STC78L00 Suntac Electronic, STC78L00 Datasheet - Page 7

• Manufacturer Part Number: STC78L00
• Description: 100 mA Positive Oltage Regulators
• Manufacturer: Suntac Electronic

Design Considerations
designed with Thermal Overload Protection that shuts
down the circuit when subjected to an excessive power
overload condition. Internal Short Circuit Protection limits
the maximum current the circuit will pass.
capacitors are not required. However, it is recommended
that the regulator input be bypassed with a capacitor if the
regulator is connected to the power supply filter with long
wire lengths, or if the output load capacitance is large. The
The STC78L00 Series of fixed voltage regulators are
In many low current applications, compensation
Input
0.33mF
STC78L05
The
when connected as above. In order to minimize dissipation the
MC78L05C
the current as follows:
For example, a 100 mA current source would require R to be a
50 W, 1/2 W resistor and the output voltage compliance would be
the input voltage less 7 V.
I
STC78L00
IB
MC78L00
= 3.8 mA over line and load changes
Figure 8. Current Regulator
is chosen in this application. Resistor R determines
regulators can also be used as a current source
STC78L05
MC78L05A
I
O
=
5.0 V
R
+ I
B
I
O
R
Grounded Load
APPLICATIONS INFORMATION
Current to
Constant
STC78L00 Series
8
input bypass capacitor should be selected to provide good
high−frequency characteristics to insure stable operation
under all load conditions. A 0.33 mF or larger tantalum,
mylar, or other capacitor having low internal impedance at
high frequencies should be chosen. The bypass capacitor
should be mounted with the shortest possible leads directly
across the regulators input terminals. Good construction
techniques should be used to minimize ground loops and
lead resistance drops since the regulator has no external
sense lead. Bypassing the output is also recommended.
+20V
0.33mF
Figure 9. ± 15 V Tracking Voltage Regulator
0.33mF
Figure 10. Positive and Negative Regulator
20V
+V
−V
0.33mF
0.33mF
I
I
MC78L15A
STC78L15
MPS U55
STC78LXX
STC79LXX
MC78LXXA
MC79LXXA
6
6.5
MC1741
4
7
−
+
MPS A70
2
3
0.1mF
0.1mF
+V
−V
10k
10k
O
O
+V
−V
O
O