SS
IN
BIAS
GND
OUT VOUT
VIN
VBIAS
CIN
10 PF Ceramic
COUT
10 PF
Ceramic
CBIAS
1 PF
GND GND
LP38858-x.x
CSS
LP38858
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1.5A Fast-Response High-Accuracy LDO Linear Regulator with Soft-Start
Check for Samples: LP38858
1FEATURES DESCRIPTION
The LP38858 is a high current, fast response
2 Standard VOUT Values of 0.8V and 1.2V regulator which can maintain output voltage
Wide VBIAS Supply Operating Range of 3.0V to regulation with extremely low input to output voltage
5.5V drop. Fabricated on a CMOS process, the device
Stable with 10µF Ceramic Capacitors operates from two input voltages: VBIAS provides
voltage to drive the gate of the N-MOS power
Dropout Voltage of 130 mV (Typical) at 1.5A transistor, while VIN is the input voltage which
Load Current supplies power to the load. The use of an external
Precision Output Voltage across All Line and bias rail allows the part to operate from ultra low VIN
Load Conditions: voltages. Unlike bipolar regulators, the CMOS
architecture consumes extremely low quiescent
±1.0% VOUT for TJ= 25°C current at any output load current. The use of an N-
±2.0% VOUT for 0°C TJ+125°C MOS power transistor results in wide bandwidth, yet
±3.0% VOUT for -40°C TJ+125°C minimum external capacitance is required to maintain
Over-Temperature and Over-Current loop stability.
Protection The fast transient response of this device makes it
Available in 5 Lead TO-220 and DDPAK/TO-263 suitable for use in powering DSP, Microcontroller
Packages Core voltages and Switch Mode Power Supply post
regulators. The LP38858 is available in TO-220 and
Custom VOUT Values between 0.8V and 1.2V DDPAK/TO-263 5-Lead packages.
are Available Dropout Voltage: 130mV (typical) at 1.5A load
40°C to +125°C Operating Temperature Range current.
APPLICATIONS Low Ground Pin Current: 10 mA (typical) at 1.5A
load current.
ASIC Power Supplies In:
Desktops, Notebooks, and Graphics Cards, Soft-Start: Programmable Soft-Start time.
Servers Precision Output Voltage: ±1.0% for TJ= 25°C and
Gaming Set Top Boxes, Printers and ±2.0% for 0°C TJ+125°C, across all line and load
Copiers conditions
Server Core and I/O Supplies
DSP and FPGA Power Supplies
SMPS Post-Regulator
Typical Application Circuit
1Please 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.
2All trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date. Copyright © 2006–2013, Texas Instruments Incorporated
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
TAB
IS
GND
BIAS
OUT
GND
SS 1
2
3
4
5
IN
LP38858S-x.x
TAB
IS
GND
BIAS
OUT
GND
SS 1
2
3
4
5
IN
LP38858T-x.x
LP38858
SNVS462D OCTOBER 2006REVISED APRIL 2013
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Connection Diagram
Figure 1. DDPAK/TO-263–5 Package (Top View) Figure 2. TO220–5 Package (Top View)
See Package Number KTT0005B See Package Number NDH0005D
Pin Descriptions
TO-220–5 and DDPAK/TO-263–5 Packages
Pin # Pin Symbol Pin Description
1 SS Soft-Start capacitor connection. Used to slow the rise time of VOUT at turn-on.
2 IN The unregulated voltage input pin.
3 GND Ground
4 OUT The regulated output voltage pin.
5 BIAS The supply for the internal control and reference circuitry.
The TAB is a thermal connection that is physically attached to the backside of the
TAB TAB die, and used as a thermal heat-sink connection. See the Application Information
section for details.
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.
Absolute Maximum Ratings(1)(2)
Storage Temperature Range 65°C to +150°C
Lead Temperature Soldering, 5 seconds 260°C
ESD Rating Human Body Model(3) ±2 kV
Power Dissipation(4) Internally Limited
VIN Supply Voltage (Survival) 0.3V to +6.0V
VBIAS Supply Voltage (Survival) 0.3V to +6.0V
VSS Soft-Start Voltage (Survival) 0.3V to +6.0V
VOUT Voltage (Survival) 0.3V to +6.0V
IOUT Current (Survival) Internally Limited
Junction Temperature 40°C to +150°C
(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is intended to be functional, but does not ensure specific performance limits. For ensured specifications and conditions,
see the Electrical Characteristics.
(2) If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/Distributors for availability and
specifications.
(3) The human body model is a 100 pF capacitor discharged through a 1.5k resistor into each pin. Test method is per JESD22-A114. The
HBM rating for device pin 1 (SS) is ±1.5 kV.
(4) Device power dissipation must be de-rated based on device power dissipation (PD), ambient temperature (TA), and package junction to
ambient thermal resistance (θJA). Additional heat-sinking may be required to ensure that the device junction temperature (TJ) does not
exceed the maximum operating rating. See the Application Information section for details.
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Operating Ratings(1)
VIN Supply Voltage (VOUT + VDO) to VBIAS
VBIAS Supply Voltage 3.0V to 5.5V
IOUT 0 mA to 1.5A
Junction Temperature Range(2) 40°C to +125°C
(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is intended to be functional, but does not ensure specific performance limits. For ensured specifications and conditions,
see the Electrical Characteristics.
(2) Device power dissipation must be de-rated based on device power dissipation (PD), ambient temperature (TA), and package junction to
ambient thermal resistance (θJA). Additional heat-sinking may be required to ensure that the device junction temperature (TJ) does not
exceed the maximum operating rating. See the Application Information section for details.
Electrical Characteristics
Unless otherwise specified: VIN = VOUT(NOM) + 1V, VBIAS = 3.0V, IOUT = 10 mA, CIN = COUT = 10 µF, CBIAS = 1 µF, CSS = open.
Limits in standard type are for TJ= 25°C only; limits in boldface type apply over the junction temperature (TJ) range of -40°C
to +125°C. Minimum and Maximum limits are ensured through test, design, or statistical correlation. Typical values represent
the most likely parametric norm at TJ= 25°C, and are provided for reference purposes only.
Symbol Parameter Conditions MIN TYP MAX Units
VOUT(NOM) + 1V VIN VBIAS,-1.0 1.0
3.0V VBIAS 5.5V, 0
-3.0 3.0
10 mA IOUT 1.5A
VOUT VOUT Accuracy %
VOUT(NOM) + 1V VIN VBIAS,
3.0V VBIAS 5.5V, -2.0 0 2.0
10 mA IOUT 1.5A,
0°C TJ+125°C
ΔVOUT/ΔVIN Line Regulation, VIN(1) VOUT(NOM) + 1V VIN VBIAS - 0.04 - %/V
ΔVOUT/ΔVBIAS Line Regulation, VBIAS(1) 3.0V VBIAS 5.5V - 0.10 - %/V
ΔVOUT/ΔIOUT Output Voltage Load Regulation(2) 10 mA IOUT 1.5A - 0.2 - %/A
165
VDO Dropout Voltage(3) IOUT = 1.5A - 130 mV
180
LP38858-0.8 8.5
- 7.0
10 mA IOUT 1.5A 9.0
Quiescent Current Drawn from VIN
IGND(IN) mA
Supply LP38858-1.2 12
11
10 mA IOUT 1.5A 15
Quiescent Current Drawn from 3.8
IGND(BIAS) 10 mA IOUT 1.5A - 3.0 mA
VBIAS Supply 4.5
VBIAS rising until device is 2.20 2.70
UVLO Under-Voltage Lock-Out Threshold 2.45 V
functional 2.00 2.90
VBIAS falling from UVLO threshold 60 300
UVLO(HYS) Under-Voltage Lock-Out Hysteresis 150 mV
until device is non-functional 50 350
VIN = VOUT(NOM) + 1V,
ISC Output Short-Circuit Current - 4.5 - A
VBIAS = 3.0V, VOUT = 0.0V
Soft-Start
LP38858-0.8 11.0 13.5 16.0
rSS Soft-Start internal resistance k
LP38858-1.2 13.5 16.0 18.5
LP38858-0.8, CSS = 10 nF - 675 -
Soft-Start time
tSS μs
tSS = CSS × rSS × 5 LP38858-1.2, CSS = 10 nF - 800 -
(1) Output voltage line regulation is defined as the change in output voltage from nominal value resulting from a change in input voltage.
(2) Output voltage load regulation is defined as the change in output voltage from nominal value as the load current increases from no load
to full load.
(3) Dropout voltage is defined the as input to output voltage differential (VIN - VOUT) where the input voltage is low enough to cause the
output voltage to drop 2% from the nominal value.
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Electrical Characteristics (continued)
Unless otherwise specified: VIN = VOUT(NOM) + 1V, VBIAS = 3.0V, IOUT = 10 mA, CIN = COUT = 10 µF, CBIAS = 1 µF, CSS = open.
Limits in standard type are for TJ= 25°C only; limits in boldface type apply over the junction temperature (TJ) range of -40°C
to +125°C. Minimum and Maximum limits are ensured through test, design, or statistical correlation. Typical values represent
the most likely parametric norm at TJ= 25°C, and are provided for reference purposes only.
Symbol Parameter Conditions MIN TYP MAX Units
AC Parameters
VIN = VOUT(NOM) + 1V, - 80 -
f = 120 Hz
PSRR Ripple Rejection for VIN Input
(VIN) Voltage VIN = VOUT(NOM) + 1V, - 65 -
f = 1 kHz dB
VBIAS = VOUT(NOM) + 3V, - 58 -
f = 120 Hz
PSRR Ripple Rejection for VBIAS Voltage
(VBIAS)VBIAS = VOUT(NOM) + 3V, - 58 -
f = 1 kHz
Output Noise Density f = 120 Hz - 1 - µV/Hz
enBW = 10 Hz 100 kHz - 150 -
Output Noise Voltage µVRMS
VOUT = 1.8V BW = 300 Hz 300 kHz - 90 -
Thermal Parameters
Thermal Shutdown Junction
TSD - 160 -
Temperature °C
TSD(HYS) Thermal Shutdown Hysteresis - 10 -
TO-220-5 - 60 -
Thermal Resistance, Junction to
θJ-A Ambient(4) DDPAK/TO-263-5 - 60 - °C/W
TO-220-5 - 3 -
Thermal Resistance, Junction to
θJ-C Case(4) DDPAK/TO-263-5 - 3 -
(4) Device power dissipation must be de-rated based on device power dissipation (PD), ambient temperature (TA), and package junction to
ambient thermal resistance (θJA). Additional heat-sinking may be required to ensure that the device junction temperature (TJ) does not
exceed the maximum operating rating. See the Application Information section for details.
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Typical Performance Characteristics
Unless otherwise specified: TJ= 25°C, VIN = VOUT(NOM) + 1V, VBIAS = 3.0V, IOUT = 10 mA, CIN = COUT = 10 µF Ceramic, CBIAS =
1 µF Ceramic, CSS = open.
VBIAS Ground Pin Current (IGND(BIAS)) VBIAS Ground Pin Current (IGND(BIAS))
vs VBIAS vs Temperature
Figure 3. Figure 4.
VIN Ground Pin Current
vs Temperature Load Regulation vs Temperature
Figure 5. Figure 6.
Dropout Voltage (VDO) Output Current Limit (ISC)
vs Temperature vs Temperature
Figure 7. Figure 8.
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Typical Performance Characteristics (continued)
Unless otherwise specified: TJ= 25°C, VIN = VOUT(NOM) + 1V, VBIAS = 3.0V, IOUT = 10 mA, CIN = COUT = 10 µF Ceramic, CBIAS =
1 µF Ceramic, CSS = open.
UVLO Thresholds
VOUT vs Temperature vs Temperature
Figure 9. Figure 10.
Soft-Start Resistor (rSS) Soft-Start rSS Variation
vs Temperature vs Temperature
Figure 11. Figure 12.
VOUT
vs CSS, 10 nF to 47 nF VIN Line Transient Response
Figure 13. Figure 14.
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Typical Performance Characteristics (continued)
Unless otherwise specified: TJ= 25°C, VIN = VOUT(NOM) + 1V, VBIAS = 3.0V, IOUT = 10 mA, CIN = COUT = 10 µF Ceramic, CBIAS =
1 µF Ceramic, CSS = open.
VIN Line Transient Response VBIAS Line Transient Response
Figure 15. Figure 16.
VBIAS Line Transient Response Load Transient Response, COUT = 10 µF Ceramic
Figure 17. Figure 18.
Load Transient Response, COUT = 10 µF Ceramic Load Transient Response, COUT = 100 µF Ceramic
Figure 19. Figure 20.
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Typical Performance Characteristics (continued)
Unless otherwise specified: TJ= 25°C, VIN = VOUT(NOM) + 1V, VBIAS = 3.0V, IOUT = 10 mA, CIN = COUT = 10 µF Ceramic, CBIAS =
1 µF Ceramic, CSS = open.
Load Transient Response, COUT = 100 µF Ceramic Load Transient Response, COUT = 100 µF Tantalum
Figure 21. Figure 22.
Load Transient Response, COUT = 100 µF Tantalum VBIAS PSRR
Figure 23. Figure 24.
VIN PSRR Output Noise
Figure 25. Figure 26.
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GND
OUT
IN
BIAS
SS
Under-Voltage
Lock-Out
Thermal
Shut Down
VREF
0.6V
ILIMIT
LP38858-x.x
rSS
LP38858
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SNVS462D OCTOBER 2006REVISED APRIL 2013
Block Diagram
APPLICATION INFORMATION
EXTERNAL CAPACITORS
To assure regulator stability, input and output capacitors are required as shown in the Typical Application Circuit.
Output Capacitor
A minimum output capacitance of 10 µF, ceramic, is required for stability. The amount of output capacitance can
be increased without limit. The output capacitor must be located less than 1 cm from the output pin of the IC and
returned to the device ground pin with a clean analog ground.
Only high quality ceramic types such as X5R or X7R should be used, as the Z5U and Y5F types do not provide
sufficient capacitance over temperature.
Tantalum capacitors will also provide stable operation across the entire operating temperature range. However,
the effects of ESR may provide variations in the output voltage during fast load transients. Using the minimum
recommended 10 µF ceramic capacitor at the output will allow unlimited capacitance, Tantalum and/or
Aluminum, to be added in parallel.
Input Capacitor
The input capacitor must be at least 10 µF, but can be increased without limit. It's purpose is to provide a low
source impedance for the regulator input. A ceramic capacitor, X5R or X7R, is recommended.
Tantalum capacitors may also be used at the input pin. There is no specific ESR limitation on the input capacitor
(the lower, the better).
Aluminum electrolytic capacitors can be used, but are not recommended as their ESR increases very quickly at
cold temperatures. They are not recommended for any application where the ambient temperature falls below
0°C.
Bias Capacitor
The capacitor on the bias pin must be at least 1 µF, and can be any good quality capacitor (ceramic is
recommended).
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INPUT VOLTAGE
The input voltage (VIN) is the high current external voltage rail that will be regulated down to a lower voltage,
which is applied to the load. The input voltage must be at least VOUT + VDO, and no higher than whatever values
is used for VBIAS.
BIAS VOLTAGE
The bias voltage (VBIAS) is a low current external voltage rail required to bias the control circuitry and provide
gate drive for the N-FET pass transistor. The bias voltage must be in the range of 3.0V to 5.5V to ensure proper
operation of the device.
UNDER VOLTAGE LOCKOUT
The bias voltage is monitored by a circuit which prevents the device from functioning when the bias voltage is
below the Under-Voltage Lock-Out (UVLO) threshold of approximately 2.45V.
As the bias voltage rises above the UVLO threshold the device control circuitry becomes active. There is
approximately 150 mV of hysteresis built into the UVLO threshold to provide noise immunity.
When the bias voltage is between the UVLO threshold and the Minimum Operating Rating value of 3.0V the
device will be functional, but the operating parameters will not be within the specified limits.
SUPPLY SEQUENCING
There is no requirement for the order that VIN or VBIAS are applied or removed.
One practical limitation is that the Soft-Start circuit starts charging CSS when VBIAS rises above the UVLO
threshold. If the application of VIN is delayed beyond this point the benefits of Soft-Start will be compromised.
In any case, the output voltage cannot be ensured until both VIN and VBIAS are within the range of specified
operating values.
If used in a dual-supply system where the regulator output load is returned to a negative supply, the output pin
must be diode clamped to ground. A Schottky diode is recommended for this diode clamp.
REVERSE VOLTAGE
A reverse voltage condition will exist when the voltage at the output pin is higher than the voltage at the input pin.
Typically this will happen when VIN is abruptly taken low and COUT continues to hold a sufficient charge such that
the input to output voltage becomes reversed.
The NMOS pass element, by design, contains no body diode. This means that, as long as the gate of the pass
element is not driven, there will not be any reverse current flow through the pass element during a reverse
voltage event. The gate of the pass element is not driven when VBIAS is below the UVLO threshold.
When VBIAS is above the UVLO threshold the control circuitry is active and will attempt to regulate the output
voltage. Since the input voltage is less than the output voltage the control circuit will drive the gate of the pass
element to the full VBIAS potential when the output voltage begins to fall. In this condition, reverse current will flow
from the output pin to the input pin , limited only by the RDS(ON) of the pass element and the output to input
voltage differential. Discharging an output capacitor up to 1000 μF in this manner will not damage the device as
the current will decay rapidly. However, continuous reverse current should be avoided.
SOFT-START
The LP38858 incorporates a Soft-Start function that reduces the start-up current surge into the output capacitor
(COUT) by allowing VOUT to rise slowly to the final value. This is accomplished by controlling VREF at the SS pin.
The soft-start timing capacitor (CSS) is internally held to ground until VBIAS rises above the Under-Voltage Lock-
Out threshold (ULVO).
VREF will rise at an RC rate defined by the internal resistance of the SS pin (rSS), and the external capacitor
connected to the SS pin. This allows the output voltage to rise in a controlled manner until steady-state
regulation is achieved. Typically, five time constants are recommended to assure that the output voltage is
sufficiently close to the final steady-state value. During the soft-start time the output current can rise to the built-in
current limit.
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Soft-Start Time = CSS × rSS × 5 (1)
Since the VOUT rise will be exponential, not linear, the in-rush current will peak during the first time constant (τ),
and VOUT will require four additional time constants (4τ) to reach the final value (5τ) .
After achieving normal operation, should VBIAS fall below the ULVO threshold the device output will be disabled
and the Soft-Start capacitor (CSS) discharge circuit will become active. The CSS discharge circuit will remain
active until VBIAS falls to 500 mV (typical). When VBIAS falls below 500 mV (typical), the CSS discharge circuit will
cease to function due to a lack of sufficient biasing to the control circuitry.
Since VREF appears on the SS pin, any leakage through CSS will cause VREF to fall, and thus affect VOUT. A
leakage of 50 nA (about 10 M) through CSS will cause VOUT to be approximately 0.1% lower than nominal, while
a leakage of 500 nA (about 1 M) will cause VOUT to be approximately 1% lower than nominal. Typical ceramic
capacitors will have a factor of 10X difference in leakage between 25°C and 85°C, so the maximum ambient
temperature must be included in the capacitor selection process.
Typical CSS values will be in the range of 1 nF to 100 nF, providing typical Soft-Start times in the range of 70 μs
to 7 ms (5τ). Values less than 1 nF can be used, but the Soft-Start effect will be minimal. Values larger than 100
nF will provide soft-start, but may not be fully discharged if VBIAS falls from the UVLO threshold to less than 500
mV in less than 100 µs.
Figure 27 shows the relationship between the COUT value and a typical CSS value.
Figure 27. Typical CSS vs COUT Values
The CSS capacitor must be connected to a clean ground path back to the device ground pin. No components,
other than CSS, should be connected to the SS pin, as there could be adverse effects to VOUT.
If the Soft-Start function is not needed the SS pin should be left open, although some minimal capacitance value
is always recommended.
POWER DISSIPATION AND HEAT-SINKING
Additional copper area for heat-sinking may be required depending on the maximum device dissipation (PD) and
the maximum anticipated ambient temperature (TA) for the device. Under all possible conditions, the junction
temperature must be within the range specified under operating conditions.
The total power dissipation of the device is the sum of three different points of dissipation in the device.
The first part is the power that is dissipated in the NMOS pass element, and can be determined with the
formula:
PD(PASS) = (VIN - VOUT) × IOUT (2)
The second part is the power that is dissipated in the bias and control circuitry, and can be determined with the
formula:
PD(BIAS) = VBIAS × IGND(BIAS)
where
IGND(BIAS) is the portion of the operating ground current of the device that is related to VBIAS (3)
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THA d TJA - (TCH + TJC)
d
'TJ
PD
TJA
'TJ = TJ(MAX) - TA(MAX)
LP38858
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The third part is the power that is dissipated in portions of the output stage circuitry, and can be determined with
the formula:
PD(IN) = VIN × IGND(IN)
where
IGND(IN) is the portion of the operating ground current of the device that is related to VIN (4)
The total power dissipation is then:
PD= PD(PASS) + PD(BIAS) + PD(IN) (5)
The maximum allowable junction temperature rise (ΔTJ) depends on the maximum anticipated ambient
temperature (TA) for the application, and the maximum allowable operating junction temperature (TJ(MAX)) .
(6)
The maximum allowable value for junction to ambient Thermal Resistance, θJA, can be calculated using the
formula:
(7)
Heat-Sinking the TO-220 Package
The TO-220-5 package has a θJA rating of 60°C/W and a θJC rating of 3°C/W. These ratings are for the package
only, no additional heat-sinking, and with no airflow. If the needed θJA, as calculated above, is greater than or
equal to 60°C/W then no additional heat-sinking is required since the package can safely dissipate the heat and
not exceed the operating TJ(MAX). If the needed θJA is less than 60°C/W then additional heat-sinking is needed.
The thermal resistance of a TO-220 package can be reduced by attaching it to a heat sink or a copper plane on
a PC board. If a copper plane is to be used, the values of θJA will be same as shown in next section for
DDPAK/TO-263 package.
The heat-sink to be used in the application should have a heat-sink to ambient thermal resistance, θHA:
where
θJA is the required total thermal resistance from the junction to the ambient air
θCH is the thermal resistance from the case to the surface of the heart-sink
θJC is the thermal resistance from the junction to the surface of the case (8)
For this equation, θJC is about 3°C/W for a TO-220 package. The value for θCH depends on method of
attachment, insulator, etc. θCH varies between 1.5°C/W to 2.5°C/W. Consult the heat-sink manufacturer
datasheet for details and recommendations.
Heat-Sinking the DDPAK/TO-263 Package
The DDPAK/TO-263 package has a θJA rating of 60°C/W, and a θJC rating of 3°C/W. These ratings are for the
package only, no additional heat-sinking, and with no airflow.
The DDPAK/TO-263 package uses the copper plane on the PCB as a heat-sink. The tab of this package is
soldered to the copper plane for heat sinking. shows a curve for the θJA of DDPAK/TO-263 package for different
copper area sizes, using a typical PCB with 1 ounce copper and no solder mask over the copper area for heat-
sinking.
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Figure 28. θJA vs Copper (1 Ounce) Area for the DDPAK/TO-263 package
Figure 28 shows that increasing the copper area beyond 1 square inch produces very little improvement. The
minimum value for θJA for the DDPAK/TO-263 package mounted to a PCB is 32°C/W.
Figure 29 shows the maximum allowable power dissipation for DDPAK/TO-263 packages for different ambient
temperatures, assuming θJA is 35°C/W and the maximum junction temperature is 125°C.
Figure 29. Maximum Power Dissipation vs Ambient Temperature for the DDPAK/TO-263 Package
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REVISION HISTORY
Changes from Revision C (April 2013) to Revision D Page
Changed layout of National Data Sheet to TI format .......................................................................................................... 13
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PACKAGE OPTION ADDENDUM
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Addendum-Page 1
PACKAGING INFORMATION
Orderable Device Status
(1)
Package Type Package
Drawing Pins Package
Qty Eco Plan
(2)
Lead/Ball Finish
(6)
MSL Peak Temp
(3)
Op Temp (°C) Device Marking
(4/5)
Samples
LP38858S-0.8/NOPB ACTIVE DDPAK/
TO-263 KTT 5 45 Pb-Free (RoHS
Exempt) CU SN Level-3-245C-168 HR -40 to 125 LP38858S
-0.8
LP38858S-1.2 NRND DDPAK/
TO-263 KTT 5 45 TBD Call TI Call TI -40 to 125 LP38858S
-1.2
LP38858S-1.2/NOPB ACTIVE DDPAK/
TO-263 KTT 5 45 Pb-Free (RoHS
Exempt) CU SN Level-3-245C-168 HR -40 to 125 LP38858S
-1.2
LP38858SX-0.8/NOPB ACTIVE DDPAK/
TO-263 KTT 5 500 Pb-Free (RoHS
Exempt) CU SN Level-3-245C-168 HR -40 to 125 LP38858S
-0.8
LP38858SX-1.2/NOPB ACTIVE DDPAK/
TO-263 KTT 5 500 Pb-Free (RoHS
Exempt) CU SN Level-3-245C-168 HR -40 to 125 LP38858S
-1.2
LP38858T-0.8/NOPB ACTIVE TO-220 NDH 5 45 Green (RoHS
& no Sb/Br) CU SN Level-1-NA-UNLIM -40 to 125 LP38858T
-0.8
LP38858T-1.2/NOPB ACTIVE TO-220 NDH 5 45 Green (RoHS
& no Sb/Br) CU SN Level-1-NA-UNLIM -40 to 125 LP38858T
-1.2
(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)
(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.
PACKAGE OPTION ADDENDUM
www.ti.com 1-Nov-2013
Addendum-Page 2
(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.
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device Package
Type Package
Drawing Pins SPQ Reel
Diameter
(mm)
Reel
Width
W1 (mm)
A0
(mm) B0
(mm) K0
(mm) P1
(mm) W
(mm) Pin1
Quadrant
LP38858SX-0.8/NOPB DDPAK/
TO-263 KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2
LP38858SX-1.2/NOPB DDPAK/
TO-263 KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2
PACKAGE MATERIALS INFORMATION
www.ti.com 23-Sep-2013
Pack Materials-Page 1
*All dimensions are nominal
Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm)
LP38858SX-0.8/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0
LP38858SX-1.2/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0
PACKAGE MATERIALS INFORMATION
www.ti.com 23-Sep-2013
Pack Materials-Page 2
MECHANICAL DATA
NDH0005D
www.ti.com
MECHANICAL DATA
KTT0005B
www.ti.com
BOTTOM SIDE OF PACKAGE
TS5B (Rev D)
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