LP2954AISX [TI]
LP2954/LP2954A 5V and Adjustable Micropower Low-Dropout Voltage Regulators; LP2954 / LP2954A 5V和可调微功率低压差稳压器
| 型号： | LP2954AISX |
| 厂家： | 
TEXAS INSTRUMENTS |
| 描述： | LP2954/LP2954A 5V and Adjustable Micropower Low-Dropout Voltage Regulators |
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LP2954, LP2954A
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SNVS096D –JUNE 1999–REVISED MARCH 2013
LP2954/LP2954A 5V and Adjustable Micropower Low-Dropout Voltage Regulators
Check for Samples: LP2954, LP2954A
1
FEATURES
DESCRIPTION
The LP2954 is a 5V micropower voltage regulator
with very low quiescent current (90 μA typical at 1 mA
load) and very low dropout voltage (typically 60 mV at
light loads and 470 mV at 250 mA load current).
2
•
5V Output within 1.2% Over Temperature
(A Grade)
•
Adjustable 1.23 to 29V Output Voltage
Available (LP2954IM and LP2954AIM)
The quiescent current increases only slightly at
dropout (120 μA typical), which prolongs battery life.
•
•
•
•
•
•
•
•
Ensured 250 mA Output Current
Extremely Low Quiescent Current
Low Dropout Voltage
The LP2954 with a fixed 5V output is available in the
three-lead TO-220 and DDPAK/TO-263 packages.
The adjustable LP2954 is provided in an 8-lead
surface mount, small outline package. The adjustable
version also provides a resistor network which can be
pin strapped to set the output to 5V.
Reverse Battery Protection
Extremely Tight Line and Load Regulation
Very Low Temperature Coefficient
Current and Thermal Limiting
Reverse battery protection is provided.
Pin Compatible with LM2940 and LM340
(5V Version Only)
The tight line and load regulation (0.04% typical), as
well as very low output temperature coefficient make
the LP2954 well suited for use as a low-power
voltage reference.
•
Adjustable Version Adds Error Flag to Warn of
Output Drop and a Logic-Controlled Shutdown
Output accuracy is ensured at both room temperature
and over the entire operating temperature range.
APPLICATIONS
•
•
High-Efficiency Linear Regulator
Low Dropout Battery-Powered Regulator
Package Outline and Ordering Information
Figure 1. TO-220 3–Lead Plastic Package (Front
View)
Figure 2. SO-8 Small Outline Surface Mount (Top
View)
Figure 3. TO-263 3-Lead Plastic Surface-Mount
Package (Top View)
Figure 4. TO-263 3-Lead Plastic Surface-Mount
Package (Side View)
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.
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
All trademarks are the property of their respective owners.
2
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 1999–2013, Texas Instruments Incorporated
LP2954, LP2954A
SNVS096D –JUNE 1999–REVISED MARCH 2013
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Absolute Maximum Ratings(1)(2)
Operating Junction Temperature Range
Storage Temperature Range
Lead Temperature (Soldering, 5 seconds)
Power Dissipation(3)
LP2954AI/LP2954I
−40°C to +125°C
−65°C to +150°C
260°C
Internally Limited
−20V to +30V
2 kV
Input Supply Voltage
ESD Rating(4)
(1) 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.
(2) If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/Distributors for availability and
specifications.
(3) The maximum allowable power dissipation is a function of the maximum junction temperature, TJ (MAX), the junction-to-ambient thermal
resistance, θJ-A, and the ambient temperature, TA. The maximum allowable power dissipation at any ambient temperature is calculated
using:
. Exceeding the maximum allowable power dissipation will result in excessive die temperature, and the regulator
will go into thermal shutdown. The junction-to-ambient thermal resistance of the TO-220 (without heatsink) is 60°C/W, 73°C/W for the
DDPAK/TO-263, and 160°C/W for the SOIC-8. If the DDPAK/TO-263 package is used, the thermal resistance can be reduced by
increasing the P.C. board copper area thermally connected to the package: Using 0.5 square inches of copper area, θJA is 50°C/W; with
1 square inch of copper area, θJA is 37°C/W; and with 1.6 or more square inches of copper area, θJA is 32°C/W. The junction-to-case
thermal resistance is 3°C/W. If an external heatsink is used, the effective junction-to-ambient thermal resistance is the sum of the
junction-to-case resistance (3°C/W), the specified thermal resistance of the heatsink selected, and the thermal resistance of the interface
between the heatsink and the LP2954. Some typical values are listed for interface materials used with TO-220:
(4) Human body model, 200pF discharged through 1.5kΩ.
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Electrical Characteristics
Limits in standard typeface are for TJ = 25°C, bold typeface applies over the −40°C to +125°C temperature range. Limits
are specified by production testing or correlation techniques using standard Statistical Quality Control (SQC) methods. Unless
otherwise noted: VIN = 6V, IL = 1 mA, CL = 2.2 μF.
2954AI
2954I
Symbol
VO
Parameter
Conditions
Typical
Units
Min
Max
5.025
5.060
5.070
Min
Max
5.050
5.100
5.120
5.0
4.975
4.940
4.930
4.950
4.900
4.880
Output Voltage(1)
V
1 mA ≤ IL ≤ 250 mA
See(2)
5.0
20
Output Voltage Temp.
Coefficient(1)
100
150
ppm/°C
VIN = 6V to 30V
0.03
0.10
0.20
Line Regulation
Load Regulation
%
%
0.20
0.40
IL = 1 to 250 mA
IL = 0.1 to 1 mA(3)
0.16
0.20
100
150
300
420
400
520
600
800
150
180
2
0.20
0.30
100
150
300
420
400
520
600
800
150
180
2
0.04
60
VIN–VO
IL = 1 mA
IL = 50 mA
IL = 100 mA
IL = 250 mA
IL = 1 mA
240
310
470
90
Dropout Voltage(4)
mV
IGND
μA
IL = 50 mA
IL = 100 mA
IL = 250 mA
VIN = 4.5V
VOUT = 0V
1.1
4.5
21
2.5
6
2.5
6
Ground Pin Current(5)
mA
8
8
28
28
33
33
IGND
170
210
500
530
170
210
500
530
Ground Pin Current at
Dropout(5)
μA
mA
120
380
ILIMIT
Current Limit
Thermal Regulation
See(6)
0.05
0.2
0.2
%/W
en
CL = 2.2 μF
CL = 33 μF
CL=33μF(7)
400
260
80
Output Noise Voltage
(10 Hz to 100 kHz)
IL = 100 mA
μV RMS
(1) 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.
(2) Output voltage temperature coefficient is defined as the worst case voltage change divided by the total temperature range.
(3) Regulation is measured at constant junction temperature using low duty cycle pulse testing. Parts are tested separately for load
regulation in the load ranges 0.1 mA–1 mA and 1 mA–250 mA. Changes in output voltage due to heating effects are covered by the
thermal regulation specification.
(4) Dropout voltage is defined as the input to output differential at which the output voltage drops 100 mV below the value measured with a
1V differential.
(5) Ground pin current is the regulator quiescent current. The total current drawn from the source is the sum of the load current plus the
ground pin current.
(6) Thermal regulation is defined as the change in output voltage at a time T after a change in power dissipation is applied, excluding load
or line regulation effects. Specifications are for 200 mA load pulse at VIN = 20V (3W pulse) for T = 10 ms.
(7) Connect a 0.1μF capacitor from the output to the feedback pin.
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Electrical Characteristics (continued)
Limits in standard typeface are for TJ = 25°C, bold typeface applies over the −40°C to +125°C temperature range. Limits
are specified by production testing or correlation techniques using standard Statistical Quality Control (SQC) methods. Unless
otherwise noted: VIN = 6V, IL = 1 mA, CL = 2.2 μF.
2954AI
2954I
Symbol
Parameter
Conditions
Typical
Units
Min
Max
Min
Max
Additional Specifications for the Adjustable Device (LP2954AIM and LP2954IM)
VREF
See(8)
1.230
0.03
1.215
1.205
1.245
1.255
1.205
1.190
1.255
1.270
Reference Voltage
V
%
%
ΔVREF
VREF
/
VIN=2.5V to
VO(NOM)+1V
0.1
0.2
Reference Voltage
Line Regulation
VIN=2.5V to
0.2
0.4
VO(NOM)+1V to 30V(9)
ΔVREF/ΔT Reference Voltage
Temperature
See(2)
20
ppm/°C
Coefficient
IB(FB)
IGND
Feedback Pin Bias
Current
20
40
60
40
60
nA
μA
Ground Pin Current at
Shutdown(5)
VSHUTDOWN≤1.1V
105
140
140
IO(SINK)
Output "OFF" Pulldown See(10)
Current
30
20
30
20
mA
Dropout Detection Comparator
IOH
Output "HIGH"
Leakage Current
VOH=30V
0.01
150
−60
−85
15
1
2
1
2
μA
mV
mV
VOL
VIN=VO(NOM)−0.5V
IO(COMP)=400μA
250
400
250
400
Output "LOW" Voltage
VTHR(MAX) Upper Threshold
Voltage
See(11)
See(12)
See(12)
−80
−95
−35
−25
−80
−95
−35
−25
VTHR(MIN) Lower Threshold
Voltage
−110
−160
−55
−40
−110
−160
−55
−40
mV
mV
HYST
Hysteresis
Shutdown Input
VOS
(Referred to VREF
)
±3
−7.5
−10
7.5
10
−7.5
−10
7.5
10
Input Offset Voltage
mV
mV
nA
HYST
IB
Hysteresis
6
VIN(S/D)=0V to 5V
10
−30
−50
30
50
−30
−50
30
50
Input Bias Current
(8)
VREF≤VOUT≤(VIN−1V), 2.3V≤VIN≤30V, 100μA≤IL≤250mA.
(9) Two seperate tests are performed, one covering VIN=2.5V to VO(NOM)+1V and the other test for VIN=2.5V to VO(NOM)+1V to 30V.
(10) VSHUTDOWN≤1.1V, VOUT=VO(NOM).
(11) Comparator thresholds are expressed in terms of a voltage differential at the Feedback terminal below the nominal reference voltage
measured at VIN=VO(NOM)+1V. To express these thresholds in terms of output voltage change, multiply by the Error amplifier gain,
which is VOUT/VREF=(R1+R2)/R2.
(12) Comparator thresholds are expressed in terms of a voltage differential at the Feedback terminal below the nominal reference voltage
measured at VIN=VO(NOM)+1V. To express these thresholds in terms of output voltage change, multiply by the Error amplifier gain,
which is VOUT/VREF=(R1+R2)/R2.
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Table 1. Typical Values of Case-to-Heatsink
Thermal Resistance (°C/W) (Data from AAVID Eng.)
Silicone grease
Dry interface
1.0
1.3
1.4
Mica with grease
Table 2. Typical Values of Case-to-Heatsink
Thermal Resistance (°C/W) (Data from Thermalloy)
Thermasil III
1.3
1.5
2.2
Thermasil II
Thermalfilm (0.002) with grease
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Typical Performance Characteristics
Quiescent Current
Quiescent Current
Figure 5.
Figure 6.
Ground Pin Current vs Load
Ground Pin Current
Figure 7.
Figure 8.
Ground Pin Current
Output Noise Voltage
Figure 9.
Figure 10.
6
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Typical Performance Characteristics (continued)
Ripple Rejection
Ripple Rejection
Figure 11.
Figure 12.
Ripple Rejection
Line Transient Response
Figure 13.
Figure 14.
Line Transient Response
Output Impedance
Figure 15.
Figure 16.
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Typical Performance Characteristics (continued)
Load Transient Response
Load Transient Response
Figure 17.
Figure 18.
Dropout Characteristics
Thermal Response
Figure 19.
Figure 20.
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Typical Performance Characteristics (continued)
Short-Circuit Output
Current and Maximum
Output Current
Maximum Power Dissipation
(DDPAK/TO-263)(1)
Figure 21.
Figure 22.
(1) The maximum allowable power dissipation is a function of the maximum junction temperature, TJ (MAX), the junction-to-ambient thermal
resistance, θJ-A, and the ambient temperature, TA. The maximum allowable power dissipation at any ambient temperature is calculated
using:
. Exceeding the maximum allowable power dissipation will result in excessive die temperature, and the regulator
will go into thermal shutdown. The junction-to-ambient thermal resistance of the TO-220 (without heatsink) is 60°C/W, 73°C/W for the
DDPAK/TO-263, and 160°C/W for the SOIC-8. If the DDPAK/TO-263 package is used, the thermal resistance can be reduced by
increasing the P.C. board copper area thermally connected to the package: Using 0.5 square inches of copper area, θJA is 50°C/W; with
1 square inch of copper area, θJA is 37°C/W; and with 1.6 or more square inches of copper area, θJA is 32°C/W. The junction-to-case
thermal resistance is 3°C/W. If an external heatsink is used, the effective junction-to-ambient thermal resistance is the sum of the
junction-to-case resistance (3°C/W), the specified thermal resistance of the heatsink selected, and the thermal resistance of the interface
between the heatsink and the LP2954. Some typical values are listed for interface materials used with TO-220:
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APPLICATION HINTS
EXTERNAL CAPACITORS
A 2.2 μF (or greater) capacitor is required between the output pin and the ground to assure stability (refer to
Figure 23). Without this capacitor, the part may oscillate. Most types of tantalum or aluminum electrolytics will
work here. Film types will work, but are more expensive. Many aluminum electrolytics contain electrolytes which
freeze at −30°C, which requires the use of solid tantalums below −25°C. The important parameters of the
capacitor are an ESR of about 5Ω 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.
A 1 μF capacitor should be placed from the input pin to ground if there is more than 10 inches of wire between
the input and the AC filter capacitor or if a battery input is used.
Programming the output for voltages below 5V runs the error amplifier at lower gains requiring more output
capacitance for stability. At 3.3V output, a minimum of 4.7 μF is required. For the worst case condition of 1.23V
output and 250 mA of load current, a 6.8 μF (or larger) capacitor should be used.
Stray capacitance to the Feedback terminal 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 Output and
Feedback pins and increasing the output capacitance to 6.8 μF (or greater) will cure the problem.
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 characteristic test
conditions, so this value must be used to obtain correlation on these tested limits. The part is parametrically
tested down to 100 μA, but is functional with no load.
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 1V differential. The dropout voltages
for various values of load current are listed under Electrical Characteristics.
If the regulator is powered from a rectified AC source with a capacitive filter, the minimum AC line voltage and
maximum load current must be used to calculate the minimum voltage at the input of the regulator. The minimum
input voltage, including AC ripple on the filter capacitor, must not drop below the voltage required to keep the
LP2954 in regulation. It is also advisable to verify operating at minimum operating ambient temperature, since
the increasing ESR of the filter capacitor makes this a worst-case test for dropout voltage due to increased ripple
amplitude.
HEATSINK REQUIREMENTS
A heatsink may be required with the LP2954 depending on the maximum power dissipation and maximum
ambient temperature of the application. Under all possible operating conditions, the junction temperature must be
within the range specified under Absolute Maximum Ratings.
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 (since this produces the maximum DC input
voltage to the regulator). Figure 23 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 23.
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*See EXTERNAL CAPACITORS
PTotal = (VIN −5) IL+ (VIN) IG
Figure 23. Basic 5V Regulator Circuit
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)
where
•
•
TJ(max) is the maximum allowable junction temperature
TA(max) is the maximum ambient temperature
(1)
Using the calculated values for TR(max) and P(max), the required value for junction-to-ambient thermal
resistance, θ(J-A), can now be found:
θ(J-A) = TR(max)/P(max)
(2)
If the calculated value is 60° C/W or higher , the regulator may be operated without an external heatsink. If the
calculated value is below 60° C/W, an external heatsink is required. The required thermal resistance for this
heatsink can be calculated using the formula:
θ(H-A) = θ(J-A) − θ(J-C) − θ(C-H)
where
•
•
θ(J-C) is the junction-to-case thermal resistance, which is specified as 3° C/W maximum for the LP2954
θ(C-H) is the case-to-heatsink thermal resistance, which is dependent on the interfacing material (if used). For details
and typical values(2)
•
θ(H-A) is the heatsink-to-ambient thermal resistance. It is this specification (listed on the heatsink manufacturers data
sheet) which defines the effectiveness of the heatsink. The heatsink selected must have a thermal resistance which
is equal to or lower than the value of θ(H-A) calculated from the above listed formula
(3)
PROGRAMMING THE OUTPUT VOLTAGE
The regulator may be pin-strapped for 5V operation using its internal resistive divider by tying the Output and
Sense pins together and also tying the Feedback and 5V Tap pins together.
Alternatively, it may be programmed for any voltage between the 1.23V reference and the 30V maximum rating
using an external pair of resistors (see Figure 24). The complete equation for the output voltage is:
(4)
(2) The maximum allowable power dissipation is a function of the maximum junction temperature, TJ (MAX), the junction-to-ambient thermal
resistance, θJ-A, and the ambient temperature, TA. The maximum allowable power dissipation at any ambient temperature is calculated
using:
. Exceeding the maximum allowable power dissipation will result in excessive die temperature, and the regulator
will go into thermal shutdown. The junction-to-ambient thermal resistance of the TO-220 (without heatsink) is 60°C/W, 73°C/W for the
DDPAK/TO-263, and 160°C/W for the SOIC-8. If the DDPAK/TO-263 package is used, the thermal resistance can be reduced by
increasing the P.C. board copper area thermally connected to the package: Using 0.5 square inches of copper area, θJA is 50°C/W; with
1 square inch of copper area, θJA is 37°C/W; and with 1.6 or more square inches of copper area, θJA is 32°C/W. The junction-to-case
thermal resistance is 3°C/W. If an external heatsink is used, the effective junction-to-ambient thermal resistance is the sum of the
junction-to-case resistance (3°C/W), the specified thermal resistance of the heatsink selected, and the thermal resistance of the interface
between the heatsink and the LP2954. Some typical values are listed for interface materials used with TO-220:
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where VREF is the 1.23V reference and IFB is the Feedback pin bias current (−20 nA typical). 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. Since the typical quiescent current is 120 μA,
this added current is negligible.
* See Application Hints
** Drive with TTL-low to shut down
Figure 24. Adjustable Regulator
DROPOUT DETECTION COMPARATOR
This comparator produces a logic “LOW” whenever the output falls out of regulation by more than about 5%. This
figure results from the comparator's built-in offset of 60 mV divided by the 1.23V reference. The 5% low trip level
remains constant regardless of the programmed output voltage. An out-of-regulation condition can result from
low input voltage, current limiting, or thermal limiting.
Figure 25 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 5V output. The ERROR
signal becomes low at about 1.3V input. It goes high at about 5V input, where the output equals 4.75V. Since 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 pull-up 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 which occurs if it is pulled up to an external voltage while the regulator input
voltage is reduced below 1.3V. In selecting a value for the pull-up 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 ≤ 1.3V, the error flag pin becomes a high impedance, allowing the error flag voltage to rise to its pull-
up voltage. Using VOUT as the pull-up voltage (rather than an external 5V source) will keep the error flag voltage
below 1.2V (typical) in this condition. The user may wish to divide down the error flag voltage using equal-value
resistors (10 kΩ suggested) to ensure a low-level logic signal during any fault condition, while still allowing a valid
high logic level during normal operation.
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* 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 Application Hints)
Figure 25. ERROR Output Timing
OUTPUT ISOLATION
The regulator output can be left connected to an active voltage source (such as a battery) with the regulator input
power turned 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.
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, since large
increases in capacitance are required to get significant improvement.
Noise can be reduced more effectively by a bypass capacitor placed across R1 (refer to Figure 24). The formula
for selecting the capacitor to be used is:
(5)
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.
SHUTDOWN INPUT
A logic-level signal will shut off the regulator output when a “LOW” (<1.2V) 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 pull-up resistor (20 kΩ to 100 kΩ 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 pull-up resistor
is not required, but may be used.
If the shutdown function is not to be used, the cost of the pull-up resistor can be saved by simply tying the
Shutdown input directly to the regulator input.
IMPORTANT: Since the Absolute Maximum Ratings state that the Shutdown input can not go more than 0.3V
below ground, the reverse-battery protection feature which protects the regulator input is sacrificed if the
Shutdown input is tied directly to the regulator input.
If reverse-battery protection is required in an application, the pull-up resistor between the Shutdown input and the
regulator input must be used.
Copyright © 1999–2013, Texas Instruments Incorporated
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Product Folder Links: LP2954 LP2954A
LP2954, LP2954A
SNVS096D –JUNE 1999–REVISED MARCH 2013
www.ti.com
Typical Applications
Figure 26. Typical Application Circuit
Figure 27. 5V Regulator
*Output voltage equals +VIN minus dropout voltage, which varies with output current. Current limits at 380 mA
(typical).
Figure 28. 5V Current Limiter
14
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Copyright © 1999–2013, Texas Instruments Incorporated
Product Folder Links: LP2954 LP2954A
LP2954, LP2954A
www.ti.com
SNVS096D –JUNE 1999–REVISED MARCH 2013
Schematic Diagram
Copyright © 1999–2013, Texas Instruments Incorporated
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15
Product Folder Links: LP2954 LP2954A
LP2954, LP2954A
SNVS096D –JUNE 1999–REVISED MARCH 2013
www.ti.com
REVISION HISTORY
Changes from Revision C (March 2013) to Revision D
Page
•
Changed layout of National Data Sheet to TI format .......................................................................................................... 15
16
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Copyright © 1999–2013, Texas Instruments Incorporated
Product Folder Links: LP2954 LP2954A
PACKAGE OPTION ADDENDUM
www.ti.com
1-Nov-2013
PACKAGING INFORMATION
Orderable Device
LP2954AIM
Status Package Type Package Pins Package
Eco Plan
Lead/Ball Finish
MSL Peak Temp
Op Temp (°C)
-40 to 125
-40 to 125
-40 to 125
-40 to 125
-40 to 125
-40 to 125
-40 to 125
-40 to 125
-40 to 125
-40 to 125
-40 to 125
-40 to 125
-40 to 125
-40 to 125
-40 to 125
Device Marking
Samples
Drawing
Qty
(1)
(2)
(6)
(3)
(4/5)
NRND
SOIC
SOIC
SOIC
D
8
8
8
3
3
3
3
3
8
8
8
3
3
3
3
95
TBD
Call TI
SN | CU SN
CU SN
Call TI
Call TI
LP295
4AIM
LP2954AIM/NOPB
LP2954AIMX/NOPB
LP2954AIS
ACTIVE
ACTIVE
NRND
D
D
95
2500
45
Green (RoHS
& no Sb/Br)
Level-1-260C-UNLIM
Level-1-260C-UNLIM
Call TI
LP295
4AIM
Green (RoHS
& no Sb/Br)
LP295
4AIM
DDPAK/
TO-263
KTT
KTT
KTT
KTT
NDE
D
TBD
LP2954AIS
LP2954AIS
LP2954AIS
LP2954AIS
LP2954AIT
LP2954AIS/NOPB
LP2954AISX
ACTIVE
NRND
DDPAK/
TO-263
45
Pb-Free (RoHS
Exempt)
CU SN
Call TI
Level-3-245C-168 HR
Call TI
DDPAK/
TO-263
500
500
45
TBD
LP2954AISX/NOPB
LP2954AIT/NOPB
LP2954IM
ACTIVE
ACTIVE
NRND
DDPAK/
TO-263
Pb-Free (RoHS
Exempt)
CU SN
CU SN
Call TI
Level-3-245C-168 HR
Level-1-NA-UNLIM
Call TI
TO-220
SOIC
SOIC
SOIC
Green (RoHS
& no Sb/Br)
95
TBD
LP29
54IM
LP2954IM/NOPB
LP2954IMX/NOPB
LP2954IS/NOPB
LP2954ISX
ACTIVE
ACTIVE
ACTIVE
NRND
D
95
Green (RoHS
& no Sb/Br)
CU SN
CU SN
CU SN
Call TI
Level-1-260C-UNLIM
Level-1-260C-UNLIM
Level-3-245C-168 HR
Call TI
LP29
54IM
D
2500
45
Green (RoHS
& no Sb/Br)
LP29
54IM
DDPAK/
TO-263
KTT
KTT
KTT
NDE
Pb-Free (RoHS
Exempt)
LP2954IS
LP2954IS
LP2954IS
LP2954IT
DDPAK/
TO-263
500
500
45
TBD
LP2954ISX/NOPB
LP2954IT/NOPB
ACTIVE
ACTIVE
DDPAK/
TO-263
Pb-Free (RoHS
Exempt)
CU SN
CU SN
Level-3-245C-168 HR
Level-1-NA-UNLIM
TO-220
Green (RoHS
& no Sb/Br)
(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.
Addendum-Page 1
PACKAGE OPTION ADDENDUM
www.ti.com
1-Nov-2013
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6) Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish
value exceeds the maximum column width.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
23-Sep-2013
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
B0
K0
P1
W
Pin1
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant
(mm) W1 (mm)
LP2954AIMX/NOPB
LP2954AISX
SOIC
D
8
3
2500
500
330.0
330.0
12.4
24.4
6.5
5.4
2.0
5.0
8.0
12.0
24.0
Q1
Q2
DDPAK/
TO-263
KTT
10.75 14.85
16.0
LP2954AISX/NOPB
DDPAK/
TO-263
KTT
3
500
330.0
24.4
10.75 14.85
5.0
16.0
24.0
Q2
LP2954IMX/NOPB
LP2954ISX
SOIC
D
8
3
2500
500
330.0
330.0
12.4
24.4
6.5
5.4
2.0
5.0
8.0
12.0
24.0
Q1
Q2
DDPAK/
TO-263
KTT
10.75 14.85
16.0
LP2954ISX/NOPB
DDPAK/
TO-263
KTT
3
500
330.0
24.4
10.75 14.85
5.0
16.0
24.0
Q2
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
23-Sep-2013
*All dimensions are nominal
Device
Package Type Package Drawing Pins
SPQ
Length (mm) Width (mm) Height (mm)
LP2954AIMX/NOPB
LP2954AISX
SOIC
D
8
3
3
8
3
3
2500
500
367.0
367.0
367.0
367.0
367.0
367.0
367.0
367.0
367.0
367.0
367.0
367.0
35.0
45.0
45.0
35.0
45.0
45.0
DDPAK/TO-263
DDPAK/TO-263
SOIC
KTT
KTT
D
LP2954AISX/NOPB
LP2954IMX/NOPB
LP2954ISX
500
2500
500
DDPAK/TO-263
DDPAK/TO-263
KTT
KTT
LP2954ISX/NOPB
500
Pack Materials-Page 2
MECHANICAL DATA
NDE0003B
www.ti.com
MECHANICAL DATA
KTT0003B
TS3B (Rev F)
BOTTOM SIDE OF PACKAGE
www.ti.com
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TI warrants performance of its components to the specifications applicable at the time of sale, in accordance with the warranty in TI’s terms
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