The LM105 series are positive voltage regulators similar to
the LM100, except that an extra gain stage has been added
for improved regulation. A redesign of the biasing circuitry removes
any minimum load current requirement and at the
same time reduces standby current drain, permitting higher
voltage operation. They are direct, plug-in replacements for
the LM100 in both linear and switching regulator circuits with
output voltages greater than 4.5V. Important characteristics
of the circuits are:
• Output voltage adjustable from 4.5V to 40V
• Output currents in excess of 10A possible by adding external
transistors
• Load regulation better than 0.1%, full load with current
limiting
• DC line regulation guaranteed at 0.03%/V
• Ripple rejection on 0.01%V
• 45 mA output current without external pass transistor
(LM305A)
Like the LM100, they also feature fast response to both load
and line transients, freedom from oscillations with varying resistive
and reactive loads and the ability to start reliably on
any load within rating. The circuits are built on a single silicon
chip and are supplied in a TO-99 metal can.
The LM105 is specified for operation for −55°C £ TA £
+125°C, and the LM305/LM305A is specified for 0°C £ TA £
+70°C.
Schematic and Connection Diagrams
DS007755-1
