Am zis sa nu mai scriu la partea tehnica dar schema de mai sus nu are legatura cu inlocuirea tranz. intern de limitare cu unul extern. Pinul 10 (pt ca 9 este la masa) va fi la 6,2V. Pinul 13 va fi cu 2x Ube mai sus. Acolo este si colectorul tranz. de limitare. Rezistenta de limitare va fi in emitor 3055, deci la potentialul iesirii. Tranzistorul de limitare va avea in baza 30V (sau 40 sau 70V) iar in colector cam 7,5V. O functionare exemplara!!
Proven. No wonder after 50 years, it is known what you may expect and what not.
Stable. Relying on a buried Zener low noise reference, it can compete with a lot of newer chips when it comes to stability (it does have a long term stability rating in the datasheet, few new chips have that). Tempco is also very good, also when compared to newer chips.
Low Noise. One of the best low noise regulators even today (when hooked up properly). Reason one is the low noise buried Zener reference, reason two is the fact that the reference voltage can be noise filtered before going into the error amp. Jörn Bartels DK7JB did a very good comparative study of different voltage regulators. It can be found here.
Wide voltage range. Input voltage goes up tp 40V constant, with 50V pulses allowed. There is even an (obsolete) 80V version, the L146CB.
Support for external pass transistors, keeping on-chip dissipation (and therefore drift) low.
Compensation by the user. You can tailor the frequency response to your application (but you also have to do that because there is no internal compensation).
Very flexible. Can serve as positive, negative, shunt, pass, floating or switching regulator or as a temperature controller.
Extended Temperature Range available. You can get CDIP14 chips with an operating temperature range from -55°C to +125°C.
Cheap. A few 10 €Cent, and its yours.