78xx Voltage Regulators
The voltage source in a circuit may have fluctuations and would not give the fixed voltage output. The 78xx (sometimes L78xx, LM78xx, MC78xx...) is a family of fixed linear voltage regulator integrated circuits..The voltage regulator IC maintains the output voltage at a constant value. The xx in 78xx indicates the fixed output voltage it is designed to provide. Eg : 7805 provides +5V regulated power supply. Capacitors of suitable values can be connected at input and output pins depending upon the respective voltage levels.
Individual devices in the series
There are common configurations for 78xx ICs, including 7805 (5 volt), 7806 (6 volt), 7808 (8 volt), 7809 (9 volt), 7810 (10 volt), 7812 (12 volt), 7815 (15 volt), 7818 (18 volt), and 7824 (24 volt) versions. The 7805 is common, as its regulated 5 volt supply provides a convenient power source for most components. Each device in this series has minimum input voltage to be maintained to get regulated output.
| Part Number | Output Voltage (V) | Minimum Input Voltage (V) |
|---|---|---|
| 7805 | +5 | 7.3 |
| 7806 | +6 | 8.3 |
| 7808 | +8 | 10.5 |
| 7810 | +10 | 12.5 |
| 7812 | +12 | 14.6 |
| 7815 | +15 | 17.7 |
| 7818 | +18 | 21.0 |
| 7824 | +24 | 27.1 |
Hence if you have a regulated DC supply and if you want to convert it into a particular voltage then you may use 78xx series voltage regulators.
