MC79xxCT Series
New Product
Vishay
formerly General Semiconductor
3-Terminal Fixed Negative Voltage Regulators
Pin Arrangement
Description
These voltage regulators are intended as complements
to the popular MC78xx Series devices. These negative reg-
ulators are available in the same seven-voltage options as
the MC78xx devices. In addition, one extra voltage
option commonly employed in MECL systems is also
available in the negative MC79xx Series.
Available in fixed output voltage options from –5.0 to –24
volts, these regulators employ current limiting, thermal shut-
down, and safe-area compensation – making them remark-
ably rugged under most operating conditions. With adequate
heatsinking they can deliver output currents in excess of
1.5 ampere.
TO-220
1.
Ground
3
2.
Input
2
1
3.
Output
(heatsink connected to pin 2)
Standard Application
Features
Input
MC79xx
Output
Co
0.1µF
• Output current in excess of 1.5 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
Cin
0.33µF
Notes:
A common ground is required between the input and the output voltages.
The input voltage must remain typically 2.0V more negative even during
the high 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 improves stability and transient response.
Mechanical Data
Case:
TO-220 Package
Weight:
approx. 2.24g
Case outline is on the back page
Internal Block Diagram
GND
R1
R2
Reference
Voltage
+
--
Q1
Q2
Short Circuit
Protection
Output
I1
I2
R
SC
Input
Document Number 74814
11-Jun-02
www.vishay.com
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