Outline Of Control Electronics; Configuration - Brother P-touch PT-2730 Service Manual

2.2 Outline of Control Electronics

2.2.1

Configuration

Fig. 2.2-1 shows a block diagram of the control electronics of this machine. The control
electronics consists of four printed circuit boards (main PCB, power supply PCB, key
PCB, and cassette sensor PCB), two DC motors (tape feed motor and cutter motor),
thermal print head ASSY, backlight module, sensors and encode.
Note: When soldering chips on PCBs, use lead-free solder.
■ Main PCB, Key PCB
These manages all the components including an LCD, key pad, two DC motors, and
thermal print head.
■ Power Supply PCB
This has the electrolytic capacitors (filters for output lines), AC adapter jack, USB port,
battery terminal plates, and other related electronic devices to supply the control
electronics and DC motors with power from the dry cells or AC adapter.
■ DC Motors
This machine has two DC motors - tape feed motor and cutter motor. The former feeds
tape and ink ribbon and the latter drives the cutter to cut tape.
■ Thermal Print Head
This is a thick-film thermal print head which integrates a heat generator (consisting of
128 heating elements vertically aligned) and driver circuitry.
■ Cassette Sensor PCB
This cassette sensor PCB has seven switches. The six switches detect the tape
cassette currently loaded. The other one switch detects the opening/closing of the
cassette cover.
■ Encode
The encode, which consists of an encode disc gear and a pair of photo interrupters,
detects the rotation angle/direction of the tape feed motor.
■ Backlight module (COG type LCD module)
This lights up the backlight for the LCD.
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