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LT1083/84/85 Fixed 3A, 5A, 7.5A Low Dropout Positive Fixed Regulators
FEATURES
s s s s s s s s
DESCRIPTION
The LT1083 series of positive adjustable regulators are designed to provide 3A, 5A and 7.5A with higher efficiency than currently available devices. All internal circuitry is designed to operate down to 1V input to output differential and the dropout voltage is fully specified as a function of load current. Dropout is guaranteed at a maximum of 1.5V at maximum output current, decreasing at lower load currents. On-chip trimming adjusts the output voltage to 1%. Current limit is also trimmed, minimizing the stress on both the regulator and power source circuitry under overload conditions. The 1083 series devices are pin compatible with older three-terminal regulators. A 10F output capacitor is required on these new devices; however, this is usually included in most regulator designs. Unlike PNP regulators, where up to 10% of the output current is wasted as quiescent current, the LT1083 quiescent current flows into the load, increasing efficiency.
Three-Terminal 3.3V, 3.6V, 5V and 12V Output Current of 3A, 5A or 7.5A Operates Down to 1V Dropout Guaranteed Dropout Voltage at Multiple Current Levels Line Regulation: 0.015% Load Regulation: 0.1% 100% Thermal Limit Functional Test Adjustable Versions Available
APPLICATIONS
s s s s
High Efficiency Linear Regulators Post Regulators for Switching Supplies Constant Current Regulators Battery Chargers
DEVICE LT1083 LT1084 LT1085 OUTPUT CURRENT* 7.5 Amps 5.0 Amps 3.0 Amps
*For a 1.5A low dropout regulator see the LT1086 data sheet.
TYPICAL APPLICATION
5V, 7.5A Regulator
INPUT/OUTPUT VOLTAGE DIFFERENTIAL (V)
Dropout Voltage vs Output Current
2
VIN 6.5V
LT1083-5
5V AT 7.5A
+
10F
+
22F* TANTALUM
*REQUIRED FOR STABILITY
1
LT1083/4/5 TA01
0
0
U
U
U
IFULL LOAD/2 OUTPUT CURRENT (A)
IFULL LOAD
1083/4/5 TA02
1
LT1083/84/85 Fixed
ABSOLUTE MAXIMUM RATINGS
Power Dissipation............................... Internally Limited Input Voltage (Note 1) ............................................. 30V Operating Input Voltage 3.3V, 3.6V Devices ............................................ 20V 5V Devices ........................................................ 20V 12V Devices ...................................................... 25V Operating Junction Temperature Range "C" Grades Control Section ............................... 0C to 125C Power Transistor ............................. 0C to 150C "M" Grades Control Section ........................... -55C to 150C Power Transistor ......................... -55C to 200C Storage Temperature Range ................. - 65C to 150C Lead Temperature (Soldering, 10 sec).................. 300C
Note 1: Although the devices maximum operating voltage is limited, (20V for a 3V, 5V device, and 25V for a 12V device) the devices are guaranteed to withstand transient input voltages up to 30V. For input voltages greater than the maximum operating input voltage some degradation of specifications will occur. For input/output voltage differentials greater than 15V, a minimum external load of 5mA is required to maintain regulation.
PRECONDITIONING
100% Thermal Limit Functional Test.
PACKAGE/ORDER INFORMATION
VIN 2 CASE IS OUTPUT
ORDER PART NUMBER LT1083CK-5 LT1083CK-12 LT1083MK-5 LT1083MK-12 LT1084CK-5 LT1084CK-12 LT1084MK-5 LT1084MK-12 LT1085CK-5 LT1085CK-12 LT1085MK-5 LT1085MK-12
TAB IS OUTPUT
FRONT VIEW
3 2 1 P PACKAGE 3-LEAD TO-3P PLASTIC
1 GND K PACKAGE 2-LEAD TO-3 METAL CAN
JA = 35C/W
FRONT VIEW
JA = 45C/W
FRONT VIEW 3 TAB IS OUTPUT 2 1 M PACKAGE 3-LEAD PLASTIC DD VIN VOUT GND
TAB IS OUTPUT
3 2 1 T PACKAGE 3-LEAD PLASTIC TO-220
VIN VOUT GND
JA = 50C/W
LT1084CT-3.3 LT1084CT-5 LT1084CT-12 LT1085CT-3.3 LT1085CT-3.6 LT1085CT-5 LT1085CT-12
JA = 30C/W* * WITH PACKAGE SOLDERED TO 0.52IN2 COPPER AREA OVER BACKSIDE GROUND PLANE OR INTERNAL POWER PLANE. JA CAN VARY FROM 20C/W TO > 40C/W DEPENDING ON MOUNTING TECHNIQUE.
Consult factory for Industrial grade parts.
ELECTRICAL CHARACTERISTICS
PARAMETER Output Voltage CONDITIONS LT1084-3.3 LT1085-3.3 LT1085-3.6 IOUT = 0mA, TJ = 25C, VIN = 8V (K Package Only) 0 IOUT 5A, 4.8V VIN 15V (Note 8) VIN = 5V, IOUT = 0mA, TJ = 25C (K Package Only) 4.8V VIN 15V, 0 IOUT 3A (Note 8) VIN = 5V, IOUT = 0mA, TJ = 25C (K Package Only) 5V VIN 15V, 0 IOUT 3A (Note 8) 5V VIN 15V, 0 IOUT 3A, TJ 0C (Note 8) q q q MIN 3.270 3.235 3.270 3.235 3.564 3.500 3.528 TYP 3.300 3.300 3.300 3.300 3.600 MAX 3.330 3.365 3.330 3.365 3.636 3.672 3.672 UNITS V V V V V V V
2
UU
U
U
U
W
WW U
W
ORDER PART NUMBER
VIN VOUT GND
LT1083CP-5 LT1083CP-12 LT1084CP-5 LT1084CP-12
LT1085CM-3.3 LT1085CM-3.6
LT1083/84/85 Fixed
ELECTRICAL CHARACTERISTICS
PARAMETER Output Voltage CONDITIONS LT1085-3.6 5V VIN 15V, 0 IOUT 2.5A (Note 8) VIN = 4.75V, IOUT = 3A, TJ 0C VIN = 4.75V, IOUT = 2.5A, TJ 0C VIN = 4.75V, IOUT = 1.5A, TJ > 0C IOUT = 0mA, TJ = 25C, VIN = 8V (K Package Only) 0 IOUT IFULLOAD, 6.5V VIN 20V (Notes 3, 5, 6, 8) IOUT = 0mA, TJ = 25C, VIN = 15V (K Package Only) 0 IOUT IFULLOAD, 13.5V VIN 25V (Notes 3, 5, 6, 8) IOUT = 0mA, TJ = 25C, 4.8V VIN 15V 4.8V VIN 15V, IOUT = 0mA, TJ= 25C q LT1085-3.6 LT1083/4/5-5 LT1083/4/5-12 Load Regulation LT1084-3.3 LT1085-3.3 LT1085-3.6 LT1083/4/5-5 LT1083/4/5-12 Dropout Voltage 4.8V VIN 15V, IOUT = 0mA, TJ= 25C q IOUT = 0mA, TJ = 25C, 6.5V VIN 20V (Notes 1, 2) q IOUT = 0mA, TJ = 25C, 13.5V VIN 25V (Notes 1, 2) q VIN = 5V, 0 IOUT 5A, TJ = 25C q VIN = 5V, 0 IOUT 3A, TJ = 25C q VIN = 5.25V, 0 IOUT 3A, TJ = 25C q VIN = 8V, 0 IOUT IFULLLOAD, TJ = 25C (Notes 1, 2, 3, 5) q VIN = 15V, 0 IOUT IFULLLOAD, TJ = 25C (Notes 1, 2, 3, 5) q q q q q q q q q q q q q q q q q q q MIN 3.528 3.350 3.450 3.528 4.950 4.900 11.880 11.760 TYP MAX 3.672 3.672 3.672 3.672 5.050 5.100 12.120 12.240 6 6 6 6 6 6 10 10 25 25 15 20 15 20 15 20 20 35 36 72 1.5 1.5 1.5 1.5 UNITS V V V V V V V V mV mV mV mV mV mV mV mV mV mV mV mV mV mV mV mV mV mV mV mV V V V V A A A A A A A A mA mA mA mA mA %/W %/W %/W dB
LT1083/4/5-5 LT1083/4/5-12 Line Regulation LT1084-3.3 LT1085-3.3
q
Current Limit
Quiescient Current
Thermal Regulation
Ripple Rejection
LT1084/5-3.3 VOUT = 33mV, IOUT = IFULL LOAD (Notes 4, 5) LT1085-3.6 VOUT = 36mV, IOUT = IFULL LOAD (Notes 4, 5) LT1083/4/5-5 VOUT = 50mV, IOUT = IFULL LOAD (Notes 4, 5) LT1083/4/5-12 VOUT = 120mV, IOUT = IFULL LOAD (Notes 4, 5) LT1083-5 VIN = 10V LT1083-12 VIN = 17V LT1084-3.3 VIN = 8V LT1084-5 VIN = 10V LT1084-12 VIN = 17V LT1085-3.3/3.6 VIN = 8V LT1085-5 VIN = 10V LT1085-12 VIN = 17V LT1084-3.3 VIN = 18V LT1085-3.3 VIN = 18V LT1085-3.6 VIN = 18V LT1083/4/5-5 VIN 20V LT1083/4/5-12 VIN 25V LT1083-5/12 TA = 25C, 30ms pulse LT1084-3.3/5/12 LT1085-3.3/3.6/5/12 f = 120Hz, COUT = 25F Tantalum, IOUT = IFULLLOAD LT1084-3.3 f = 120Hz, COUT = 25F Tantalum, IOUT = 5A, VIN = 6.3V
8.0 8.0 5.5 5.5 5.5 3.2 3.2 3.2
5.000 5.000 12.000 12.000 0.5 1.0 0.5 1.0 0.5 1.0 0.5 1.0 1.0 2.0 3 7 3 7 3 7 5 10 12 24 1.3 1.3 1.3 1.3 9.5 9.5 6.5 6.5 6.5 4.0 4.0 4.0 5.0 10.0 5.0 10.0 5.0 10.0 5.0 10.0 5.0 10.0 0.002 0.010 0.003 0.015 0.004 0.020 72
q
60
3
LT1083/84/85 Fixed
ELECTRICAL CHARACTERISTICS
PARAMETER Ripple Rejection CONDITIONS LT1085-3.3 LT1085-3.6 LT1083/4/5-5 LT1083/4/5-12 f = 120Hz, COUT = 25F Tantalum, VIN = 6.3V, IOUT = 3A f = 120Hz, COUT = 25F Tantalum, VIN = 6.6V, IOUT = 3A VIN = 8V (Note 5) VIN = 15V (Note 5) q q q q q MIN 60 60 60 54 TYP 72 72 68 60 0.5 0.03 0.003 0.6/1.6 0.5/1.6 0.75/2.3 0.65/2.3 0.65/2.7 0.9/3.0 0.7/3.0 0.7/3.0 MAX UNITS dB dB dB dB % % % C/W C/W C/W C/W C/W C/W C/W C/W
Temperature Stability Long Term Stability RMS Output Noise (% of VOUT) Thermal Resistance Junctrion-to-Case
TA = 125C, 1000 Hrs. TA = 25C, 10Hz = f 10kHz Control Circuitry/Power Transistor (See Applications Information) LT1083 K Package P Package LT1084 K Package P Package T Package LT1085 K Package T Package DD Package
1.0
The q denotes the specifications which apply over the full operating temperature range. Note 1: See thermal regulation specifications for changes in output voltage due to heating effects. Load and line regulation are measured at a constant junction temperature by low duty cycle pulse testing. Note 2: Line and load regulation are guaranteed up to the maximum power dissipation (60W for the LT1083, 45W for the LT1084 (K, P), 30W for the LT1084 (T) and 30W for the LT1085). Power dissipation is determined by the input/output differential and the output current. Guaranteed maximum power dissipation will not be available over the full input/output range. Note 3: IFULL LOAD is defined in the current limit curves. The IFULLLOAD curve is defined as the minimum value of current limit as a function of
input to output voltage. Note that the 60W power dissipation for the LT1083 (45W for the LT1084 (K, P), 30W for the LT1084 (T), 30W for the LT1085) is only achievable over a limited range of input to output voltage. Note 4: Dropout voltage is specified over the full output current range of the device. Test points and limits are shown on the Dropout Voltage curve. Note 5: For LT1083 IFULL LOAD is 5A for - 55C TJ - 40C and 7.5A for TJ - 40C. Note 6: 1.7V (VIN - VOUT) 25V for LT1084 at - 55C TJ - 40C. Note 7: Dropout voltage 1.7V maximum for LT1084 at - 55 TJ - 40C. Note 8: Full load current is not available at all input-output voltages. See Notes 2,3,5.
TYPICAL PERFORMANCE CHARACTERISTICS
LT1083 Dropout Voltage
MINIMUM INPUT/OUTPUT DIFFERENTIAL (V)
2 INDICATES GUARANTEED TEST POINT SHORT-CIRCUIT CURRENT (A) -40C TJ 150C 0C TJ 125C 12 10 8 6 4 2 0 0 20 30 15 25 5 10 INPUT/OUTPUT DIFFERENTIAL (V) 35 -55C IFULL LOAD
GUARANTEED
25C 150C
OUTPUT VOLTAGE DEVIATION (%)
1
TJ = 150C TJ = 25C TJ = -55C
0
0
1
2
345678 OUTPUT CURRENT (A)
LT1083/4/5 FIXED G01
4
UW
9
LT1083 Short-Circuit Current
0.10
LT1083 Load Regulation
I = 7.5A 0.05 0 -0.05 -0.10 -0.15 -0.20 -50 -25
10
0
25 50 75 100 125 150 TEMPERATURE (C)
LT1083/4/5 FIXED G03
LT1083/4/5 FIXED G02
LT1083/84/85 Fixed TYPICAL PERFORMANCE CHARACTERISTICS
LT1084 Dropout Voltage
MINIMUN INPUT/OUTPUT DIFFERENTIAL (V)
2 INDICATES GUARANTEED TEST POINT
SHORT-CIRCUIT CURRENT (A)
-55C TJ 150C 0C TJ 125C
OUTPUT VOLTAGE DEVIATION (%)
1 TJ = -55C TJ = 150C TJ = 25C
0 0 1 3 4 2 OUTPUT CURRENT (A) 5 6
LT1083/4/5 FIXEDG04
LT1085 Dropout Voltage
MINIMUM INPUT/OUTPUT DIFFERENTIAL (V)
2 INDICATES GUARANTEED TEST POINT -55C TJ 150C 0C TJ 125C
SHORT-CIRCUIT CURRENT (A)
5 4 3 -55C 2 1 0 IFULL LOAD GUARANTEED 25C 150C
OUTPUT VOLTAGE DEVIATION (%)
1 TJ = 25C TJ = 150C
TJ = -55C
0 0 2 3 1 OUTPUT CURRENT (A) 4
LT1083/4/5 FIXED G07
LT1083/4/5-5 Ripple Rejection
80 70 VRIPPLE 3VP-P VRIPPLE 0.5VP-P
RIPPLE REJECTION (dB)
RIPPLE REJECTION (dB)
60 50 40 30 20 IOUT = IFULL LOAD 10 0 10 100
(VIN - VOUT) 3V (VIN - VOUT) VDROPOUT
80 70 60 50 40 30 20 10 fR = 20kHz VRIPPLE 0.5VP-P
fR = 120Hz VRIPPLE 3VP-P
OUTPUT VOLTAGE CHANGE (%)
1k 10k FREQUENCY (Hz)
UW
1083/4/5 FIXED G10
LT1084 Short Circuit Current
10 9 8 7 6 5 4 3 2 1 0 0 20 15 10 25 30 5 INPUT/OUTPUT DIFFERENTIAL (V) 35 IFULL LOAD GUARANTEED -55C 150C 25C
0.05 0 -0.05 -0.10 -0.15 0.10
LT1084 Load Regulation
I = 5A
-0.20 -50 -25
0
25 50 75 100 125 150 TEMPERATURE (C)
LT1083/4/5 FIXED G06
LT1083/4/5 FIXED G05
LT1085 Short-Circuit Current
6
0.10
LT1085 Load Regulation
I = 3A 0.05 0 -0.05 -0.10 -0.15 -0.20 -50 -25
0
20 30 15 25 5 10 INPUT/OUTPUT DIFFERENTIAL (V)
35
0
25 50 75 100 125 150 TEMPERATURE (C)
LT1083/4/5 FIXED G09
LT1083/4/5 FIXED G08
LT1083/4/5-5 Ripple Rejection vs Current
100 90
1.0 2.0
Temperature Stability
0
-1.0
100k
0 0 0.8 0.2 0.6 0.4 OUTPUT CURRENT (0 TO IFULL LOAD) 1.0
-2.0 -50 -25
0
25 50 75 100 125 150 TEMPERATURE (C)
LT1183/4/5 FIXED G12
1083/4/5 FIXED G11
5
LT1083/84/85 Fixed TYPICAL PERFORMANCE CHARACTERISTICS
LT1083/4/5-12 Ripple Rejection
80 70 VRIPPLE 3VP-P VRIPPLE 0.5VP-P
RIPPLE REJECTION (dB)
RIPPLE REJECTION (dB)
60 50 40 30 20 IOUT = IFULL LOAD 10 0 10 100 1k 10k FREQUENCY (Hz) 100k (VIN - VOUT) 3V
POWER (W)
(VIN - VOUT) VDROPOUT
LT1084 Maximum Power Dissipation*
60 50 LT1084MK 40 50
POWER (W)
POWER (W)
30 LT1084CT 20 10 0 LT1084CK LT1084CP
50 60 70 80 90 100 110 120 130 140 150 CASE TEMPERATURE (C) * AS LIMITED BY MAXIMUM JUNCTION TEMPERATURE
LT1083/4/5 FIXED G16
6
UW
1083/4/5 FIXED G13
LT1083/4/5-12 Ripple Rejection vs Current
100 90 80 70 60 50 40 30 20 10 0 0 0.8 0.2 0.6 0.4 OUTPUT CURRENT (0 TO IFULL LOAD) 1.0 fR = 20kHz VRIPPLE 0.5VP-P fR = 120Hz VRIPPLE 3VP-P
LT1083 Maximum Power Dissipation*
100 90 80 70 60 50 40 30 20 10 0 LT1083CK LT1083CP LT1083MK
1083/4/5 FIXED G14
50 60 70 80 90 100 110 120 130 140 150 CASE TEMPERATURE (C) * AS LIMITED BY MAXIMUM JUNCTION TEMPERATURE
LT1083/4/5 FIXED G15
LT1085 Maximum Power Dissipation*
40 LT1085MK
30
20 LT1085CT 10 LT1085CK 0 50 60 70 80 90 100 110 120 130 140 150 CASE TEMPERATURE (C) * AS LIMITED BY MAXIMUM JUNCTION TEMPERATURE
LT1083/4/5 FIXED G17
LT1083/84/85 Fixed
BLOCK DIAGRAM
APPLICATIONS INFORMATION
The LT1083 family of three-terminal regulators are easy to use and have all the protection features that are expected in high performance voltage regulators. They are short circuit protected, have safe area protection as well as thermal shutdown to turn off the regulator should the temperature exceed about 165C. These regulators offer lower dropout voltage and more precise reference tolerance. Further, the reference stability with temperature is improved over older types of regulators. The only circuit difference between using the LT1083 family and older regulators is that they require an output capacitor for stability. Stability The circuit design used in the LT1083 family requires the use of an output capacitor as part of the device frequency compensation. For all operating conditions, the addition of 150F aluminum electrolytic or a 22F solid tantalum on the output will ensure stability. Normally capacitors much smaller than this can be used with the LT1083. Many different types of capacitors with widely varying characteristics are available. These capacitors differ in capacitor tolerance (sometimes ranging up to 100%), equivalent series resistance, and capacitance temperature coefficient. The 150F or 22F values given will ensure stability. Normally, capacitor values on the order of 100F are used in the output of many regulators to ensure good transient response with heavy load current changes. Output capacitance can be increased without limit and larger values of output capacitance further improve stability and transient response of the LT1083 regulators. Another possible stability problem that can occur in monolithic IC regulators is current limit oscillations. These can occur because in current limit the safe area protection exhibits a negative impedance. The safe area protection decreases the current limit as the input-to-output voltage increases.That is the equivalent of having a negitive resistance since increasing voltage causes current to decrease. Negitive resistance during current limit is not unique to the LT1083 series and has been present on all power IC regulators. The value of negative resistance is a function of how fast the current limit is folded back as input-to-
U
W
W
VIN
+ -
THERMAL LIMIT
GND
LT1083/4/5 BD
U
U
7
LT1083/84/85 Fixed
APPLICATIONS INFORMATION
output voltage increases. This negative resistance can react with capacitors or inductors on the input to cause oscillations during current limiting. Depending on the value of series resistance, the overall circuitry may end up unstable. Since this is a system problem, it is not necessarily easy to solve; however it does not cause any problems with the IC regulator and can usually be ignored. Protection Diodes In normal operation the LT1083 family does not need any protection diodes, The internal diode between the input and the output pins of the LT1083 family can handle microsecond surge currents of 50A to 100A. Even with large output capacitances it is very difficult to get those values of surge current in normal operation. Only with high value output capacitors, such as 1000F to 5000F and with the input pin instantaneously shorted to ground, can damage occur. A crowbar circuit at the input of the LT1083 can generate those kinds of currents and a diode from output-to-input is then recommended. Normal power supply cycling or even plugging and unplugging in the system will not generate currents large enough to do any damage.
D1 1N4002 (OPTIONAL)
VIN
IN
LT1083 ADJ
OUT
VOUT
+
COUT 150F
LT1083/4/5 AI01
Overload Recovery Like any of the IC power regulators, the LT1083 has safe area protection. The safe area protection decreases the current limit as input-to-output voltage increases and keeps the power transistor inside a safe operating region for all values of input-to-output voltage. The LT1083 protection is designed to provide some output current at all values of input-to-output voltage up to the device breakdown. When power is first turned on, as the input voltage rises, the output follows the input, allowing the regulator to start up into very heavy loads. During the start-up, as the input
8
U
W
U
U
voltage is rising, the input-to-output voltage differential remains small allowing the regulator to supply large output currents. With high input voltage a problem can occur wherein removal of an output short will not allow the output voltage to recover. Older regulators such as the 7800 series, also exhibited this phenomenon so it is not unique to the LT1083. The problem occurs with a heavy output load when the input voltage is high and the output voltage is low, such as immediately after a removal of a short. The load line for such a load may intersect the output current curve at two points. If this happens there are two stable output operating points for the regulator. With this double intersection the power supply may need to be cycled down to zero and brought up again to make the output recover. Ripple Rejection In applications that require improved ripple rejection the LT1083 series adjustable regulators should be used. With LT1083 series adjustable regulators the addition of a bypass capacitor from the adjust pin to ground will reduce output ripple by the ratio of VOUT/1.25V. See LT1083 series adjustable regulator data sheet. Load Regulation Because the LT1083 is a three-terminal device, it is not possible to provide true remote load sensing. Load regulation will not be limited by the resistance of the wire connecting the regulator to the load. The data sheet specification for the load regulation is measured at the bottom of the package. Negative side sensing is a true Kelvin connection, with the ground pin of the device returned to the negative side of the load. Thermal Considerations The LT1083 series of regulators have internal power and thermal limiting circuitry designed to protect the 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, caseto-heat sink interface, and heat sink resistance itself. New
LT1083/84/85 Fixed
APPLICATIONS INFORMATION
thermal resistance specifications have been developed to more accurately reflect device temperature and ensure safe operating temperatures. The data section for these new regulators provides a separate thermal resistance and maximum junction temperature for both the Control Section and the Power Section. Previous regulators, with a single junction-to-case thermal resistance specification, used an average of the two values provided here and therefore could allow excessive junction temperatures under certain conditions of ambient temperature and heat sink resistance. To avoid this possibility, calculations should be made for both sections to ensure that both thermal limits are met. Junction-to-case thermal resistance is specified from the IC junction to the bottom of the case directly below 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 electronically 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 electronically connected to the ouput. For example, using a LT1083-5CK (TO-3, Commercial) and assuming: VIN(max continuous) = 9V, VOUT = 5V, IOUT = 6A, TA = 75C HEAT SINK = 1C/W, CASE-TO-HEAT SINK = 0.2C/W for K package with thermal compound. Power dissipation under these conditions is equal to: PD = (VIN - VOUT) (IOUT) = 24W Junction temperature will be equal to: TJ = TA + PD (HEAT SINK + CASE-TO-HEAT SINK + JC) For the Control Section: TJ = 75C + 24W (1C/W + 0.2C/W + 0.6C/W) = 118C 118C < 125C = TJMAX (Control Section Commercial Range) For the Power Transistor: TJ = 75C + 24W (1C/W + 0.2C/W + 1.6C/W) = 142C 142C < 150C = TJMAX (Power Transistor Commercial Range) In both cases the junction temperature is below the maximum rating for the respective sections, ensuring reliable operation.
TYPICAL APPLICATIONS
High Efficiency Regulator
28V INPUT 10k 1mH IN LT1083-5 OUT GND 470 1N914 OUTPUT
1k
1M
LT1011
U
W
U
U
U
+
10,000F MR1122 28V
4N28
+ -
1N914
10k
10k
28V
LT1083/4/5 TA03
9
LT1083/84/85 Fixed
TYPICAL APPLICATIONS
Paralleling Regulators
VIN
T1 TRIAD F-269U
C30B
20 110VAC 20 3
C30B 1N914 1N4003 1N4003 16k* 15V 16k*
1F
82k
10k 1N4148
* 1% FILM RESISTOR L-DALE TO-5 TYPE T2-STANCOR 11Z-2003
REGULATOR WITH SCR PREREGULATOR TO LOWER POWER DISSIPATION. ABOUT 1.7V DIFFERENTIAL IS MAINTAINED ACROSS THE LT1083 INDEPENDENT OF LOAD CURRENT.
10
U
IN
LT1083-5 OUT GND
2 FEET #18 WIRE*
VOUT = 5V IOUT = 0A TO 15A 0.015 IN LT1083-5 OUT GND *THE #18 WIRE ACTS AS BALLAST RESISTANCE INSURING CURRENT SHARING BETWEEN BOTH DEVICES
LT1083/4/5 TA04
7.5A Regulator
L 1MH IN T2 4 2 LT1083-12 OUT GND LT1004-1.2
12V 0A TO 7.5A
1N4003
+ C1
50,000F
+
100F
1
560
15k 2
8
-15V 4 7
+
LT1011
200k
11k*
3
-
1 15V
0.1F NC 100pF 2N3904 3 8 1 10k
-15V 4 7
8
- +
1
LT1011 2 6
+ -
4 -15V
3
LM301A 2 11k* 7 15V
15k
15V 1F
LT1083/4/5 TA05
LT1083/84/85 Fixed
TYPICAL APPLICATIONS
Adjusting Output Voltage Regulator with Reference
VIN > 12V
LT1085-5
+
10F
+
10F*
1k
LT1083/4/5 TA06
*OPTIONAL IMPROVES RIPPLE REJECTION
VIN
FLOATING INPUT
LT1083/4/5 TA08
VIN
Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
U
5V to 10V
VIN > 11.5V
LT1085-5
10V
+
100F
+
10F 5VOUT LT1029
+
100F
LT1083/4/5 TA07
Low Dropout Negative Supply
IN
LT1084-12 OUT GND
+
10,000F
+
100F
VOUT = -12V
Battery Backed Up Regulated Supply
LT1084-5
5.2V LINE 5.0V BATTERY
+
10F 50 SELECT FOR CHARGE RATE LT1084-5
6.5V
+
10F
+
100F
LT1083/4/5 TA09
11
LT1083/84/85 Fixed
PACKAGE DESCRIPTION
M Package 3-Lead Plastic DD
0.060 (1.524) 0.401 0.015 (10.185 0.381) 15 TYP +0.012 0.331 -0.020
0.175 0.008 (4.445 0.203)
(
+0.305 8.407 -0.508
)
0.100 0.010 (2.5402 0.254) 0.050 0.008 (1.270 0.203)
0.059 (1.499) TYP
(
+0.012 0.143 -0.020
+0.305 3.632 -0.508
)
0.022 0.005 (0.559 0.127)
K Package 2-Lead TO-3 Metal Can
0.620 - 0.64O (15.75 - 16.26)
0.320 - 0.350 (8.13 - 8.89)
0.760 - 0.775 (19.30 - 19.69) 0.060 - 0.135 (1.524 - 3.429)
0.420 - 0.480 (10.67 - 12.19)
0.038 - 0.043 (0.965 - 1.09)
1.177 - 1.197 (29.90 - 30.40) 0.067 - 0.077 (1.70 - 1.96) 0.210 - 0.220 (5.33 - 5.59) 0.152 - 0.161 (3.86 - 4.09) DIA 0.167 - 0.177 (4.24 - 4.49) R TYP 0.495 - 0.525 (12.57 - 13.34)
K2 0592
0.425 - 0.435 (10.80 - 11.05)
0.655 - 0.675 (16.64 - 17.15)
12
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7487
(408) 432-1900 q FAX: (408) 434-0507 q TELEX: 499-3977
U
Dimension in inches (millimeters) unless otherwise noted.
T Package 3-Lead Plastic TO-220
0.079 - 0.135 (2.007 - 3.429) 0.380 - 0.420 (9.652 - 10.668) 0.139 - 0.153 (3.531 - 3.886) DIA 0.169 - 0.185 (4.293 - 4.699) 0.035 - 0.055 (0.889 - 1.397)
0.050 0.008 (1.270 0.203) +0.008 0.004 -0.004 +0.203 0.102 -0.102
0.235 - 0.270 (5.969 - 6.858) 0.560 - 0.650 (14.224 - 16.510)
(
)
1.005 - 1.080 (25.527 - 27.432)
0.105 0.008 (2.667 0.203)
0.050 0.012 (1.270 0.305)
0.150 3.810 MIN 0.015 - 0.025 (0.381 - 0.635) 0.050 (1.270) TYP
DD3 0693
0.027 - 0.037 (0.686 - 0.940) 0.090 - 0.110 (2.286 - 2.794)
0.079 - 0.115 (2.007 - 2.921)
T3 0693
P Package 3-Lead TO-3P Plastic
0.187 - 0.207 (4.75 - 5.26) MOUNTING HOLE 18 - 22 0.115 - 0.145 (2.92 - 3.68) DIA 0.830 - 0.870 (21.08 - 22.10) 0.580 - 0.6OO (14.73 - 15.24) 0.170 - 0.2OO (4.32 - 5.08) 0.060 - 0.080 (1.52 - 2.03)
EJECTOR PIN MARKS 0.105 - 0.125 (2.67 - 3.18) DIA
3 - 7 0.780 - 0.800 0.170 (19.81 - 20.32) (4.32) MAX
0.042 - 0.052 (1.07 - 1.32)
0.215 (5.46) BSC
0.087 - 0.102 (2.21 - 2.59) 0.020 - 0.040 (0.51 - 1.02)
0.074 - 0.084 (1.88 - 2.13)
0.113 - 0.123 (2.87 - 3.12)
P3 0892
LT/GP 06/94 5K REV B * PRINTED IN USA
(c) LINEAR TECHNOLOGY CORPORATION 1994

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