©2001 Fairchild Semiconductor Corporation
www.fairchildsemi.com
Rev. 1.0.2
Features
• 3A / 5V Output low dropout voltage regulator
• TO220 Full-Mold package (4PIN)
• Ov ercurrent prote ction , Ther ma l sh utdown
• Overvol tage protecti on, Short- Circuit protection
• With output disable function
Description
The KA378R05 is a low-dropout voltage regulator suitable
for various electronic equipments. It provides constant
voltage power source with TO-220 4 lead full mold package.
Dropout voltage of KA378R05 is below 0.5V in full rated
current(3A). This regulator has various function such as
peak c urre nt protection, th ermal shut down, overvoltage
prote cti on and outpu t disable functi on.
TO-220F-4L
1.Vin 2. Vo 3. GND 4. Vd is
1
Internal Block Diagram
THERMAL SHUTDOWN
BANDGAP REFERENCE
OVERVOLTAGE
PROTECTION
SOA PROTECTION
SHORTCIRCUIT
PROTECTION
1
4
3
2
Vin
Vdis
Vo
GND
HIGH / LOW OUTPUT
ON / OFF
Q1
R1
R2
-
+
-
+
1.4V SHORT-CIRCUIT
KA378R05
Low Dr opout Voltage Regu lator
KA378R05
2
Absolute Maximum Ratings
Electrical Characteristics
(Vin=7V, Io=1.5A, Ta=25°C, unless otherwise specified)
Note:
1.These parameters, although guaranteed, are not 100% tested in production.
2. Junction -to-case thermal resistance test enviroments.
-.Pneuma tic he at sink fixture.
-.Clamping pressure 60psi through 12mm diameter cylinder.
-.Thermal grease applied between PKG and heat sink fixture.
Parameter Symbol Value Unit Remark
Input Voltage Vin 35 V -
Disable Voltage Vdis 35 V -
Output Current Io 3.0 A -
Power Dissipation 1 Pd1 1.5 W No Heatsink
Power Dissipation 2 Pd2 15 W With Heatsink
Junction Temperature Tj 150 °C-
Operating Temperature Topr -20 ~ 80 °C-
Thermal Resistance, Junction-to-Case(Note2) Rθjc 2.9 °C/W -
Thermal Shutdown Temperature Ttsd 150 °C-
Storage Temperature Tstg -65 ~ 150 °C-
Parameter Symbol Conditions Min. Typ. Max. Unit
Output Voltage Vo - 4.88 5 5.12 V
Load Regulation Rload 5mA < Io < 3A - 0.1 2.0 %
Line Regulation Rline 6V < Vin < 12V - 0.5 2.5 %
Ripple Rejection Ratio RR note1 45 55 - dB
Dropout Voltage Vdrop Io = 3A - - 0.5 V
Disable Voltage High VdisH Output Active 2.0 - - V
Disable Voltage Low VdisL Output Disabled - - 0.8 V
Disable Bias Current High IdisH Vdis = 2.7V - - 20 µA
Disable Bias Current Low IdisL Vdis = 0.4V - - -0.4 mA
Quiescent Current Iq Io = 0A - - 10 mA
KA378R05
3
Typical Perfomance Characteristics
Figure 1. Output Voltage vs. Input Voltage
Figure 3. Output Voltage vs. Disable Voltage
Figure 5. Quiescent Current vs. Temperature(Tj)
Figure 2. Quiescent Current vs. Input Voltage
Figu re 4. Output Volta ge vs. Tem pe rature(T j )
Figure 6. Dropout Vol tage vs. Ju nctio n Temperature
51015
Input voltage Vin (V)
6
5
4
3
2
1
7
00
Output voltage Vo(V)
RL=
RL=1.7Ω
8
7
6
5
4
3
00
Output voltage Vo(V)
3
Disable voltage Vdis (V)
0.5 1.5
2
1
122.5
10
8
6
4
2
0
Quescent current Iq(mA)
Junction temperature Tj (oC)
75 125
02550 100
-25
i
80
60
40
20
0
Quescent current Iq(m A)
Input voltage Vin (V)
RL=
0 2 4 6 8 1 0
8
i
5.04
5.02
5.00
5.06
-25
Output voltage Vo(V)
TEMPERATURE Tj(oC)
75 125
02550 100
4.96
4.94
4.92
4.98
125
0.6
0.5
0.4
0.3
0
Dropout voltage Vdrop(V)
Junction temperature Tj( oC)
0.2
0.1
75
02550 100
-25
Io=3A
2.0A
1.0A
0.5A
KA378R05
4
Typical Perfomance Characteristics (Continued)
Figure 7. Power D issipatio n vs. Te mperat ure(T a) Figure 8. Over current Prote ction Characteristics
(Typical Value)
-25
Power dissipation P D(W)
TEMPERATURE Tj(oC)
75 125
02550 100
15
10
5
20
0
D
aOutput Current(A)
Relative output voltage(%)
3.0 5.0
01.02.0 4.0
80
60
20
100
0
40
6.0 7.0
Output Current(A)
Relative output voltage(%)
3.0 5.0
01.02.0 4.0
80
60
20
100
0
40
6.0 7.0
Relative output voltage(%)
3.0 5.0
01.02.0 4.0
80
60
20
100
0
40
6.0 7.0
KA378R05
5
Typical Application
Figu re 1. Ap pli cation Circ uit
• Ci is required if regulator is located an appreciab le distance from power supply filter.
• Co improves stability and transient response.(Co > 47µF)
+
+
12
3
4
Vin
Vdis
Vo
GND
Disable Signal
KA378R05
6
Mechanical Dimensions
Package Dimensions in millimeters
10.00 ±0.20 4.50 ±0.20
2.80 ±0.20
1.50 ±0.20
0.60 ±0.10
3-1.05MIN
3-1.30MAX
(5.00)
(1.00)
(45°)
(1.00)
(1.19) (7.62)
1.25MIN
1.50MAX
(1.19)
ø3.20 ±0.20
3.40 ±0.10
15.60 ±0.20
6.50 ±0.20
15.70 ±0.20
(13.60)
(3.30)
10.30 ±0.30
2.54TYP
[2.54 ±0.25]0.50 +0.10
–0.05
TO-220F-4L
KA378R05
7
Ordering Information
Product Number Package Operating Temperature
KA378R05 TO-220F-4L -20°C to + 80°C
KA378R05
11/13/01 0.0m 001
Stock#DSxxxxxxxx
2001 Fairchild Semicond uctor Corporation
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