1.5A Very L.D.O Voltage Regulator
FEATURES● High Current Capability 1.5A● Low Dropout Voltage 350mV● Low Ground Current● Accurate 1% Cuaranteed Tolerance● Extremely Fast Transient Response● Reverse-Battery and \"Load Dump\" Rotection● Zero-Current Shutdown Mode(5-Pin Version)● Error Flag Signals Output out-of-RegulationLM29150/1/2/3
TO-220 3/5L (5-Pin Versions)● Also Characterized For Smaller Loads With Industry -Leading Performance specifications● Fixed Voltage and Adjustable Versions TO-252 3/5LAPPLICATIONS● Battery Powered Equipment● High-Efficiency \" Green\" Computer System● Automotive Electronics● High-Efficiency Linear Power Supplies● High-Efficiency Post-Regulator For Switching Supply TO-263 3/5LORDERING INFORMATIONDeviceMarkingPinoutPackageLM29150: Three Therminal DevicesLM29150 - X.XPin 1= Input, 2= Ground, 3= OutputTO-220 3LLM29150RS - X.XLM29150 - X.XTO-252 3LLM29151: Five Therminal Fixed Voltage DevicesLM29150R - X.XPin 1= Enable, 2= Input, 3=Ground, 4=Output, 5= FlagTO-263 3LLM29151 - X.XTO-220 5LLM29152: Adjustable with ON/OFF controlPin 1= Enable, 2= Input, 3=Ground, 4=Output, 5= AdjustLM29151RS - X.XLM29151 - X.XTO-252 5LLM29151R - X.XLM29153: Adjustable with FlagTO-263 5LPin 1= Flag, 2= Input, 3=Ground, 4=Output, 5= AdjustLM29152/3TO-220 5LLM29152RS/3RS - X.XLM29152/3TO-252 5LLM29152R/3RTO-263 5L* LM29150 - X.X (X.X = Output Voltage = 2.5, 3.3, 5.0, 12V)* LM29151 - X.X (X.X = Output Voltage = 1.5V, 2.5V, 3.0V, 3.3V, 5.0V, 12V`
DESCRIPTION
The LM29150 are high current, high accuracy, low-dropout voltage regulators. Using process with a PNP passelement, these regulators feature 350mV (full load) dropout voltages and very low ground current.
These devices also find applications in lower current, low dropout-critical systems, where their tiny dropout voltage and graound current values are important attributes.
The LM29150 are fully protected against over current faults, reversed input polarity, reversed lead insertion, over temperature operation, and positive and negative transient voltage spikes. Five pin fixed voltage versionsfeature logic level ON/OFF control and an error flag which signals whenever the output falls out of regulation.On the LM29150 and LM29152, the ENABLE pin may be tied to Vin if it is not required for ON/OFF control.The LM29150 are available in 3- and 5- pinTO-220 and surface mount TO-263 packages.
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1.5A Very L.D.O Voltage Regulator
Block Diagram and typical Application Circuit
LM29150/1/2/3
94
* Feed Back network in fixed versions only**Adjustable version only
[ Block Diagram ]
LM
Vout=1.240V x [1+(R1/R2)]Figure2. Adjstable output voltage
configuration. For best results, the total
series resistance should be small enough topass the minimum regulator load current
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1.5A Very L.D.O Voltage Regulator
ABSOULTE MAXIMUM RATINGS
CHARACTERISTIC
Lead Temperature(Soldering, 5 Seconds)Storage Temperature RangeInput Supply Voltage(Note 1)
LM29150/1/2/3
Internally Limit
260℃-65℃ to + 150℃-20℃ to + 60℃'
OPERATING RATINGS
CHARACTERISTIC
Operating Junction TemperatureMaximum Operating Input Voltage
Internally Limit-40℃ to + 125℃'
26V
ELECTRICAL CHARACTERISTICS IOUT=100㎃, TA=25℃, unless otherwise specified
All measurements at Tj=25℃ unless otherwise noted. Bold Values are guaranteed across theoperating temperature range.
Adjustable versions are programmed to 5.0V
LM29150
LM29152
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1.5A Very L.D.O Voltage Regulator
LM29151 / LM29153LM29150/1/2/3
LM29151 / LM29152[ Note. ]
1. Maximum positive supply voltage of 60V must be of limited duration (<100msec) and duty cycle(≤1%). The maximum continuous supply voltage is 26V2. Full load current(IFL ) is defined as 1.5A
3. Dropout voltage is defined as the input-to-output differential when the output voltage drops to 99% of its nominal value with Vout to Vin
4. Vin = Vout(nominal) +1V. For example, use Vin =4.3V for a 3.3V regulator or use 6V for a 5V regulator. Employ pulse-testing procedures to minimize temperature rise.
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. Output voltage temperature coefficient is defined as the worst case voltage change divided by the total temperature range.
7. 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 a 200mA load pulse at Vin= 20V (a 4W pulse) for T= 10ms
8. Vref ≤ Vout ≤ (Vin -1V), 2.3V ≤ Vin ≤ 26V, 10mA<IL IFL, TJ< TJ Max
9. Comparator thresholds are expressed in terms of a voltage differential at the Adjust terminal below the nominal reference voltage measured at. 6V input. To express these thresholds in terms of output voltage change,
multiply by the error amplifier gain = Vout/Vref = (R1 +R2)/R2. For example, at a programmed output voltage of 5V, the Error output is guaranteed to go low when the output drops by 95mV x 5V/ 1.240V - 384mV.
Thresholds remain constant as a percent of Vout as Vout is varied, with the dropout warining occurring at typically 5% below nominal, 7.7% guaranteed.10. Ven ≤ 0.8V and Vin≤26V, Vout=0
11. When used in dual supply system where the regulator load is returned to a negative supply, the output Voltage must be diode clamped to ground.
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1.5A Very L.D.O Voltage Regulator
TYPICAL PERFORMANCE CHARACTERISTICS
LM29150/1/2/3
Figure 1. LM29150 Dropout Voltage vs,
Output CurrentFigure 2. LM29150 Dropout Voltage vs,
TemperatureFigure 3. LM29150- 5.0 Dropout
Characteristics
Figure 4. LM29150 Ground Current vs,
Supply VoltageFigure 5. LM29150 Ground Current vs,
TemperatureFigure 6. LM29150 Ground Current vs,
Temperature
Figure 7. LM29150-3.3 Output Voltage vs.
TemperatureFigure 8. LM29150-3.3 Short Circuit
Current vs. TemperatureFigure 9. LM29150 Ground Current vs.
Input Voltage
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1.5A Very L.D.O Voltage Regulator
LM29150/1/2/3
Applications Information
The LM29150 are high performance low-dropout voltage regulators suitable for all moderate to high-current voltage regulator applications. Their 350mV dropout voltage at full load make them especially valuable in battery powered systems and as high efficiency noise filters in
\"post-regulator\" applications. Unlike older NPN-pass transistor designs, dropout performance ofthe PNP output of these devices is limited merely by the low Vce saturation voltage.
The LM29150 family of regulators is fully protected from damage due to fault conditions. Current Limiting is provided. This limiting is linear; output current under overload conditions is constant. Thermal shutdown disables the device when the die temperature exceeds the 125℃ maximum safe operating temperature. Transient protection allows device survival even when the input voltage spikes between -20V and +60V. When the input voltage exceeds about 35V to 40V. The over voltage sensor temporarily disables the regulator.
Figure 3. Linear regulators require only two capacitorsfor operation.
Thermal Design
Linear regulators are simple to use. The most complicated design parameters to consider are thermal characteristics. Thermal design requires the following application-specific parameters:
*Maximum ambient temperature, TA*Output Current, IOUT*Output Voltage, VOUT*Input Voltage, VIN
First, we calculate the power dissipation of the regulator from these numbers and the device parameters from this datasheet.
PD=IOUT(1.01VIN-VOUT)
Where the ground current is approximated by 1% of IOUT. Then the heat sink thermalresistance is determined with this formula:
Where TJ MAX≤ 125℃ and ΘCS is between 0 and 2℃/W.
Capaitor Requirements
For stability and minimum output noise,a capacitor on the regulator output is necessary. Thevalue of this capacitor is dependent upon the output current; lower currents allow smaller
capcitors. LM29150 regulators are stable with the 10uF minimum capacitor values at full load.Where the regulator is powered from a source with a high AC impedance, a 0.1uF capacitorconnected between input and GND is recommended. This capacitor should have good characteristics to above 250kHz.
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1.5A Very L.D.O Voltage Regulator
LM29150/1/2/3
Minimum Load Current
The LM29150 regulators are specified between finite loads. If the output is too small, leakage currents is too small, leakage currents dominate and the output voltage rises. The 5mA minimum load current swamps any expected leakage current across the operating temperature range.Adjustable Regulator Design
Figure 4.
Adjustable Regulator with Resistors
VOUT=1.240V x [ 1+(R1/R2)]
The adjustable regulator versions, LM29152 and LM29153, allow programming the output voltage anywhere between 1.25V and the 26V maximum operating rating of the family.
Two resistors are used. Resistors can be quite large, up to 1MΩ, because of the very high input impedance and low bias current of the sense comparator: The resistor values are calculated by:
Where is VO the desired output voltage. Figure 4 shows component definition. Applications with widely varying load currents may scale the resistors to draw the minimum load current required for proper operation.
Error Flag
LM29151 and LM29153 versions feature and Error Flag, which looks at the output voltage and signals and error condition when this voltage and signals an error condition when this voltage drops 5% below its expected value. The error flag is an open-collector output that pulls low under fault conditions. It may sink 10mA. Low output voltage signifies a number of possible problems, including an over-current fault (the device is in current limit) and low input voltage.The flag output is inoperative during over temperature shutdwon conditions.
Enable input
LM29151 and LM29152 versions feature and enable (EN) input that allows ON/OFF control of the device. Special design allows \"zero\" current drain when the device is disabled-only microamperesof leakage current flows. The EN input has TTL/CMOS compatible thresholds for simple interfacingwith logic, or may be directly tied to ≤ 30V. Enabling the regulator requires approximately 20uA ofcurrent.
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