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LX8587X-xx
TM (R)
3A Low Dropout Positive Regulators
PRODUCTION DATA SHEET
DESCRIPTION The LX8587/87A Series ICs are positive regulators designed to provide 3A output current. Pentium(R) Processor and Power PCTM applications requiring fast transient response are ideally suited for this product family. The LX8587A is guaranteed to have <1.2 dropout at 3A and the LX8587 < 1.3V at the same current, making them ideal to provide well-regulated outputs of 2.5V to 3.6V using a 5V input supply. Fixed versions are also available and specified in the Available Options table below. Current limit is trimmed about 3.1A to ensure adequate output current and controlled short-circuit current. On-chip thermal limiting provides protection against any combination of overload conditions that would create excessive junction temperatures. The LX8587/87A family of products are available in the TO-220 through hole, the TO-263 surface-mount, and the TO-252 surface-mount packages. For higher current applications see the LX8585 and the LX8584 data sheets.
KEY FEATURES
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Three-Terminal Adjustable Or Fixed Output Guaranteed < 1.2V Headroom At 3A (LX8587A) Guaranteed < 1.3V Headroom At 3A (LX8587) Output Current of 3A Fast Transient Response 1% Voltage Reference Initial Accuracy Output Short Circuit Protection Built-In Thermal Shutdown APPLICATIONS Pentium Processor Supplies Power PC Supplies Microprocessor Supplies Low Voltage Logic Supplies Post Regulator for Switching Supply ASIC & Low Voltage Chipset Supplies Graphics & Sound Cards Processor I/O Supply OUTPUT VOLTAGE
Adjustable 1.5V 3.3V
IMPORTANT: For the most current data, consult MICROSEMI's website: http://www.microsemi.com
PRODUCT HIGHLIGHT TYPICAL APPLICATION OF THE LX8587/87A IN A 5V TO 3.3V MOTHERBOARD
IN
VIN > 4.75V + *1500F 6MV1500GX Sanyo
LX8587A
ADJ
200 1%
OUT
121 1% +
3.3V at 3A
1500F 2x 6MV1500GX Sanyo
PART #
LX8587/87A-00
The output capacitors must be low ESR and low ESL type for good transient response.
LX8587/87A-15 LX8587/87A-33
Table 1 - Available Options
LX8587X LX8587X
TA (C) 0 to 125
Max Dropout Voltage 1.3V 1.2V
DT
PACKAGE ORDER INFO Plastic TO-220 Plastic TO-252 P 3-Pin (D-Pak) 3-Pin
RoHS Compliant Transition DC: 0543
DD
Plastic TO-263 3-Pin
RoHS Compliant Transition DC: 0532
RoHS Compliant Transition DC: 0535
LX8587-xxCDT LX8587A-xxCDT
LX8587-xxCP LX8587A-xxCP
LX8587-xxCDD LX8587A-xxCDD
Note: Available in Tape & Reel. Append the letters "TR" to the part number. (i.e. LX8587-00CP-TR)
Copyright (c) 2000 Rev. 2.0a, 2005-10-25
Microsemi
Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 1
LX8587X-xx
TM (R)
3A Low Dropout Positive Regulators
PRODUCTION DATA SHEET
ABSOLUTE MAXIMUM RATINGS Power Dissipation ................................................................................... Internally Limited Input Voltage ................................................................................................................ 10V Input to Output Voltage Differential............................................................................. 10V Maximum Output Current............................................................................................... 5A Maximum Operating Junction Temperature .............................................................. 150C Storage Temperature Range........................................................................ -65C to 150C Peak Package Solder Reflow Temp. (40 seconds max. exposure) .................260C (+0,-5)
Note: Exceeding these ratings could cause damage to the device. All voltages are with respect to Ground. Currents are positive into, negative out of specified terminal.
PACKAGE PIN OUT
TAB is VOUT
3
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VIN VOUT
ADJ / GND*
2 1
DD PACKAGE (3-PIN)
(Top View)
TAB is VOUT
3
VIN VOUT ADJ/ GND *
THERMAL DATA
2
DD
Plastic TO-263 3-Pin 60C/W 2.7C/W 60C/W 2.7C/W 60C/W 2.7C/W
1
THERMAL RESISTANCE-JUNCTION TO AMBIENT, JA THERMAL RESISTANCE-JUNCTION TO TAB, JT
DT PACKAGE (3-PIN)
(Top View)
P
Plastic TO-220 3-Pin
TAB is VOUT
3
THERMAL RESISTANCE-JUNCTION TO AMBIENT, JA THERMAL RESISTANCE-JUNCTION TO TAB, JT
VIN VOUT ADJ / GND*
2
1
DT
Plastic TO-252 3-Pin
THERMAL RESISTANCE-JUNCTION TO AMBIENT, JA THERMAL RESISTANCE-JUNCTION TO TAB, JT
P PACKAGE (3-PIN)
(Top View)
*Pin 1 is GND for fixed voltage versions RoHS 100% Matte Tin Lead Finish
Junction Temperature Calculation: TJ = TA + (PD x JT). The JA & JT numbers are guidelines for the thermal performance of the device/pc-board system. All of the above assume no ambient airflow.
PACKAGE DATA PACKAGE DATA
Copyright (c) 2000 Rev. 2.0a, 2005-10-25
Microsemi
Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
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LX8587X-xx
TM (R)
3A Low Dropout Positive Regulators
PRODUCTION DATA SHEET
ELECTRICAL CHARACTERISTICS
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Unless otherwise specified, the following specifications apply over the operating ambient temperature for the LX8587X-xx with 0C TA 125C. Test conditions: VIN -VOUT = 3V; IOUT = 3A. Low duty cycle pulse testing techniques are used which maintains junction and case temperatures equal to the ambient temperature. Parameter
LX8587-00/87A-00 (ADJUSTABLE) Reference Voltage Line Regulation (Note 2) Load Regulation (Note 2) Thermal Regulation Ripple Rejection (Note 3) Adjust Pin Current Adjust Pin Current Change Dropout Voltage LX8587-00 LX8587A-00 Minimum Load Current Maximum Output Current Temperature Stability Long Term Stability (Note 3) RMS Output Noise (% of VOUT) (Note 3) LX8587-15/87A-15 (1.5V FIXED) Output Voltage Line Regulation (note 2) Load Regulation (note 2) Thermal Regulation (note 3) Ripple Rejection (note 3) Quiescent Current Dropout Voltage LX8587-15 LX8587A-15 IQ V IADJ IADJ V IOUT(MIN) IOUT(MAX) VOUT(T) VOUT(t) TA = 125C, 1000 hours 0.003 10mA < IOUT < 3A, 1.5V < (VIN -VOUT), VIN < 7V VREF = 1%, IOUT = 3A VREF = 1%, IOUT = 3A VIN < 7V 1.4V < (VIN - VOUT), VIN < 7V 3 VREF VREF (VIN) VREF (IOUT) VOUT (Pwr) IOUT = 10mA, TA = 25C 10mA < IOUT < 3A, 1.5V < (VIN - VOUT), VIN <7V, P < PMAX IOUT = 10mA, 1.5V < (VIN - VOUT), VIN < 7V VIN - VOUT = 3V, 10mA < IOUT < 3A TA = 25C, 20ms pulse VOUT = 3.3V, f= 120Hz, COUT = 100F Tantalum, VIN = 5V, CADJ = 10F, IOUT = 3A 65 1.238 1.225 1.250 1.250 0.035 0.1 0.01 83 55 0.2 1.1 1 2 5 0.25 1 100 5 1.3 1.2 10 1.262 1.275 0.20 0.5 0.02 V V % % %/W dB A A V V mA A % % %
Symbol
Test Conditions
Min
LX8587X-xx Typ Max
Units
VOUT(RMS) TA = 25C, 10Hz < f < 10kHz
VOUT VOUT (VIN) VOUT (IOUT) VOUT (Pwr)
VIN = 5V, IOUT = 0mA, TA = 25C 3.0V < VIN < 7V, 0mA < IOUT < 3A, P < PMAX 4.75V < VIN < 7V 4.75V < VIN < 10V VIN = 5V, 0mA < IOUT < IOUT(MAX) TA = 25C, 20ms pulse COUT = 100F (Tantalum), IOUT = 3A 0mA < IOUT < IOUT(MAX), 4.75V < VIN < 10V VOUT = 1%, IOUT < IOUT(MAX) VOUT = 1%, IOUT < IOUT(MAX)
1.485 1.470
1.50 1.50 1 2 5 0.01
1.515 1.530 6 10 7.5 0.02
V V mV mV mV %/W dB
60
75 4 1.1 1 10 1.3 1.2
mA V V
ELECTRICALS ELECTRICALS
Copyright (c) 2000 Rev. 2.0a, 2005-10-25
Microsemi
Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
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LX8587X-xx
TM (R)
3A Low Dropout Positive Regulators
PRODUCTION DATA SHEET
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ELECTRICAL CHARACTERISTICS (CONTINUED) Unless otherwise specified, the following specifications apply over the operating ambient temperature for the LX8585x-xxC with 0C TA 125C and the LX8585-xxI with -25C TA 125C except where otherwise noted. Test conditions: VIN -VOUT = 3V; IOUT = 3A. Low duty cycle pulse testing techniques are used which maintains junction and case temperatures equal to the ambient temperature. Parameter Symbol Test Conditions LX8587X-xx Typ Max
5.0 0.25 TA=125C, 1000 hours TA=25C, 10Hz < f < 10kHz 0.3 0.003 1
Min
3.0
Units
LX8587-15 / 8587A-15 (1.5V FIXED)(CONTINUED) Maximum Output Current Temperature Stability (Note 3) Long Term Stability (Note 3) RMS Output Noise (% of VOUT) (Note 3) LX8587-33/87A-33 (3.3V FIXED) Output Voltage VOUT VIN=5V, IOUT=0mA, TA=25C 4.75V < VIN < 10V, 0mA < IOUT < 3A, P < PMAX 4.75V < VIN < 7V 4.75V < VIN < 10V VIN=5V, 0mA < IOUT < IOUT(MAX) TA=25C, 20ms pulse COUT=100F (Tantalum), IOUT=3A IQ LX8587-33 LX8587A-33 Maximum Output Current Temperature Stability (Note 3) Long Term Stability (Note 3) RMS Output Noise (% of VOUT) (Note 3) V IOUT(MAX) VOUT (T) VOUT (t) VOUT (RMS) TA=125C, 1000 hours TA=25C, 10Hz < f < 10kHz 0mA < IOUT < IOUT(MAX), 4.75V < VIN < 10V VOUT=1%, IOUT < IOUT(MAX) VOUT=1%, IOUT < IOUT(MAX) VIN < 7V 3 60 3.267 3.235 3.3 3.3 1 2 5 0.01 75 4 1.1 1 5.0 0.25 0.3 0.003 1 10 1.3 1.2 3.333 3.365 6 10 15 0.02 V V mV mV mV %/W dB mA V V A % % % IOUT(MAX) VOUT(T) VOUT (t) VOUT (RMS) VIN < 7V A % % %
Line Regulation (Note 2) Load Regulation (Note 2) Thermal Regulation Ripple Rejection (Note 3) Quiescent Current Dropout Voltage
VOUT(VIN) VOUT (IOUT) VOUT (Pwr)
Note 2 Note 3
Regulation is measured at constant junction temperature, using pulse testing with a low duty cycle. Changes in output voltage due to heating effects are covered under the specification for thermal regulation. These parameters, although guaranteed, are not tested in production.
ELECTRICALS ELECTRICALS
Copyright (c) 2000 Rev. 2.0a, 2005-10-25
Microsemi
Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
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LX8587X-xx
TM (R)
3A Low Dropout Positive Regulators
PRODUCTION DATA SHEET
APPLICATION NOTES
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The LX8587/87A Series ICs are easy to use Low-Dropout (LDO) voltage regulators. They have all of the standard selfprotection features expected of a voltage regulator: short circuit protection, safe operating area protection and automatic thermal shutdown if the device temperature rises above approximately 165C. Use of an output capacitor is REQUIRED with the LX8587/87A series. Please see the table below for recommended minimum capacitor values. These regulators offer a more tightly controlled reference voltage tolerance and superior reference stability when measured against the older pin-compatible regulator types that they replace. STABILITY The output capacitor is part of the regulator's frequency compensation system. Many types of capacitors are available, with different capacitance value tolerances, capacitance temperature coefficients, and equivalent series impedances. For all operating conditions, connection of a 220F aluminum electrolytic capacitor or a 47F (<400m ESR) solid tantalum capacitor between the output terminal and ground will guarantee stable operation. If a bypass capacitor is connected between the output voltage adjust (ADJ) pin and ground, ripple rejection will be improved (please see the section entitled "RIPPLE REJECTION"). When ADJ pin bypassing is used, the required output capacitor value increases. Output capacitor values of 220F (aluminum) or 47F (tantalum) provide for all cases of bypassing the ADJ pin. If an ADJ pin bypass capacitor is not used, smaller output capacitor values are adequate. The table below shows recommended minimum capacitance values for operation. Minimum Capacitor Values INPUT 10F 10F OUTPUT 15F Tantalum, 100F Aluminum 47F Tantalum, 220F Aluminum ADJ None 15F
Power Supply
IN
OUT
Minimum Load (Larger resistor) Full Load (Smaller resistor)
ADJ
RDSON << RL Star Ground
10ms
1 sec
FIGURE 1 - DYNAMIC INPUT AND OUTPUT TEST
To ensure good transient response from the power supply system under rapidly changing current load conditions, designers generally use several output capacitors connected in parallel. Such an arrangement serves to minimize the effects of the parasitic resistance (ESR) and inductance (ESL) that are present in all capacitors. Cost-effective solutions that sufficiently limit ESR and ESL effects generally result in total capacitance values in the range of hundreds to thousands of microfarads, which is more than adequate to meet regulator output capacitor specifications. Output capacitance values may be increased without limit. The circuit shown in Figure 1 can be used to observe the transient response characteristics of the regulator in a power system under changing loads. The effects of different capacitor types and values on transient response parameters, such as overshoot and under-shoot, can be compared quickly in order to develop an optimum solution.
OVERLOAD RECOVERY Like almost all IC power regulators, the LX8587/87A regulators are equipped with Safe Operating Area (SOA) protection. The SOA circuit limits the regulator's maximum output current to progressively lower values as the input-to-output voltage difference increases. By limiting the maximum output current, the SOA circuit keeps the amount of power that is dissipated in the regulator itself within safe limits for all values of input-to-output voltage within the operating range of the regulator. The LX8587/87A SOA protection system is designed to be able to supply some output current for all values of input-tooutput voltage, up to the device breakdown voltage. Under some conditions, a correctly operating SOA circuit may prevent a power supply system from returning to regulated operation after removal of an intermittent short circuit at the output of the regulator. This is a normal mode of operation, which can be seen, in most similar products, including older devices such as 7800 series regulators. It is most likely to occur when the power system input voltage is relatively high and the load impedance is relatively low. When the power system is started "cold", both the input and output voltages are very close to zero. The output voltage closely follows the rising input voltage, and the input-to-output voltage difference is small. The SOA circuit therefore permits the regulator to supply large amounts of current as needed to develop the designed voltage level at the regulator output. Now consider the case where the regulator is supplying regulated voltage to a resistive load under steady state conditions. A moderate input-to-output voltage appears across the regulator but the voltage difference is small enough that the SOA circuitry allows sufficient current to flow through the regulator to develop the designed output voltage across the load resistance. If the output resistor is short-circuited to ground, the input-to-output voltage difference across the regulator suddenly becomes larger by the amount of voltage that had appeared across the load resistor. The SOA circuit reads the increased input-to-output voltage, and cuts back the amount of current that it will permit the regulator to supply to its output terminal. When the short circuit across the output resistor is removed, all the regulator output current will again flow through the output resistor. The maximum current that the regulator can supply to the resistor will be limited by the SOA circuit, based on the large input-to-output
Page 5
APPLICATIONS APPLICATIONS
Copyright (c) 2000 Rev. 2.0a, 2005-10-25
Microsemi
Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
LX8587X-xx
TM (R)
3A Low Dropout Positive Regulators
PRODUCTION DATA SHEET
APPLICATION NOTES (CONTINUED)
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OVERLOAD RECOVERY (continued) voltage across the regulator at the time the short circuit is removed from the output. If this limited current is not sufficient to develop the designed voltage across the output resistor, the voltage will stabilize at some lower value, and will never reach the designed value. Under these circumstances, it may be necessary to cycle the input voltage down to zero in order to make the regulator output voltage return to regulation. RIPPLE REJECTION Ripple rejection can be improved by connecting a capacitor between the ADJ pin and ground. The value of the capacitor should be chosen so that the impedance of the capacitor is equal in magnitude to the resistance of R1 at the ripple frequency. The capacitor value can be determined by using this equation:
VIN
IN
OUT
VREF
R1
VOUT
ADJ
IADJ 50A
R2
R2 VOUT = VREF 1 + + I ADJ R 2 R1
FIGURE 2 - BASIC ADJUSTABLE REGULATOR LOAD REGULATION Because the LX8587/87A regulators are three-terminal devices, it is not possible to provide true remote load sensing. Load regulation will be limited by the resistance of the wire connecting the regulator to the load. The data sheet specification for load regulation is measured at the bottom of the package. Negative side sensing is a true Kelvin connection, with the bottom of the output divider returned to the negative side of the load. Although it may not be immediately obvious, best load regulation is obtained when the top of the resistor divider, (R1), is connected directly to the case of the regulator, not to the load. This is illustrated in Figure 3. If R1 were connected to the load, the effective resistance between the regulator and the load would be:
C=
where: C
1 (6.28 x FR x R1)
the value of the capacitor in Farads; select an equal or larger standard value. FR the ripple frequency in Hz R1 the value of resistor R1 in ohms At a Ripple frequency of 120Hz, with R1= 100:
C=
1 = 13.3F (6.28 x 120Hz x100 )
The closest equal or larger standard value should be used, in this case, 15F. When an ADJ pin bypass capacitor is used, output ripple amplitude will be essentially independent of the output voltage. If an ADJ pin bypass capacitor is not used, output ripple will be proportional to the ratio of the output voltage to the reference voltage:
R 2 + R1 RPeff = RP x R1
where: RP Actual parasitic line resistance. When the circuit is connected as shown in Figure 3, the parasitic resistance appears as its actual value, rather than the higher RPeff.
M=
where: M
VOUT VREF
a multiplier for the ripple seen when the ADJ pin is optimally bypassed. VREF 1.25V For example, if VOUT = 2.5V the output ripple will be:
IN
VIN
OUT
RP Parasitic Line Resistance
M=
2 .5 V =2 1.25V
Output ripple will be twice as bad as it would be if the ADJ pin were to be bypassed to ground with a properly selected capacitor. OUTPUT VOLTAGE The LX857/87A ICs develop a 1.25V reference voltage between the output and the adjust terminal (See Figure 2). By placing a resistor, R1, between these two terminals, a constant current is caused to flow through R1 and down through R2 to set the overall output voltage. Normally this current is the specified minimum load current of 10mA. Because IADJ is very small and constant when compared with the current through R1, it represents a small error and can usually be ignored.
Copyright (c) 2000 Rev. 2.0a, 2005-10-25
ADJ
R1
Connect R1 to Case of Regulator
APPLICATIONS APPLICATIONS
R2
Connect R2 to Load
RL
FIGURE 3 - CONNECTIONS FOR BEST LOAD REGULATION
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LX8587X-xx
TM (R)
3A Low Dropout Positive Regulators
PRODUCTION DATA SHEET
APPLICATION NOTES (CONTINUED)
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LOAD REGULATION (continued) Even when the circuit is configured optimally, parasitic resistance can be a significant source of error. A 100 mil. wide PC trace built from 1 oz. copper-clad circuit board material has a parasitic resistance of about 5 milliohms per inch of its length at room temperature. If a 3-terminal regulator used to supply 2.50 volts is connected by 2 inches of this trace to a load which draws 5 amps of current, a 50 millivolt drop will appear between the regulator and the load. Even when the regulator output voltage is precisely 2.50 volts, the load will only see 2.45 volts, which is a 2% error. It is important to keep the connection between the regulator output pin and the load as short as possible, and to use wide traces or heavy-gauge wire. The minimum specified output capacitance for the regulator should be located near the regulator package. If several capacitors are used in parallel to construct the power system output capacitance, any capacitors beyond the minimum needed to meet the specified requirements of the regulator should be located near the sections of the load that require rapidly-changing amounts of current. Placing capacitors near the sources of load transients will help ensure that power system transient response is not impaired by the effects of trace impedance. To maintain good load regulation, wide traces should be used on the input side of the regulator, especially between the input capacitors and the regulator. Input capacitor ESR must be small enough that the voltage at the input pin does not drop below VIN(MIN) during transients.
Example Given:
= 5V VIN VOUT = 2.8V 5.0A IOUT = TA = 50C 2.7C/W for TO-220 RJT = 300 ft/min airflow available Proper Heat Sink to keep IC's junction temperature below 125C.**
Find:
Solution: The junction temperature is:
TJ = PD (R JT + R CS + R SA ) + TA
where: PD RJT RCS Dissipated power. Thermal resistance from the junction to the mounting tab of the package. Thermal resistance through the interface between the IC and the surface on which it is mounted. (1.0C/W at 6 in-lbs mounting screw torque). Thermal resistance from the mounting surface to ambient (thermal resistance of the heat sink). Heat Sink Temperature.
RSA TS

V() = VOUT + VDROPOUT(MAX)
where: VIN(MIN) the lowest allowable instantaneous voltage at the input pin. VOUT the designed output voltage for the power supply system. VDROPOUT(MAX) the specified dropout voltage for the installed regulator.
TJ RJT
TC
TS RCS
TA RSA
First, find the maximum allowable thermal resistance of the heat sink:
R SA =
TJ - TA - (R JT + R CS ) PD
THERMAL CONSIDERATIONS The LX8587/87A regulators have internal power and thermal limiting circuitry designed to protect each device under overload conditions. For continuous normal load conditions, however, maximum junction temperature ratings must not be exceeded. It is important to give careful consideration to all sources of thermal resistance from junction to ambient. This includes junction to case, case to heat sink interface, and heat sink thermal resistance itself. Junction-to-case thermal resistance is specified from the IC junction to the back surface of the case directly opposite the die. This is the lowest resistance path for heat flow. Proper mounting is required to ensure the best possible thermal flow from this area of the package to the heat sink. Thermal compound at the case to heat sink interface is strongly recommended. If the case of the device must be electrically isolated, a thermally conductive spacer can be used, as long as its added contribution to thermal resistance is considered. Note that the case of all devices in this series is electrically connected to the output.
Copyright (c) 2000 Rev. 2.0a, 2005-10-25
PD = (VIN(MAX) - VOUT ) I OUT = (5.0V - 2.8V ) x 5.0A PD = 11.0W
R SA = 125C - 50C - (2.7C/W + 1.0C/W) (5.0V - 2.8V) * 5.0A R SA = 3.1C/W
APPLICATIONS APPLICATIONS
Next, select a suitable heat sink. The selected heat sink must have RSA < 3.1C/W. Thermalloy heatsink 6296B has RSA = 3.0C/W with 3000ft/min air flow. Finally, verify that junction temperature remains within specification using the selected heat sink:
TJ = 11W(2.7C/W + 1.0C/W + 3.0C/W) + 50C TJ = 124C
** Although the device can operate up to 150C junction, it is recommended for long term reliability to keep the junction temperature below 125C whenever possible.
Microsemi
Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
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LX8587X-xx
TM (R)
3A Low Dropout Positive Regulators
PRODUCTION DATA SHEET
TYPICAL APPLICATIONS
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(Note A)
VIN
(Note A) 10F +
IN
OUT
R1 121 1%
VIN
IN
+
OUT
R1 121 1% +
VOUT**
C2 100F
VOUT
C1* 10F
ADJ
150F
ADJ
R2 365 1%
+
C1 10F*
R2 1k
* C1 improves ripple rejection. XC should be R1 at ripple frequency.
FIGURE 5 - 1.2V - 8V ADJUSTABLE REGULATOR
FIGURE 4 - IMPROVING RIPPLE REJECTION
* Needed if device is far from filter capacitors.
* *VOUT = 1.25V 1 +

R2 R1
VIN
(note A) +
IN
OUT
121 1%
+
5V
10F
ADJ
1k 2N3904
100F 365 1%
VIN
10F Tantalum or 100F Aluminum
IN
OUT
3.3V
Min. 15F Tantalum or 100F Aluminum capacitor. May be increased without limit. ESR must be less than <400m.
TTL Output
ADJ
1k
FIGURE 7 - FIXED 3.3V OUTPUT REGULATOR
FIGURE 6 - 5V REGULATOR WITH SHUTDOWN
APPLICATIONS APPLICATIONS
Note A:
VIN(MIN) = (Intended VOUT ) + VDROPOUT(MAX)
Copyright (c) 2000 Rev. 2.0a, 2005-10-25
Microsemi
Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 8
LX8587X-xx
TM (R)
3A Low Dropout Positive Regulators
PRODUCTION DATA SHEET
PACKAGE DIMENSIONS
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P
3-Pin Plastic TO-220
B S F Q T
Dim
U
A
1
2
3
H R
C
K D
L G N
J
A B C D F G H J K L N Q R S T U
MILLIMETERS MIN MAX 14.22 15.88 9.65 10.67 3.56 4.83 0.51 1.14 3.53 4.09 2.54 BSC 6.35 0.30 1.14 12.70 14.73 1.14 1.27 5.08 TYP 2.54 3.05 2.03 2.92 1.14 1.40 5.84 6.86 0.508 1.14
INCHES MIN MAX 0.560 0.625 0.380 0.420 0.140 0.190 0.020 0.045 0.139 0.161 0.100 BSC 0.250 0.012 0.045 0.500 0.580 0.045 0.050 0.200 TYP 0.100 0.120 0.080 0.115 0.045 0.055 0.230 0.270 0.020 0.045
DD
3-Pin Plastic TO-263
A I D C
Dim A B C D E F G H I J K M N
B K M N
H F G E
0 -8
J
Seating Plane
MILLIMETERS MIN MAX 10.03 10.67 8.51 9.17 4.19 4.59 1.14 1.40 0.330 0.51 1.19 1.34 2.41 2.66 2.29 2.79 - 1.65 0 0.25 14.60 15.87 7 3
INCHES MIN MAX 0.395 0.420 0.335 0.361 0.165 0.181 0.045 0.055 0.013 0.020 0.047 0.053 0.095 0.104 0.090 0.110 - 0.065 0 0.010 0.575 0.625 7 3
MECHANICALS MECHANICALS
Note: Dimensions do not include mold flash or protrusions; these shall not exceed 0.155mm(.006") on any side. Lead dimension shall not include solder coverage.
Copyright (c) 2000 Rev. 2.0a, 2005-10-25
Microsemi
Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
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LX8587X-xx
TM (R)
3A Low Dropout Positive Regulators
PRODUCTION DATA SHEET
PACKAGE DIMENSIONS
WWW .Microsemi .C OM
DT
3-Pin Plastic TO-252
P J U
Dim A B C D E F G H I J K L M N O P Q R U V W X
G N W L A
F Q O V 0.23
H R
M C D B K
E
X
I
MILLIMETERS MIN MAX 6.47 6.73 5.97 6.23 2.16 2.42 0.68 0.94 0.38 0.64 0.63 0.89 2.16 2.42 0.84 1.10 0.89 1.15 2.44 2.70 9.55 9.81 5.20 5.46 7.0 0.51 0.77 0.51 0.77 4.19 4.45 0.76 1.02 0.48 0.74 0.51 0.77 45 1.44 1.70 0 0.10
INCHES MIN MAX 0.255 0.265 0.235 0.245 0.085 0.095 0.027 0.037 0.015 0.025 0.025 0.035 0.085 0.095 0.033 0.043 0.035 0.045 0.096 0.106 0.376 0.386 0.205 0.215 7.0 0.020 0.030 0.020 0.030 0.165 0.175 0.030 0.040 0.019 0.029 0.020 0.030 45 0.057 0.067 0 0.004
MECHANICALS MECHANICALS
Copyright (c) 2000 Rev. 2.0a, 2005-10-25
Microsemi
Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 10
LX8587X-xx
TM (R)
3A Low Dropout Positive Regulators
PRODUCTION DATA SHEET
NOTES
WWW .Microsemi .C OM
NOTES NOTES
PRODUCTION DATA - Information contained in this document is proprietary to LinFinity and is current as of publication date. This document may not be modified in any way without the express written consent of LinFinity. Product processing does not necessarily include testing of all parameters. LinFinity reserves the right to change the configuration and performance of the product and to discontinue product at any time.
Copyright (c) 2000 Rev. 2.0a, 2005-10-25
Microsemi
Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 11

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