I'm looking at the schematic for the MC1460 voltage regulator. At the top it has three current mirrors, each with an NPN-PNP pair. Is there a name for that transistor structure? These pairs look like Sziklai pairs except there is an emitter-base connection rather than an emitter-collector connection, and four connections in total.
I've experimented with the circuit in LTspice, but I'm not sure why they implemented it this way. It's more complex than other current mirrors I've looked at. The mirrored currents are sourced by the PNP collectors, but I'm not sure what current is controlling the mirror. There's a Zener-controlled current going to the bases of the NPN transistor, and a second current going through resistors to the emitter-collector connection. It appears that both of these currents affect the output. Any suggestions on how this current mirror works?