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Motor driver ICs BA6285FS / BA6285FP
Circuit operation
(1) Input section
The four output modes are controlled by two logic inputs.
Current flows from OUT1 to OUT2 when F
IN is HIGH and
R
IN is LOW, and from OUT2 to OUT1 when RIN is HIGH
and F
IN is LOW (refer to the truth table). The input circuit
can be operated by a logic circuit with a current capacity
of 120 170µA.
(2) Output section
Current flows from OUT1 to OUT2 during forward rota-
tion, and from OUT2 to OUT1 during reverse rotation.
The output voltages V
OH and VOL are given by :
V
OH [V]=VREF – VCE (sat) (PNP) – VBE (NPN)
V
OL [V]=VCE (sat) (NPN)
V
CE and VBE are functions of the output current (see elec-
trical characteristic curves). The output current can be
set with the V
REF pin.
(3) Power saving circuit
All circuits are turned OFF when the F
IN and RIN input pins
are both LOW or the POWER SAVE pin is HIGH. This cir-
cuit saves power during standby mode by leaving the
outputs OPEN.
