View lm7905 datasheet:

www.fairchildsemi.com MC79XX/MC79XXA/LM79XX 3-Terminal 1A Negative Voltage Regulator Features Description • Output Current in Excess of 1A The MC79XX / MC79XXA/ LM79XX series of three • Output Voltages of -5, -6, -8 , -9, -10, -12, -15, -18 and - terminal negative regulators are available in TO-220 24V package and with several fixed output voltages, making • Internal Thermal Overload Protection them useful in a wide range of applications. Each type • Short Circuit Protection employs internal current limiting, thermal shut down and • Output Transistor Safe Operating Area Compensation safe operating area protection, making it essentially indestructible. TO-220 Vin 1 1. GND 2. Input 3. Output Internal Block Digram GND R1 VOLTAGE R2 REFERENCE Output Out + Q1 - Q2 P