NSC LP2956A

LP2956/LP2956A
Dual Micropower Low-Dropout Voltage Regulators
General Description
Features
The LP2956 is a micropower voltage regulator with very low
quiescent current (170 μA typical at light loads) and very low
dropout voltage (typically 60 mV at 1 mA load current and 470
mV at 250 mA load current on the main output).
The LP2956 retains all the desirable characteristics of the
LP2951, but offers increased output current (main output), an
auxiliary LDO adjustable regulated output (75 mA), and additional features.
The auxiliary output is always on (regardless of main output
status), so it can be used to power memory circuits.
Quiescent current increases only slightly at dropout, which
prolongs battery life.
The error flag goes low if the main output voltage drops out
of regulation.
An open-collector auxiliary comparator is included, whose inverting input is tied to the 1.23V reference.
Reverse battery protection is provided.
The parts are available in DIP and surface mount packages.
■
■
■
■
■
■
■
■
■
■
■
Output voltage adjusts from 1.23V to 29V
Guaranteed 250 mA current (main output)
Auxiliary LDO (75 mA) adjustable output
Auxiliary comparator with open-collector output
Shutdown pin for main output
Extremely low quiescent current
Low dropout voltage
Extremely tight line and load regulation
Very low temperature coefficient
Current and thermal limiting
Reverse battery protection
Applications
■ High-efficiency linear regulator
■ Low dropout battery-powered regulator
■ μP system regulator with switchable high-current VCC
Block Diagram
LP2956
1133901
© 2009 National Semiconductor Corporation
11339
11339 Version 8 Revision 4
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Print Date/Time: 2009/12/07 17:53:15
LP2956/LP2956A Dual Micropower Low-Dropout Voltage Regulators
OBSOLETE
December 7, 2009
LP2956/LP2956A
Connection Diagrams
16–Pin DIP
1133902
Order Number LP2956IN or LP2956AIN
See NS Package Number N16A
Order Number LP2956AMJ-QML or 5962-9554701QEA
See NS Package Number J16A
16-Pin Surface Mount
1133903
Order Number LP2956IM or LP2956AIM
See NS Package Number M16A
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If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Storage Temperature Range
Operating Junction
Temperature Range
Lead Temperature
(Soldering, 5 seconds)
Power Dissipation (Note 2)
−65°C to +150°C
−40°C to +125°C
−20V to +30V
−0.3V to +5V
−0.3V to +5V
−0.3V to +30V
−0.3V to +30V
−0.3V to +30V
2 kV
260°C
Internally Limited
Electrical Characteristics
Limits in standard typeface are for TJ = 25°C, and limits in boldface type apply over the full operating temperature range. Limits
are guaranteed by production testing or correlation techniques using standard Statistical Quality Control (SQC) methods. Unless
otherwise specified: VIN = 6V, CL = 2.2 μF (Main Output) and 10 μF (Auxiliary Output), Feedback pin is tied to 5V Tap pin, CIN = 1
μF, VSD = 0V, Main Output pin is tied to Output Sense pin, Auxiliary Output is programmed for 5V. The main regulator output has
a 1 mA load, the auxiliary regulator output has a 100 μA load.
Symbol
Parameter
Conditions
Typical
LP2956AI
LP2956I
Units
Min
Max
Min
Max
4.975
5.025
4.950
5.050
4.940
5.060
4.900
5.100
4.930
5.070
4.880
5.120
MAIN OUTPUT
VO
Output Voltage
5.0
1 mA ≤ IL ≤ 250 mA
5.0
Temperature Coefficient
(Note 5)
20
100
150
ppm/°C
Line Regulation
VIN = 6V to 30V
0.03
0.1
0.2
%
0.2
0.4
0.16
0.20
0.20
0.30
100
100
150
150
300
300
420
420
400
400
520
520
600
600
800
800
500
500
530
530
0.2
0.2
Load Regulation
IL = 1 mA to 250 mA
0.04
IL = 0.1 mA to 1 mA (Note 6)
VIN–VO
Dropout Voltage
IL = 1 mA
60
(Note 7)
IL = 50 mA
ILIMIT
en
V
Current Limit
240
IL = 100 mA
310
IL = 250 mA
470
RL = 1Ω
380
Thermal Regulation
(Note 8)
0.05
Output Noise Voltage
CL = 2.2 μF
400
(10 Hz to 100 KHz)
CL = 33 μF
260
IL = 100 mA
CL = 33 μF (Note 9)
80
VFB
Feedback Pin Voltage
IFB
Feedback Pin Bias
1.23
1.215
1.245
20
Output Leakage
I(SD IN) ≥ 1 μA
(OFF)
In Shutdown
VIN = 30V, VOUT = 0V
3
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mV
mA
%/W
μV RMS
Current
IO
%
Print Date/Time: 2009/12/07 17:53:15
1.205
1.255
V
40
40
nA
60
60
10
10
20
20
μA
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LP2956/LP2956A
Input Supply Voltage
Feedback Input Voltage (Note 3)
Aux. Feedback Input Voltage (Note 3)
Shutdown Input Voltage (Note 3)
Comparator Input Voltage (Note 3,
Note 4)
Comparator Output Voltage (Note 3,
Note 4)
ESD Rating (Note 16)
Absolute Maximum Ratings (Note 1)
LP2956/LP2956A
Symbol
Parameter
Conditions
Typical
LP2956AI
LP2956I
Min
Max
Min
Max
1.22
1.25
1.21
1.26
1.21
1.26
1.20
1.27
Units
AUXILIARY OUTPUT
VFB
IFB
Feedback Pin Voltage
1.23
Feedback Voltage
Temperature Coefficient
20
Feedback Pin Bias
10
ppm/°C
Current
6V ≤ VIN ≤ 30V
Line Regulation
Load Regulation
0.07
IL = 0.1 mA to 1 mA
0.1
IL = 1 mA to 75 mA (Note 10)
VIN–VO
Dropout Voltage
IL = 1 mA
100
IL = 50 mA
400
IL = 75 mA
en
500
Output Noise
CL = 10 μF
300
(10 Hz–100 KHz)
CL = 33 μF (Note 9)
100
V
20
20
30
30
0.3
0.4
0.5
0.6
0.3
0.4
0.6
1.0
200
200
300
300
600
600
700
700
700
700
850
850
nA
%
%
mV
mV
mV
μV RMS
IL = 10 mA
ILIM
Current Limit
VOUT = 0V (Note 13)
Thermal Regulation
80
200
200
250
250
mA
(Note 8)
0.2
0.5
0.5
%/W
VOH = 30V
0.01
1
1
μA
2
2
250
250
400
400
DROPOUT DETECTION COMPARATOR
IOH
VOL
Output “HIGH” Leakage
Output “LOW” Voltage
VIN = 4V
150
IO (COMP) = 400 μA
VTHR
Upper Threshold Voltage
(Note 11)
−240
(max)
VTHR
Lower Threshold Voltage
(Note 11)
−350
Hysteresis
(Note 11)
110
0.03
(min)
HYST
−320
−150
−320
−150
−380
−100
−380
−100
−450
−230
−450
−230
−640
−160
−640
−160
mV
mV
mV
mV
SHUTDOWN INPUT
IIN
Input Current to Disable
Output
(Note 12)
VIH
Shutdown Input High
I(SD IN) ≥ 1 μA
Threshold
VIL
Shutdown Input Low
0.5
0.5
900
900
1200
1200
VO ≥ 4.5V
Threshold
μA
mV
400
400
200
200
mV
AUXILIARY COMPARATOR
VT(high)
Upper Trip Point
VT(low)
Lower Trip Point
HYST
Hysteresis
(Note 14)
1.236
(Note 14)
1.230
1.20
1.28
1.20
1.28
1.19
1.29
1.19
1.29
1.19
1.18
1.27
1.28
1.19
1.18
1.27
1.28
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V
V
mV
Parameter
Conditions
Typical
LP2956AI
Min
IOH
Output “HIGH” Leakage
VOH = 30V
0.01
VIN (COMP) = 1.3V
VOL
Output “LOW” Voltage
VIN (COMP) = 1.1V
150
IO(COMP) = 400 μA
IB
0 ≤ VIN (COMP) ≤ 5V
Input Bias Current
10
Max
LP2956I
Min
Units
Max
1
1
2
2
250
250
400
400
−30
30
−30
30
−50
50
−50
50
μA
mV
nA
GROUND PIN CURRENT
IGND
Ground Pin Current
IL (Main Out) = 1 mA
(Note 15)
IL (Aux. Out) = 0.1 mA
170
IL (Main Out) = 50 mA
1.1
IL (Aux. Out) = 1 mA
IL (Main Out) = 100 mA
3
IL (Aux. Out) = 1 mA
IL (Main Out) = 250 mA
16
IL (Aux. Out) = 1 mA
IL (Main Out) = 1 mA
3
IL (Aux. Out) = 50 mA
IL (Main Out) = 1 mA
6
IL (Aux. Out) = 75 mA
IGND
Ground Pin Current
VIN = 4.5V
at Dropout (Note 15)
IL (Main Out) = 0.1 mA
250
250
280
280
2
2
2.5
2.5
6
6
8
8
28
28
33
33
6
6
8
8
8
8
10
10
325
325
270
350
350
120
180
180
200
200
mA
μA
IL (Aux. Out) = 0.1 mA
IGND
μA
Ground Pin Current
No Load on Either Output
at Shutdown (Note 15)
I(SD IN) ≥ 1 μA
Note 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.
Note 2: The maximum allowable power dissipation is a function of the maximum junction temperature, T J(max), the junction-to-ambient thermal resistance, θ JA, and the ambient temperature, TA. The maximum allowable power dissipation at any ambient temperature is calculated using: P(max) =
.
Exceeding the maximum allowable power dissipation will cause excessive die temperature, and the regulator will go into thermal shutdown. See Application Hints
for additional information on heat sinking and thermal resistance.
Note 3: 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.
Note 4: May exceed the input supply voltage.
Note 5: Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by the total temperature range.
Note 6: Load regulation is measured at constant junction temperature using low duty cycle pulse testing. Two separate tests are performed, one for the range of
100 μA to 1 mA and one for the 1 mA to 250 mA range. Changes in output voltage due to heating effects are covered by the thermal regulation specification.
Note 7: 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.
Note 8: 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 = 20V (3W pulse) for T = 10 ms on the Main regulator output. For the Auxiliary regulator output, specifications are for a 66 mA
load pulse at VIN = 20V (1W pulse) for T = 10 ms.
Note 9: Connect a 0.1 μF capacitor from the output to the feedback pin.
Note 10: Load regulation is measured at constant junction temperature using low duty cycle pulse testing. Two separate tests are performed, one for the range
of 100 μA to 1 mA and one for the 1 mA to 75 mA range. Changes in output voltage due to heating effects are covered by the thermal regulation specification.
Note 11: Dropout dectection comparator thresholds are expressed as changes in a 5V output. To express the threshold voltages in terms of a differential at the
Feedback terminal, divide by the error amplifier gain = VOUT/V REF.
Note 12: The shutdown input equivalent circuit is the base of a grounded-emitter NPN transistor in series with a current-limiting resistor. Pulling the shutdown
input high turns off the main regulator. For more details, see Application Hints.
Note 13: The auxiliary regulator output has foldback limiting, which means the output current reduces with output voltage. The tested limit is for VOUT = 0V, so
the output current will be higher at higher output voltages.
Note 14: This test is performed with the auxiliary comparator output sinking 400 μA of current. At the upper trip point, the comparator output must be ≥2.4V. At
the low trip point, the comparator output must be ≤ 0.4V.
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LP2956/LP2956A
Symbol
LP2956/LP2956A
Note 15: 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 dividers (if used).
Note 16: All pins are rated for 2 kV, except for the auxiliary feedback pin which is rated for 1.2 kV (human body model, 100 pF discharged through 1.5 kΩ).
Typical Performance Characteristics
Unless otherwise specified: VIN = 6V, CL = 2.2 μF (Main Output)
and 10 μF (Auxiliary Output), Feedback is tied to 5V Tap pin, CIN = 1 μF, VSD = 0V, Main Output pin is tied to Output Sense pin,
Auxiliary Output is programmed for 5V. The main regulator output has a 1 mA load, the auxiliary output has a 100 μA load.
Ground Pin Current
Ground Pin Current
1133918
1133919
Ground Pin Current
Ground Pin Current
1133920
1133921
Ground Pin Current
Ground Pin Current
1133923
1133922
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11339 Version 8 Revision 4
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LP2956/LP2956A
Ground Pin Current
vs Main Load
Dropout Characteristics
(Main Regulator)
1133925
1133924
Dropout Voltage vs
Temperature (Main Regulator)
Current Limit vs Regulator
(Main Regulator)
1133926
1133927
Enable Transient
(Main Regulator)
Enable Transient
(Main Regulator)
1133929
1133928
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LP2956/LP2956A
Load Transient Response
(Main Regulator)
Load Transient Response
(Main Regulator)
1133931
1133930
Line Transient Response
(Main Regulator)
Line Transient Response
(Main Regulator)
1133932
1133933
Ripple Rejection
(Main Regulator)
Ripple Rejection
(Main Regulator)
1133934
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1133935
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LP2956/LP2956A
Ripple Rejection
(Main Regulator)
Thermal Regulation
(Main Regulator)
1133937
1133936
Output Impedance
(Main Regulator)
Output Noise Voltage
(Main Regulator)
1133938
1133939
Feedback Bias Current
Divider Resistance
1133940
1133941
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LP2956/LP2956A
Dropout Characteristics
(Auxiliary Regulator)
Dropout vs Temperature
(Auxiliary Regulator)
1133942
1133943
Line Transient Response
(Auxiliary Regulator)
Current Limit vs Temperature
(Auxiliary Regulator)
1133944
1133945
Load Transient Response
(Auxiliary Regulator)
Load Transient Response
(Auxiliary Regulator)
1133946
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1133947
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LP2956/LP2956A
Ripple Rejection
(Auxiliary Regulator)
Output Impedance
(Auxiliary Regulator)
1133948
1133949
Output Noise Voltage
(Auxiliary Regulator)
Auxiliary Comparator
Sink Current
1133951
1133950
Error Output Voltage
Dropout Detection Comparator
Threshold Voltages
1133952
1133953
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LP2956/LP2956A
Application Hints
HEATSINK REQUIREMENTS
A heatsink may be required with the LP2956 depending on
the maximum power dissipation and maximum ambient temperature of the application. Under all expected 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 1 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 1 (the currents and power due to external resistive dividers are not included, and are typically
negligible).
1133910
*For best results, use L = 2H
FIGURE 2. Copper Heatsink Patterns
Table 2 shows some typical values of junction-to-ambient
thermal resistance (θ J-A) for values of L and W (1 oz. copper).
1133909
FIGURE 1. Current/Voltage Diagram
TABLE 2.
L (In.)
H (In.)
θJ-A (°C/W)
16-Pin
Plastic
1
0.5
70
DIP
2
1
60
3
1.5
58
4
0.19
66
6
0.19
66
16-Pin
1
0.5
83
Surface
2
1
70
Mount
3
1.5
67
6
0.19
69
4
0.19
71
2
0.19
73
Package
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) − T A(max)
where: TJ(max) is the maximum allowable junction temperature
TA(max) is the maximum ambient temperature
Using the calculated values for TR(max) and P(max), the required value for junction-to-ambient thermal resistance, θ (JA), can now be found:
θ(J-A) = TR(max)/P(max)
The heatsink for the LP2956 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 shown
in Table 1.
EXTERNAL CAPACITORS
A 2.2 μF (or greater) capacitor is required between the main
output pin and ground to assure stability. The auxiliary output
requires 10 μF to ground. Without these capacitors, 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 characteristic of the capacitors
is an ESR of 5Ω (or less) on the main regulator output and an
ESR of 1Ω (or less) on the auxiliary regulator output (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 these capacitors
may be increased without limit.
TABLE 1.
Part
Package
Pins
16-Pin Plastic DIP
4, 5, 12, 13
LP2956AIN
16-Pin Plastic DIP
4, 5, 12, 13
LP2956IM
16-Pin Surface Mt.
1, 8, 9, 16
LP2956AIM
16-Pin Surface Mt.
1, 8, 9, 16
LP2956IN
Figure 2 shows copper patterns which may be used to dissipate heat from the LP2956:
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LP2956/LP2956A
The main output requires less capacitance at lighter load currents. This capacitor can be reduced to 0.68 μF for currents
below 10 mA or 0.22 μF for currents below 1 mA.
Programming the main output for voltages below 5V requires
more output capacitance for stability. 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 ON MAIN OUTPUT
When setting the main output voltage using an external resistive divider, a minimum current of 10 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 the
specified value must be used to obtain test limit correlation.
1133911
*See Application Hints
**Drive with high to shut down
FIGURE 3. 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.
PROGRAMMING THE MAIN OUTPUT VOLTAGE
The main output 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 29V maximum rating using an
external pair of resistors (see Figure 3 ). The complete equation for the output voltage is:
DROPOUT DETECTION COMPARATOR
This comparator produces a logic “LOW” whenever the main
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-of-regulation condition can
result from low input voltage, current limiting, or thermal limiting.
Figure 4 gives a timing diagram showing the relationship between the main output voltage, the ERROR output, and input
voltage as the input voltage is ramped up and down to a regulator whose main output is programmed for 5V. The ERROR signal becomes low at about 1.3V input. It goes high at
about 5V input, where the main output equals 4.75V. Since
the dropout voltage is load dependent, the input voltage trip
points will vary with load current. The main 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 main output or some other supply voltage.
Using the main 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. The
resistor is not required if the output is unused.
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).
If IFB is ignored in the calculation of the output voltage, it will
produce a small error in VMAIN OUT. Choosing R2 = 100 kΩ will
reduce this error to 0.16% (typical) while increasing the resistor program current to 12 μA. Since the typical quiescent
current is 130 μA, this added current is negligible.
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LP2956/LP2956A
no longer proportional to the output voltage, so improvements
are more pronounced at higher output voltages.
1133912
*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)
1133913
FIGURE 4. ERROR Output Timing
If a single pull-up resistor is used to the regulator output, the
error flag may briefly rise up to about 1.3V as the input voltage
ramps up or down through the 0V to 1.3V region.
In some cases, this 1.3V signal may be mis-interpreted as a
false high by a μP which is still “alive” with 1.3V applied to it.
To prevent this, the user may elect to use two resistors which
are equal in value on the error output (one connected to
ground and the other connected to the regulator output).
If this two-resistor divider is used, the error output will only be
pulled up to about 0.6V (not 1.3V) during power-up or powerdown, so it can not be interpreted as a high signal. When the
regulator output is at 5V, the error output will be 2.5V, which
is still clearly a high signal.
where: VREF = 1.23V and IFB = −10 nA (typical)
FIGURE 5. Auxiliary Adjustable Regulator
AUXILIARY LDO OUTPUT
The LP2956 has an auxiliary LDO regulator output (which can
source up to 75 mA) that is adjustable for voltages from 1.23V
to 29V.
The output voltage is set by an external resistive divider, as
shown in Figure 5. The maximum output current is 75 mA,
and the output requires 10 μF from the output to ground for
stability, regardless of load current.
OUTPUT ISOLATION
The regulator outputs 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.
SHUTDOWN INPUT
The shutdown input equivalent circuit is shown in Figure 6.
The main regulator output is shut down when the NPN transitor is turned ON.
REDUCING MAIN OUTPUT NOISE
In reference applications it may be advantageous to reduce
the AC noise present on the main 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 3 ). The formula for selecting
the capacitor to be used is:
1133914
FIGURE 6. Shutdown Circuitry
The current into the input should be at least 0.5 μA to assure
the output shutdown function. A resistor may be placed in series with the input to minimize current draw in shutdown mode,
provided this minimum input current requirement is met.
IMPORTANT:
The shutdown input must not be left floating: a pull-down resistor (10 kΩ to 50 kΩ recommended) must be connected
between the shutdown input and ground in cases where the
input is not actively pulled low.
This gives a value of about 0.1μF. 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 noise 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
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LP2956/LP2956A
Schematic Diagram
LP2956/LP2956A
Typical Applications
1133916
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11339 Version 8 Revision 4
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LP2956/LP2956A
Physical Dimensions inches (millimeters) unless otherwise noted
16-Pin Surface Mount
Order Number LP2956IM or LP2956AIM
NS Package Number M16A
16-Pin Plastic Dual-In-Line Package
Order Number LP2956IN or LP2956AIN
NS Package Number N16A
17
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LP2956/LP2956A
16-Pin Ceramic Dual-In-Line Package
Order Number LP2956AMJ-QML or 5962-9554701QEA
NS Package Number J16A
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LP2956/LP2956A
19
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LP2956/LP2956A Dual Micropower Low-Dropout Voltage Regulators
Notes
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