Electronic Circuit Descriptions; Principle Of Operation; Power Supply Block - Panasonic KX-P1180 Service Manual

KX-P1180
8. Electronic Circuit Descriptions
8.1 Principle of Operation
The KX-P1180 has three switches and two sensors. The home position switch sets a reference for the
carriage and is necessary for aligning the first print position. The Friction/Tractor switch detects the way
of paper-feed by Friction or Tractor. The Bail Lever Switch is actuated for paper auto loading and memoload.
The paper out sensors detect paper end, and prevent printing operation when the printer is out of paper.
The printer has three drive circuits; carriage spacing motor, paper feed motor and printhead.
The control panel is composed of switches and LEDs which indicate the various states of the printer.
Logic Diagram
Drive
Circult
Operation Switch
Indicator
Sensor
Micro Switch
Power Supply
Circuit
8.2 Circuitry
8.2.1 Power Supply Block
(1) Power and Filter Block
The fuse and filters are attached to a single printed circuit board. Primary power enters the power switch -
and passes through fuse F501(1.6A). Absorption capacitors (C501, C502 and C503) together with
choke(L501), located near the primary transformer, prevent noise from entering the circuit from the power
source, and prevent noise from leaving the printer to the power source. As a result, the printer's digital
circuitry operates very stably, unaffected by line noise, and prevents printer noise from affecting the outside
power source.
FSOl SHSO!
AC27V
Rated Voltage Input
AC10V
+ (at no current load)