows. By connecting VOUT to
FEEDBACK, VOUT will be regulated at 1.235 V, and current consumption at R is IOUT = 1.23/R.
Figure 37. Low Temperature Coefficient Current Sink
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8.2.4 5-V Regulator With Error Flags for Low Battery and Out of Regulation
Figure 38 is the example circuit for 5-V regulator with error flags for low battery and out of regulation, it has the
following features:
• Connect to logic or microprocessor control inputs.
• LOW BATT flag warns the user that the battery has discharged down to about 5.8 V, giving the user time to
recharge the battery or power down some hardware with high power requirements. The output is still in
regulation at this time.
• OUT OF REGULATION flag indicates when the battery is almost completely discharged, and can be used to
initiate a power-down sequence.
Figure 38. 5-V Regulator With Error Flags for Low Battery and Out of Regulation
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8.2.5 5-V Battery Powered Supply With Backup and Low Battery Flag
Figure 39 is the example circuit for 5-V battery powered supply with backup and low battery flag, it has the
following features:
• The circuit switches to the NI-CAD backup battery when the main battery voltage drops below about 5.6 V
and returns to the main battery when its voltage is recharged to about 6 V.
• The 5-V MAIN output powers circuitry which requires no backup, and the 5-V MEMORY output powers critical
circuitry which cannot be allowed to lose power.
• The BATTERY LOW flag goes low whenever the circuit switches to the NI-CAD backup battery.
Figure 39. 5-V Battery Powered Supply With Backup and Low Battery Flag
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8.2.6 5-V Regulator With Timed Power-On Reset
Figure 40 is the circuit designed to generate a adjustable power on reset signal. Adjusting RT and CT values
causes a certain delay time as Figure 41 shows.
Figure 40. 5-V Regulator With Timed Power-On Reset
* RT = 1 MΩ, CT = 0.1 μF
Figure 41. Timing Diagram for Timed Power-On Reset
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8.2.7 5-V Regulator With Snap-ON and Snap-OFF Features and Hysteresis
Figure 42 is the circuit designed to generate 5-V regulator with snap-ON and snap-OFF features and hysteresis.
The output turns on at VIN = 5.87 V and turns off at VIN = 5.64 V.
* Turns on at VIN = 5.87 V
Turns off at VIN = 5.64 V
(for component values shown)
Figure 42. 5-V Regulator With Snap-ON and Snap-OFF Features and Hysteresis
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8.2.8 5-V Regulator With Error Flags for Low Battery and Out of Regulation With Snap-ON or Snap-OFF
Output
Figure 43 is the circuit as 5-V regulator with error flags for low battery and out of regulation with Snap-ON/SnapOFF output. It has the following features:
• Connect to logic or microprocessor control inputs.
• LOW BATT flag warns the user that the battery has discharged down to about 5.8 V, giving the user time to
recharge the battery or shutdown hardware with high power requirements. The output is still in regulation at
this time.
• OUT OF REGULATION flag goes low if the output goes below about 4.7 V, which could occur from a load
fault.
• OUTPUT has Snap-ON or Snap-OFF feature. Regulator snaps ON at about 5.7-V input, and OFF at about
5.6 V.
Figure 43. 5-V Regulator With Error Flags for Low Battery and Out of Regulation With Snap-ON or SnapOFF Output
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8.2.9 5-V Regulator With Timed Power-On Reset, Snap-ON and Snap-OFF Features, and Hysteresis
Figure 44 is the circuit designed for 5-V regulator with timed power-on reset, Snap-ON and Snap-OFF features,
and hysteresis. Its timing diagram shows as Figure 45.
Figure 44. 5-V Regulator With Timed Power-On Reset, Snap-ON or Snap-OFF Feature, and Hysteresis
td = (0.28), RC = 28 ms for components shown.
Figure 45. Timing Diagram
9 Power Supply Recommendations
The LP2952 and LP2953 is designed to operate from an input voltage supply range between 2.3 V and 30 V.
The input voltage range provides adequate headroom in order for the device to have a regulated output, normally
VIN should be 1 V higher than output voltage to provide a sufficient headroom. 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.
Maximum VIN should never be higher than 30 V. Input voltage beyond 30 V may trigger EOS and cause
permanent damage to the device.
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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 to each other as possible, 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
GROUND
GND
Input
Capacitor
NC
IN
OUT
FEEDBACK
SENSE
VTAP
VIN
Output
Capacitor
VOUT
Ground
Error Pullup
Resistor
Vout
SHUTDOWN
REFERENCE
ERROR
NC
NC
NC
GROUND
GROUND
Figure 46. Layout Schematic
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SNVS095F – MAY 2004 – REVISED MARCH 2015
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10.3 Power Dissipation: Heatsink Requirements (Industrial Temperature Range Devices)
The maximum allowable power dissipation for the LP2952 or LP2953 is limited by the maximum operating
junction temperature (125°C) and the external factors that determine how quickly heat flows away from the part:
the ambient temperature and the junction-to-ambient thermal resistance (RθJA) for the specific application.
The industrial temperature range (−40°C ≤ TJ ≤ 125°C) parts are manufactured in PDIP and surface-mount
packages which contain a copper lead frame that allows heat to be effectively conducted away from the die,
through the ground pins of the IC, and into the copper of the PC board. Details on heatsinking using PC board
copper are covered later.
Figure 47. Power Dissipation vs Ambient Temperature
for RθJA = 95°C/W
To determine if a heatsink is required, the maximum power dissipated by the regulator, P(MAX), must be
calculated. It is important to remember that if the regulator is powered from a transformer connected to the AC
line, the maximum specified AC input voltage must be used (because this produces the maximum DC input
voltage to the regulator). Figure 48 shows the voltages and currents which are present in the circuit. The formula
for calculating the power dissipated in the regulator is also shown in Figure 48:
Figure 48. PTOTAL = (VIN − VOUT) IOUT + (VIN) IG
Current/Voltage Diagram
The next parameter which must be calculated is the maximum allowable temperature rise, TR(MAX). This is
calculated by using the formula:
TR(MAX) = TJ(MAX) − TA(MAX) = RθJA × P(MAX)
where:
•
•
TJ(MAX) is the maximum allowable junction temperature
TA(MAX) is the maximum ambient temperature
(3)
Using the calculated values for TR(MAX) and P(MAX), the required value for junction-to-ambient thermal resistance,
RθJA, can now be found.
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Product Folder Links: LP2952-N LP2952A LP2953 LP2953A
LP2952-N, LP2952A, LP2953, LP2953A
www.ti.com
SNVS095F – MAY 2004 – REVISED MARCH 2015
Power Dissipation: Heatsink Requirements (Industrial Temperature Range Devices) (continued)
The heatsink is made using the PC board copper. The heat is conducted from the die, through the lead frame
(inside the part), and out the pins which are soldered to the PC board. The pins used for heat conduction are
given in Table 2.
Table 2. Heat Conducting Pins
PART
LP2953IN, LP2953AIN
LP2953IN-3.3, LP2953AIN-3.3
PACKAGE
PINS
16-pin PDIP
4, 5, 12, 13
16-pin surface mount (SOIC)
1, 8, 9, 16
LP2952IM, LP2952AIM
LP2952IM-3.3, LP2952AIM-3.3
LP2953IM, LP2953AIM
LP2953IM-3.3, LP2953AIM-3.3
Figure 49 shows copper patterns which may be used to dissipate heat from the LP2952 and LP2953.
* For best results, use L = 2H.
** 14-Pin PDIP is similar, see Table 2 for pins designated for heatsinking.
Figure 49. Copper Heatsink Patterns
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LP2952-N, LP2952A, LP2953, LP2953A
SNVS095F – MAY 2004 – REVISED MARCH 2015
www.ti.com
11 Device and Documentation Support
11.1 Related Links
Table 3 lists quick access links. Categories include technical documents, support and community resources,
tools and software, and quick access to sample or buy.
Table 3. Related Links
PARTS
PRODUCT FOLDER
SAMPLE & BUY
TECHNICAL
DOCUMENTS
TOOLS &
SOFTWARE
SUPPORT &
COMMUNITY
LP2952-N
Click here
Click here
Click here
Click here
Click here
LP2952A
Click here
Click here
Click here
Click here
Click here
LP2953
Click here
Click here
Click here
Click here
Click here
LP2953A
Click here
Click here
Click here
Click here
Click here
11.2 Trademarks
All trademarks are the property of their respective owners.
11.3 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.
11.4 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.
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Product Folder Links: LP2952-N LP2952A LP2953 LP2953A
PACKAGE OPTION ADDENDUM
www.ti.com
30-Sep-2021
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)
(4/5)
(6)
LP2952AIM
NRND
SOIC
D
16
48
Non-RoHS
& Green
Call TI
Level-1-235C-UNLIM
-40 to 125
LP2952AIM
LP2952AIM/NOPB
ACTIVE
SOIC
D
16
48
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
LP2952AIM
LP2952AIMX/NOPB
ACTIVE
SOIC
D
16
2500
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
LP2952AIM
LP2952IM
NRND
SOIC
D
16
48
Non-RoHS
& Green
Call TI
Level-1-235C-UNLIM
-40 to 125
LP2952IM
LP2952IM/NOPB
ACTIVE
SOIC
D
16
48
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
LP2952IM
LP2952IMX/NOPB
ACTIVE
SOIC
D
16
2500
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
LP2952IM
LP2953AIM/NOPB
ACTIVE
SOIC
D
16
48
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
LP2953AIM
LP2953AIMX/NOPB
ACTIVE
SOIC
D
16
2500
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
LP2953AIM
LP2953IM/NOPB
ACTIVE
SOIC
D
16
48
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
LP2953IM
LP2953IMX/NOPB
ACTIVE
SOIC
D
16
2500
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
LP2953IM
(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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