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MC79XX/MC79XXA/LM79XX
3-Terminal 1A Negative Voltage Regulator
Features
Description
• Output Current in Excess of 1A
• Output Voltages of -5, -6, -8 , -9, -10, -12, -15, -18 and 24V
• Internal Thermal Overload Protection
• Short Circuit Protection
• Output Transistor Safe Operating Area Compensation
The MC79XX / MC79XXA/ LM79XX series of three
terminal negative regulators are available in TO-220
package and with several fixed output voltages, making
them useful in a wide range of applications. Each type
employs internal current limiting, thermal shut down and
safe operating area protection, making it essentially
indestructible.
TO-220
Vin
1
1. GND 2. Input 3. Output
Internal Block Digram
GND
R1
VOLTAGE
REFERENCE
R2
Output
Out
+
Q1
Q2
I1
I2
PROTECTION
CIRCUITRY
Rsc
In
Input
Rev. 1.0.1
©2002 Fairchild Semiconductor Corporation
MC79XX/MC79XXA/LM79XX
Electrical Characteristics (MC7906) (Continued)
(VI = -11V, IO = 500mA, 0°C ≤TJ ≤ +125°C, CI =2.2µF, CO =1µF, unless otherwise specified.)
Parameter
Line Regulation (Note1)
Load Regulation (Note1)
Quiescent Current
Quiescent Current Change
Temperature Coefficient of VD
VO
∆VO
∆VO
IQ
∆IQ
∆Vo/∆T
Min.
Typ.
Max.
TJ = +25°C
Output Voltage
Symbol
Conditions
-5.75
-6
-6.25
IO = 5mA to 1A, PO ≤ 15W
VI = -9V to -21V
-5.7
-6
-6.3
VI = -8V to -25V
-
10
120
VI = -9V to -13V
-
5
60
TJ = +25°C
IO = 5mA to 1.5A
-
10
120
TJ =+25°C
IO = 250mA to 750mA
-
3
60
TJ =+25°C
-
3
6
IO = 5mA to 1A
-
0.05
0.5
VI = -8V to -25V
-
0.1
1.3
IO = 5mA
-
-0.5
-
mV/°C
-
130
-
µV
TJ = +25°C
Unit
V
mV
mV
mA
mA
Output Noise Voltage
VN
f = 10Hz to 100kHz
TA =+25°C
Ripple Rejection
RR
f = 120Hz
∆VI = 10V
54
60
-
dB
Dropout Voltage
VD
TJ = +25°C
IO = 1A
-
2
-
V
Short Circuit Current
ISC
TJ = +25°C, VI = -35V
-
300
-
mA
Peak Current
IPK
TJ = +25°C
-
2.2
-
A
Note
1. Load and line regulation are specified at constant junction temperature. Changes in VO due to heating effects must be taken
into account separately. Pulse testing with low duty is used.
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