Fixed Negative Voltage Regulator:
As we have seen many times previously, positive and negative regulated power supply voltages are often required. In response, many manufacturers have developed negative three-terminal regulators. They offer the same types of features and protection as are found in positive voltage regulators.
The 7900 series of fixed output negative voltage regulators are complements to the 7800 series devices. The fixed negative voltage regulator are available in the same eight voltage options as the 7800 devices. In addition, two extra voltage options -2 V, and -5.2 V are also available in the negative 7900 series, as shown in Table 43.3.