TI LP2953QML-SP Lp2953qml adjustable micropower low-dropout voltage regulator Datasheet

LP2953QML, LP2953QML-SP
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LP2953QML Adjustable Micropower Low-Dropout Voltage Regulators
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FEATURES
DESCRIPTION
•
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•
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The LP2953A is a micropower voltage regulator with
very low quiescent current (130 μA typical at 1 mA
load) and very low dropout voltage (typ. 60 mV at
light load and 470 mV at 250 mA load current). It is
ideally
suited
for
battery-powered
systems.
Furthermore, the quiescent current increases only
slightly at dropout, which prolongs battery life.
1
2
Output Voltage Adjusts from 1.23V to 29V
Ensured 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 Protection
50 mA (Typical) Output Pulldown Crowbar
Auxiliary Comparator Included with CMOS/TTL
Compatible Output Levels. Can be used for
Fault Detection, Low Input Line Detection, etc.
APPLICATIONS
•
•
•
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High-Efficiency Linear Regulator
Regulator with Under-Voltage Shutdown
Low Dropout Battery-Powered Regulator
Snap-ON/Snap-OFF Regulator
The LP2953A retains all the desirable characteristics
of the LP2951, but offers increased output current,
additional features, and an improved shutdown
function.
The internal crowbar 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 protection is provided.
The internal voltage reference is made available for
external use, providing a low-T.C. reference with very
good line and load regulation.
Connection Diagram
Note: Pins 1, 8, 9, 16 must be shorted together on customer PC board application
Figure 1. 16-Pin CFP Package
1
2
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.
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.
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Schematic Diagram
2
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Block Diagram
Figure 2. LP2953
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.
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Absolute Maximum Ratings (1)
Storage Temperature Range
−65°C ≤ TA ≤ +150°C
Operating Temperature Range
−55°C ≤ TA ≤ +125°C
Maximum Junction Temperature
+150°C
Lead Temp. (Soldering, 5 seconds)
Power Dissipation
260°C
(2)
Internally Limited
−20V to +30V
Input Supply Voltage
Feedback Input Voltage (3)
Comparator Input Voltage
−0.3V to +5V
(4)
−0.3V to +30V
Shutdown Input Voltage (4)
−0.3V to +30V
Comparator Output Voltage (4)
−0.3V to +30V
16LD CFP "WG" (device 01) (Still Air)
θJA
Thermal Resistance
16LD CFP "GW" (device 02) (Still Air)
16LD CFP "GW" (device 02) (500LF/Min Air flow)
θJC
Package Weight (Typical)
16LD CFP "WG" (device 01) (500LF/Min Air flow)
16LD CFP "WG" (device 01)
(5)
16LD CFP "GW" (device 02)
(2)
(3)
(4)
(5)
(6)
4
81°C/W
140°C/W
90°C/W
7°C/W
15°C/W
16LD CFP "WG" (device 01)
360mg
16LD CFP "GW" (device 02)
410mg
ESD Rating (6)
(1)
134°C/W
2 KV
Abs. Max Ratings indicate limits beyond which damage to the device may occur. Operating ratings indicate conditions for which the
device is functional, but do not ensure specific performance limits. For ensured specifications and test conditions, see Electrical
Characteristics. The specifications apply only for the test conditions listed. Some performance characteristics may degrade when the
device is not operated under the listed test conditions.
The maximum power dissipation must be derated at elevated temperatures and is dictated by TJmax (maximum junction temperature),
θJA (package junction to ambient thermal resistance), and TA (ambient temperature). The maximum allowable power dissipation at any
temperature is PDmax = (TJmax - TA)/θJA or the number given in the Absolute Maximum Ratings, whichever is lower.
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.
The package material for these devices allows much improved heat transfer over our standard ceramic packages. In order to take full
advantage of this improved heat transfer, heat sinking must be provided between the package base (directly beneath the die), and either
metal traces on, or thermal vias through, the printed circuit board. Without this additional heat sinking, device power dissipation must be
calculated using θJA, rather than θJC, thermal resistance. It must not be assumed that the device leads will provide substantial heat
transfer out the package, since the thermal resistance of the leadframe material is very poor, relative to the material of the package
base. The stated θJC thermal resistance is for the package material only, and does not account for the additional thermal resistance
between the package base and the printed circuit board. The user must determine the value of the additional thermal resistance and
must combine this with the stated value for the package, to calculate the total allowed power dissipation for the device.
Human body model, 1.5 KΩ in series with 100 pF.
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Quality Conformance Inspection
Table 1. Mil-Std-883, Method 5005 - Group A
Subgroup
Description
1
Static tests at
Temp (°C)
+25
2
Static tests at
+125
3
Static tests at
-55
4
Dynamic tests at
+25
5
Dynamic tests at
+125
6
Dynamic tests at
-55
7
Functional tests at
+25
8A
Functional tests at
+125
8B
Functional tests at
-55
9
Switching tests at
+25
10
Switching tests at
+125
11
Switching tests at
-55
12
Settling time at
+25
13
Settling time at
+125
14
Settling time at
-55
LP2953A Electrical Characteristics DC Parameters
The following conditions apply, unless otherwise specified. VI = 6V, IL = 1mA, CL = 2.2µF, VO = 5V
Feedback pin is tied to 5V Tap pin. Output pin is tied to Output Sense Pin.
Parameter
VO
Output Voltage
ΔVO / VO
Output Voltage Line
Regulation
Test Conditions
Notes
1mA ≤ IL ≤ 250mA
VI = 6V to 30V
IL = 1mA to 250mA
ΔVO / VO
Output Voltage Load
Regulation
IL = 0.1mA to 1mA
VI - VO
(1)
IL = 1mA
See (1)
IL = 50mA
See (1)
Dropout Voltage
IL = 100mA
See (1)
IL = 250mA
See (1)
Subgroups
Min
Max
Units
4.975
5.025
V
1
4.94
5.06
V
2, 3
4.93
5.07
V
1, 2, 3
0.1
%
1
0.2
%
2, 3
0.16
%
1
0.2
%
2, 3
0.16
%
1
0.2
%
2, 3
100
mV
1
150
mV
2, 3
300
mV
1
420
mV
2, 3
400
mV
1
520
mV
2, 3
600
mV
1
800
mV
2, 3
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. At very low values of programmed output voltage, the input voltage minimum of 2V (2.3V over temperature) must be
observed.
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LP2953A Electrical Characteristics DC Parameters (continued)
The following conditions apply, unless otherwise specified. VI = 6V, IL = 1mA, CL = 2.2µF, VO = 5V
Feedback pin is tied to 5V Tap pin. Output pin is tied to Output Sense Pin.
Parameter
IGnd
Test Conditions
Notes
IL = 1mA
See (2)
IL = 50mA
See (2)
IL = 100mA
See (2)
IL = 250mA
See (2)
Min
Ground Pin Current
IGnd
Ground Pin Current at
Dropout
IGnd
Ground Pin Current at
Shutdown
ILimit
Current Limit
ΔVO / ΔPD
Thermal Regulation
VRef
Reference Voltage
ΔVRef / VRef
Reference Voltage Line
Regulation
VI = 4.5V, IL = 100µA
See (2)
See (2) (3)
VO = 0V
See (4)
See (5)
IB FB
Feedback Pin Bias
Current
IO
Output "Off" Pulldown
Current
(2)
(3)
(4)
(5)
(6)
6
Sink
170
µA
1
200
µA
2, 3
2.0
mA
1
2.5
mA
2, 3
6.0
mA
1
8.0
mA
2, 3
28
mA
1
2, 3
33
mA
210
µA
1
240
µA
2, 3
140
µA
1
500
mA
1
530
mA
2, 3
1
0.2
%/W
1.245
V
1
1.205
1.255
V
2, 3
0.1
%
1
0.2
%
2, 3
0.1
%
1
0.2
%
2, 3
0.4
%
1
0.6
%
2, 3
40
nA
1
nA
2, 3
VI = 6V to 30V
Reference Voltage Load
Regulation
Units
1.215
VI = 2.5V to 6V
ΔVRef / VRef
IRef = 0 to 200µA
60
See (6)
Subgroups
Max
30
mA
1
20
mA
2, 3
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).
VShutdown ≤ 1.1V, VO = VO(Nom).
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 VI = VO(Nom)+15V (3W pulse) for T = 10 mS.
VRef ≤ VO ≤ (VI − 1V), 2.3V ≤ VI ≤ 30V, 100 μA ≤ IL ≤ 250 mA.
VShutdown ≤ 1.1V, VO = VO(Nom).
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LP2953A Electrical Characteristics Dropout Detection Comparator Parameters
The following conditions apply, unless otherwise specified. VI = 6V, IL = 1mA, CL = 2.2µF, VO = 5V
Feedback pin is tied to 5V Tap pin. Output pin is tied to Output Sense Pin.
Parameter
Test Conditions
IOH
Output "High" Leakage
VOH = 30V
VOL
Output "Low" Voltage
VI = 4V, IO Comp = 400µA
VTh Max
Upper Threshold Voltage
VTh Min
(1)
Notes
Min
See (1)
See (1)
Lower Threshold Voltage
Subgroups
Max
Units
1.0
µA
1
2.0
µA
2, 3
250
mV
1
400
mV
2, 3
-320
-150
mV
1
-380
-130
mV
2
-380
-120
mV
3
-450
-280
mV
1
-640
-180
mV
2
-640
-155
mV
3
Comparator thresholds are expressed in terms of a voltage differential at the Feedback terminal below the nominal VRef measured at VI
= VO(Nom) + 1V. To express these thresholds in terms of output voltage change, multiply by the Error amplifier gain, which is VO/ VRef =
(R1 + R2)/R2 (refer to Figure 31).
LP2953A Electrical Characteristics SHUTDOWN Input Parameters
The following conditions apply, unless otherwise specified. VI = 6V, IL = 1mA, CL = 2.2µF, VO = 5V
Feedback pin is tied to 5V Tap pin. Output pin is tied to Output Sense Pin.
Parameter
VIO
IIB
Input Offset Voltage
Input Bias Current
Test Conditions
Notes
Referred to VRef
VI Comp = 0 to 5V
Min
Max
Units
Subgroups
-7.5
7.5
mV
1
-10
10
mV
2
-12
12
mV
3
-30
30
nA
1
-50
50
nA
2
-75
75
nA
3
LP2953A Electrical Characteristics Auxillary Comparator Parameters
The following conditions apply, unless otherwise specified. VI = 6V, IL = 1mA, CL = 2.2µF, VO = 5V
Feedback pin is tied to 5V Tap pin. Output pin is tied to Output Sense Pin.
Parameter
VIO
IIB
Input Offset Voltage
Input Bias Current
Test Conditions
Notes
Referred to VRef
VI Comp = 0 to 5V
Min
Max
Units
Subgroups
-7.5
7.5
mV
1
-10
10
mV
2
-12
12
mV
3
-30
30
nA
1
-50
50
nA
2
-75
IOH
VOL
Output "High" Leakage
Output "Low" Voltage
VOH = 30V, VI Comp = 1.3V
VI Comp = 1.1V, IO Comp = 400µA
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75
nA
3
1.0
µA
1
2.0
µA
2
2.2
µA
3
250
mV
1
400
mV
2
420
mV
3
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LP2953A Electrical Characteristics DC Drift Parameters
The following conditions apply, unless otherwise specified. VI = 6V, IL = 1mA, CL = 2.2µF, VO = 5V
Feedback pin is tied to 5V Tap pin. Output pin is tied to Output Sense Pin.
Δcalculations performed on QMLV devices at group B , subgroup 5.
Min
Max
Units
Subgroups
IL = 1mA
-12
12
%
1
IL = 50mA
-12
12
%
1
IL = 100mA
-12
12
%
1
IL = 250mA
-12
12
%
1
IL = 1mA, ±5µA or ±10% whichever is
greater
-5.0
5.0
µA
1
IL = 50mA, ±5µA or ±10% whichever is
greater
-5.0
5.0
µA
1
IL = 100mA, ±5µA or ±10% whichever is
greater
-5.0
5.0
µA
1
IL = 250mA, ±5µA or ±10% whichever is
greater
-5.0
5.0
µA
1
Parameter
VI - VO
IGnd
Dropout Voltage
Ground Pin Current
Test Conditions
Notes
IGnd
Ground Pin Current at
Dropout
VI = 4.5V, IL = 100µA,
±5µA or ±10% whichever is greater
-5.0
5.0
µA
1
IGnd
Ground Pin Current at
Shutdown
±5µA or ±10% whichever is greater
-5.0
5.0
µA
1
VIO
Input Offset Voltage
Referred to VRefSHUTDOWN Input
-1.0
1.0
mV
1
Referred to VRef Auxillary Comparator
-1.0
1.0
mV
1
VI Comp = 0 to 5V SHUTDOWN Input
-5.0
5.0
nA
1
VI Comp = 0 to 5V Auxillary Comparator
-5.0
5.0
nA
1
IIB
8
Input Bias Current
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Typical Performance Characteristics
Unless otherwise specified: VI = 6V, IL = 1 mA, CL = 2.2 μF, VSD = 3V, TA = 25°C, VO = 5V.
Quiescent Current
Quiescent Current
Figure 3.
Figure 4.
Ground Pin Current vs Load
Ground Pin Current
Figure 5.
Figure 6.
Ground Pin Current
Output Noise Voltage
Figure 7.
Figure 8.
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Typical Performance Characteristics (continued)
Unless otherwise specified: VI = 6V, IL = 1 mA, CL = 2.2 μF, VSD = 3V, TA = 25°C, VO = 5V.
10
Ripple Rejection
Ripple Rejection
Figure 9.
Figure 10.
Ripple Rejection
Line Transient Response
Figure 11.
Figure 12.
Line Transient Response
Output Impedance
Figure 13.
Figure 14.
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Typical Performance Characteristics (continued)
Unless otherwise specified: VI = 6V, IL = 1 mA, CL = 2.2 μF, VSD = 3V, TA = 25°C, VO = 5V.
Load Transient Response
Load Transient Response
Figure 15.
Figure 16.
Dropout Characteristics
Enable Transient
Figure 17.
Figure 18.
Enable Transient
Short-Circuit Output Current
and Maximum Output Current
Figure 19.
Figure 20.
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Typical Performance Characteristics (continued)
Unless otherwise specified: VI = 6V, IL = 1 mA, CL = 2.2 μF, VSD = 3V, TA = 25°C, VO = 5V.
12
Feedback Bias Current
Feedback Pin Current
Figure 21.
Figure 22.
Error Output
Comparator Sink Current
Figure 23.
Figure 24.
Divider Resistance
Dropout Detection Comparator
Threshold Voltages
Figure 25.
Figure 26.
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Typical Performance Characteristics (continued)
Unless otherwise specified: VI = 6V, IL = 1 mA, CL = 2.2 μF, VSD = 3V, TA = 25°C, VO = 5V.
Thermal Regulation
Minimum Operating Voltage
Figure 27.
Figure 28.
Dropout Voltage
Figure 29.
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APPLICATION HINTS
Ground Pins
For the LP2953 16–Pin Ceramic SOIC, Pins 1, 8, 9, 16 MUST BE SHORTED TOGETHER ON CUSTOMER'S
P.C. BOARD APPLICATION.
Heatsink Requirements
The maximum allowable power dissipation for the LP2953 is limited by the maximum junction temperature
(+150°C) and the two parameters that determine how quickly heat flows away from the die: the ambient
temperature and the junction-to-ambient thermal resistance of the part.
The military parts which are manufactured in ceramic DIP packages contain a KOVAR lead frame (unlike the
industrial parts, which have a copper lead frame). The KOVAR material is necessary to attain the hermetic seal
required in military applications.
The KOVAR lead frame does not conduct heat as well as copper, which means that the PC board copper can
not be used to significantly reduce the overall junction-to-ambient thermal resistance.
The power dissipation calculations are done using a fixed value for θ(J–A), the junction-to-ambient thermal
resistance, of 134°C/W and can not be changed by adding copper foil patterns to the PC board. This leads to an
important fact: The maximum allowable power dissipation in any application using the LP2953 is dependent only
on the ambient temperature:
(1)
External Capacitors
A 2.2 μF (or greater) capacitor is required between the output pin and ground to assure stability when the output
is set to 5V. Without this capacitor, the part will oscillate. Most type 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.
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.
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.
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.
14
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Figure 30. Power Derating Curve for LP2953
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 31). The complete equation for the output voltage is:
(2)
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 VO 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 31. Adjustable Regulator
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 voltage is
independent of the programmed output voltage.
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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 (refer to Block
Diagram). 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 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 pullup 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.
* 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 32. 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 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.
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 31). The formula
for selecting the capacitor to be used is:
(3)
16
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SNVS395C – NOVEMBER 2010 – REVISED APRIL 2013
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.
Auxiliary Comparator
The LP2953 contains an auxiliary comparator whose inverting input is connected to the 1.23V reference. The
auxiliary comparator has an open-collector output whose electrical characteristics are similar to the dropout
detection comparator. The non-inverting input and output are brought out for external connections.
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.
Typical Applications
Figure 33. Basic 5V Regulator
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* Output voltage equals +VIN minum 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 1.23V at the output voltage which corresponds to the desired fault
current value.
Figure 34. 5V Current Limiter with Load Fault Indicator
Figure 35. Low T.C. Current Sink
* Connect to Logic or μP control inputs.
LOW BATT flag warns the user that the battery has discharged down to about 5.8V, 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 36. 5V Regulator with Error Flags for
LOW BATTERY and OUT OF REGULATION
18
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The circuit switches to the NI-CAD backup battery when the main battery voltage drops below about 5.6V, and returns
to the main battery when its voltage is recharged to about 6V.
The 5V MAIN output powers circuitry which requires no backup, and the 5V MEMORY output powers critical circuitry
which can not be allowed to lose power.
* The BATTERY LOW flag goes low whenever the circuit switches to the NI-CAD backup battery.
Figure 37. 5V Battery Powered Supply with Backup and Low Battery Flag
Figure 38. 5V Regulator with Timed Power-On Reset
* RT = 1 MEG, CT = 0.1 μF
Figure 39. Timing Diagram for Timed Power-On Reset
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* Connect to Logic or μP control inputs.
OUTPUT has SNAP-ON/SNAP-OFF feature.
LOW BATT flag warns the user that the battery has discharged down to about 5.8V, giving the user time to recharge
the battery or shut down 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 4.7V, which could occur from a load fault.
OUTPUT has SNAP-ON/SNAP-OFF feature. Regulator snaps ON at about 5.7V input, and OFF at about 5.6V.
Figure 40. 5V Regulator with Error Flags for
LOW BATTERY and OUT OF REGULATION
with SNAP-ON/SNAP-OFF Output
Figure 41. 5V Regulator with Timed Power-On Reset, Snap-On/Snap-Off Feature and Hysteresis
Td = (0.28) RC = 28 ms for components shown.
Figure 42. Timing Diagram
20
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SNVS395C – NOVEMBER 2010 – REVISED APRIL 2013
REVISION HISTORY SECTION
Released
Revision
Section
Changes
11/30/2010
A
New Release, Corporate format
1 MDS data sheet converted into one Corp. data
sheet format. MNLP2953AM-X Rev 1A1 will be
archived.
09/01/2011
B
Ordering Information, Absolute Maximum
Ratings
Ordering Information — entered new 'GW' devices.
Absolute Maximum Ratings — added new Theta JA
and Theta JC numbers. LP2953QML Rev A will be
archived.
09/20/2012
C
Connection Diagrams, Application Notes
Connection Diagrams and Applications Notes :
Added: * Pins 1, 8, 9, 16 MUST BE SHORTED
TOGETHER ON CUSTOMER'S P.C. BOARD
APPLICATION. Rev B will be archived.
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REVISION HISTORY
Changes from Revision B (April 2013) to Revision C
•
22
Page
Changed layout of National Data Sheet to TI format .......................................................................................................... 17
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PACKAGE OPTION ADDENDUM
www.ti.com
22-Apr-2013
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
Lead/Ball Finish
(2)
MSL Peak Temp
Op Temp (°C)
(3)
Top-Side Markings
(4)
5962-9233602QXA
ACTIVE
CFP
NAC
16
42
TBD
Call TI
Call TI
-55 to 125
LP2953AMGW
/883 Q
5962-92336
02QXA ACO
02QXA >T
5962-9233602VXA
ACTIVE
CFP
NAC
16
42
TBD
Call TI
Call TI
-55 to 125
LP2953AMGWQMLV Q
5962-92336
02VXA ACO
02VXA >T
LP2953AMGW-QMLV
ACTIVE
CFP
NAC
16
42
TBD
Call TI
Call TI
-55 to 125
LP2953AMGWQMLV Q
5962-92336
02VXA ACO
02VXA >T
LP2953AMGW/883
ACTIVE
CFP
NAC
16
42
TBD
Call TI
Call TI
-55 to 125
LP2953AMGW
/883 Q
5962-92336
02QXA ACO
02QXA >T
(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)
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)
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
(3)
22-Apr-2013
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4)
Multiple Top-Side Markings will be inside parentheses. Only one Top-Side 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 Top-Side Marking for that device.
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.
OTHER QUALIFIED VERSIONS OF LP2953QML, LP2953QML-SP :
• Military: LP2953QML
• Space: LP2953QML-SP
NOTE: Qualified Version Definitions:
• Military - QML certified for Military and Defense Applications
• Space - Radiation tolerant, ceramic packaging and qualified for use in Space-based application
Addendum-Page 2
MECHANICAL DATA
NAC0016A
WG16A (RevG)
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