The LM7805 is an integrated positive voltage regulator which takes DC current and regulates it down to a nice, stable 5 volts. Features include builtin thermal and short circuit protection to keep the magic smoke sealed safely within. The maximum peak output current is 2.2 amps, and the maximum constant load is 1 amp. The maximum input voltage is 35 volts, making it capable of providing a 5vdc output off of an extremely wide range of input voltages. Note that the input voltage must be 7 volts or greater to produce stable output.
The LM7805 is packaged in a TO-220 case or a D-Pak SMD package. The pinout for either is as follows:
TO-220 D-PAK
----- tab ----- tab
| O | |-----|
|-----| | |
| | |_____|
|_____| | | |
| | | 1 2 3
1 2 3 1=Input, 2 and tab=Ground, 3=Output
The only support component needed along with an LM7805 regulator is a small
capacitor (.1
microfarad or so, value not critical) between the output and ground, to prevent self-oscillation of the output transistor circuit.
Similar parts with different output
voltages:
Number Output Voltage
LM7806 +6.0
LM7808 +8.0
LM7809 +9.0
LM7810 +10.0
LM7812 +12.0
LM7815 +15.0
LM7818 +18.0
LM7824 +24.0