THREE–AMPERE
POSITIVE FIXED
VOLTAGE REGULATORS
ORDERING INFORMATION
DEVICE TYPE/NOMINAL OUTPUT VOLTAGE
MC78T05
MC78T08
5.0 V
8.0 V
MC78T12
MC78T15
12 V
15 V
Order this document by MC78T00/D
T SUFFIX
PLASTIC PACKAGE
CASE 221A
3
1
2
Pin 1. Input
2. Ground
3. Output
Heatsink surface is connected to Pin 2.
MC78TXXCT
MC78TXXACT
MC78TXXBT#
MC78TXXABT#
Package
Device
Operating
Temperature
Range
TJ = 0
°
to
+125
°
C
XX Indicates nominal voltage.
* 2% regulators available in 5, 12 and 15 V devices.
# Automotive temperature range selections are avail-
able with special test conditions and additional
tests. Contact your local Motorola sales office for
information.
VO
Tol.
4%
2%*
4%
2%*
TJ = –40
°
to
+125
°
C
Plastic
Power
Plastic
Power
SEMICONDUCTOR
TECHNICAL DATA
1
MOTOROLA ANALOG IC DEVICE DATA
This family of fixed voltage regulators are monolithic integrated circuits
capable of driving loads in excess of 3.0 A. These three–terminal regulators
employ internal current limiting, thermal shutdown, and safe–area
compensation. Devices are available with improved specifications, including
a 2% output voltage tolerance, on AC–suffix 5.0, 12 and 15 V device types.
Although designed primarily as a fixed voltage regulator, these devices
can be used with external components to obtain adjustable voltages and
currents. This series of devices can be used with a series–pass transistor to
supply up to 15 A at the nominal output voltage.
Output Current in Excess of 3.0 A
Power Dissipation: 25 W
No External Components Required
Output Voltage Offered in 2% and 4% Tolerance*
Thermal Regulation is Specified
Internal Thermal Overload Protection
Internal Short Circuit Current Limiting
Output Transistor Safe–Area Compensation
MAXIMUM RATINGS
(TA = +25
°
C, unless otherwise noted.)
Rating
Symbol
Value
Unit
Input Voltage (5.0 V – 12 V)
Input Voltage
(15 V)
VI
35
40
Vdc
Power Dissipation and Thermal Characteristics
Plastic Package (Note 1)
TA = +25
°
C
Thermal Resistance, Junction–to–Air
TC = +25
°
C
Thermal Resistance, Junction–to–Case
PD
R
θ
JA
PD
R
θ
JC
Tstg
TJ
Internally Limited
65
Internally Limited
2.5
°
C/W
°
C/W
Storage Junction Temperature
+150
°
C
Operating Junction Temperature Range
(MC78T00C, AC)
0 to +125
°
C
NOTES:
1.Although power dissipation is internally limited, specifications apply only
for PO
≤
Pmax, Pmax = 25 W.
Simplified Application
Input
Cin*
0.33
μ
F
Output
CO**
MC78TXX
A common ground is required between the input and the output voltages. The input voltage must
remain typically 2.2 V above the output voltage even during the low point on the input ripple voltage.
XX these two digits of the type number indicate voltage.
*
* Cin is required if regulator is located an appreciable distance from power supply filter.
**
(See Applications Information for details.)
** CO is not needed for stability; however, it does improve transient response.
Motorola, Inc. 1996
Rev 1