MC78XX Datasheet, PDF (22/28 Pages) Fairchild Semiconductor – 3-Terminal 1A Positive Voltage Regulator

MC78XX/LM78XX/MC78XXA
Input
CI
MC78XX/LM78XX
Co
Output
Figure 9. Constant Current Regulator
Notes:
(1) To specify an output voltage. substitute voltage value for "XX." A common ground is required between the input and the
Output voltage. The input voltage must remain typically 2.0V above the output voltage even during the low point on the input
ripple voltage.
(2) CI is required if regulator is located an appreciable distance from power Supply filter.
(3) CO improves stability and transient response.
Input
CI
MC78XX/LM78XX
Co
Output
I_RI ≥ 5IQ
VO = VXX(1+R2/R1)+IQR2
Figure 10. Circuit for Increasing Output Voltage
Input
CI
MC7805
LM7805
LM741
Output
Co
IRI ≥5 IQ
VO = VXX(1+R2/R1)+IQR2
Figure 11. Adjustable Output Regulator (7 to 30V)
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