Lambda LL Series Instruction Manual page 7

MOUNTING
laboratory bench, table top. . Lies flat or stands erect.
MODEL OPTIONS
r Standard LL power supplies can be obtained
for 205-265 VAC, 47-57 Hz input, derate cur-
rent rating by 10%.
OVERVOLTAGE PROTECTOR ACCESSORY . . . Externally mounted, Overvoltage Protectors
LC-OV-10, LC-OV-11 and LC-OV-12 are available
for use with models LL-901, LL-901-0V, LL-
902, LL-902-OV, LL-903 and LL-903-0V,
THEORY OF OPERATION
GENERAL
The Lambda power supply consists of an AC input circuit and transformer; a bias
supply consisting of an auxiliary rectifier and filter, and pre-regulator*; a main
regulator circuit consisting of the main rectifier and filter, a series regulator,
emitter follower driver, a current comparator*, a voltage comparator*, an amplifier*,
current and voltage sensing networks and a voltage reference circuit*.
= This circuit element is part of integrated circuit (1С1) in
the supply.
The circuit arrangement is shown in block diagram form, Figure 2. The circuit-
ry is discussed with reference to the block diagram and the schematic diagram.
FUNCTIONAL DESCRIPTION
Single phase input power is applied to transformer Tl through the input circuit
which contains a fuse (F2) to protect the power supply against internal faults.
The main rectifier, a full wave rectifier, provides the power which is filtered
by capacitor C6 and then regulated via a series regulator and delivered to the out-
put. Half-wave auxiliary rectifier CRI provides voltage filtered by capacitor Cl
for the preregulator located in ICl. The reference element, powered by the prereg-
ulator, provides a reference voltage for the current comparator and the voltage
comparator.
IM-LL | 3