TDP-643R PLUS BAR CODE PRINTER
SERVICE MANUAL
- 19 -
3.9 24V/5V Converter Circuit
Fig. 3.9 24V/5V Converter Circuit
Figure 3.10 is the DC-TO-DC (DC24V to DC 5V) converter circuit, which is a
boost system circuit structure. U24 is the DC-TO-DC converter IC, which can
convert voltage by using PWM control mode.
3.10 Stepping Motor Driver /Protection Circuit
Fig. 3.10 Stepping Motor Driver/ Protection Circuit
This is the Stepping Motor and / Protection Circuit. Connector JP12 sends the
pattern as shown in table1. The status of I0 & I1 determines the stepping motor
power level, the power level pattern is shown in table2. Motor port is the
protection pin. When it is at „LOW‟ level, the power of the motor system will be
closed. Power wi
ll be ON again until MOTOR pin is the pulse of „HIGH‟ level.
PHASE1 and PHASE2 determine the pattern of stepping motor drive circuit. For
example, the sequence of PHASE1/PHASE2 in full step mode is 0/0
→
0/1
→
1/1
→
1/0.
