MC78xxCT Series
3-Terminal Fixed
Positive Voltage Regulators
MC78xxCT
TO-220AB
Pin Definition
1. Input
2. Ground
3. Output
(Heatsink/ tab
connected to pin 2)
1
2
3
Standard Application
Input
Description
Output
MC78xx
Co
0.1µF
Cin
0.33µF
Notes:
A common ground is required between the input and the output voltages.
The input voltage must remain typically 2.0V above the output voltage
even during the low point on the input ripple voltage.
xx = these two digits of the part number indicate output voltage.
Cin is required if regulator is located an appreciable distance from power
supply filter.
Co is not needed for stability, however, it does improve transient response.
Internal Block Diagram
Input
Series
Pass
Element
1
Current
Generator
Starting
Circuit
Reference
Voltage
New
t
duc
Pro
Output
These voltage regulators are monolithic integrated
circuits designed as fixed-voltage regulators for a
wide variety of applications including local, on-card
regulation. These regulators employ internal current
limiting, thermal shutdown, and safe-area compensation. With adequate heatsinking the MC78xxCT
can deliver output currents in excess of 1.5 ampere.
Although designed primarily as a fixed voltage
regulator, these devices can be used with external
components to obtain adjustable voltages with
currents.
Features
•
•
•
•
•
•
Output current in excess of 1.0 ampere
No external components required
Internal thermal overload protection
Internal short-circuit current limiting
Output transistor safe-area compensation
Output voltage offered in 2% tolerance
3
Mechanical Data
SOA
Protection
Case: TO-220 Package
Error
Amplifier
Case outline is on the back page.
Thermal
Protection
GND
2
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