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The blocks are as
1. Phase Drivers
follows.
(A to D)
These drivers are turned on and off upon receiving the drive pulses AO 1 to DO 1 from the MCU (4 B).
When the input signal is HIGH, the corresponding phase driver turns on.
2.
and
or
compares the reference voltage at the minus terminal with the voltage applied to the
plus terminal, which is from the current detection resistor
or
When the reference voltage
is lower than the voltage across the current detection resistor, the output goes HIGH, and the voltage
applied to
or
is shut off.
3. CR Motor Power Switches (A/C phase and B/D phase)
This switch is turned on and off upon receiving the output from
1
When the output from
is LOW, +35 V is applied
to
4.
The
generates a square wave which is used as the reference for chopper type driving (Pulse Width
Modulation control).
5. Current Detection Resistors
and
Voltage is induced across the current detection resistor in proportion to the
CR motor coil. This voltage is input to the plus terminal
of
current that flows to the
6. Reference Voltage Generation Circuit
The current applied to the CR motor coil is determined by the reference voltage applied to the minus
terminal of
(Refer to the section
on Reference Voltage Generation Circuit.)
7. Surge Voltage Absorbing Circuit I
When the phase A driver or phase C driver (phase B driver or phase D driver) turns off, positive surge
voltage is induced at the CR motor coil. This voltage is absorbed by
via fly wheel diode DA 1 or
or
8. Surge Voltage Absorbing Circuit II
When the phase A driver or phase C driver (phase B driver or phase D driver) turns on, negative surge
voltage is induced at the CR motor coil. This voltage is absorbed by
via flywheel diode DAC 1
1).
2-88
Summary of Contents for LQ-2550
Page 1: ...L Q 2 5 5 0 TECHNICAL MANUAL EPSON ...
Page 240: ...REV A P r cl Figure 6 3 LQ 2550 Lubrication and Adhesive Application Points Diagram 2 6 3 ...
Page 241: ...REV A 7 i_ Figure 6 4 LQ 2550 Lubrication and Adhesive Application Points Diagram 3 6 4 ...
Page 252: ...REV A I 1 I 7 v m o m x b Figure A 6 PPD781OHG Block Diagram A 7 ...
Page 297: ...REV A 1 L I Irl N I i t 1 I I x Figure A 50 ROPSE Board Circuit Diagram A 52 ...