ROHM BA6467FP-Y

Motor driver ICs
3-phase motor driver for VCR cylinders
BA6467FP-Y
The BA6467FP-Y is a motor driver developed for cylinders. It contains a power supply with a constant voltage 8V, and
a start / stop pin that opens the output.
Applications
VCR cylinders
Features
1) 3-phase, full-wave, pseudo-linear drive system.
2) Internal constant voltage power supply (8V).
3) Internal thermal shutdown circuit.
Absolute maximum ratings (Ta = 25C)
Recommended operating conditions (Ta = 25C)
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Motor driver ICs
BA6467FP-Y
Block diagram
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Motor driver ICs
Pin descriptions
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BA6467FP-Y
Motor driver ICs
Input / output circuits
(1) Start / stop (ST / SP: pin 9)
(3)
Torque control input (EC: pin19, ECR: pin 18)
(4)
Coil output (A1: pin 6, A2: pin4, A3: pin 3)
BA6467FP-Y
(2)
Torque limit (TL: pin20)
(5) Hall input (H1: pin10, H1–: pin 11, H2: pin 12,
H2–: pin 13, H3: pin 14, H3–: pin 15)
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Motor driver ICs
Electrical characteristics (unless otherwise noted, Ta = 25C, VCC = 12V)
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BA6467FP-Y
Motor driver ICs
Circuit operation
(1) Hall I / O
The 3-phase Hall signal is amplified in the hall amplifiers
and sent to the matrix circuit, where the signal is further
amplified and combined. After the signal is converted to
a current in the amplitude control circuit, the current is
supplied to the output driver, which then provides a motor
drive current. The phases of the Hall input signal, output
voltage, and output current are shown in Fig.1.
BA6467FP-Y
(2) Torque control pin
The output current can be controlled by adjusting the
voltage applied to the torque control pin.
(3) Start / stop pin
The motor is in the run mode when the pin input voltage
is 3.5V or more and in the standby mode (all output transistors are off) when the voltage is 1.2V or less.
(4) Power ground pin (RNF pin)
The power ground pin is the output stage ground pin.
Connect a resistor (0.5Ω recommended) between this
pin and the ground to monitor the output current.
(5) Phase compensation pin (CNF pin)
Connect a capacitor between this pin and VCC if the output tends to oscillate.
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Motor driver ICs
Application example
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BA6467FP-Y
Motor driver ICs
Operation notes
(1) Start / stop pin
The I / O equivalent circuit of the start / stop pin is shown
in Fig.4. The pin has a temperature dependence of
*7mV / C, and its resistance can vary ±30%. The voltage on this pin should be less than VREG.
BA6467FP-Y
(3) Torque limit pin
The output current can be limited by applying a voltage
to the torque limit pin. Control is provided so that this pin
will have the same potential as the power ground pin
(RNF).
Note that there is a voltage offset on this pin. The RNFpin voltage is 0.325V when the TL-pin voltage is 0.4V
(typical) and the RNF-pin resistance is 0.5Ω. Note that
the voltage offset changes with RNF-pin resistance.
Connect the TL pin to VREG (pin 23) when the TL pin is not
used.
(2) Hall input
The input circuit of the Hall input pins is shown in Fig.5.
The Hall devices can be connected in either series or parallel. The input Hall signal should be within the range of
the Hall input common-mode voltage.
(4) Thermal shutdown circuit (TSD)
The thermal shutdown circuit puts the coil outputs (A1,
A2, and A3) to the open state at the temperature of
175C (typical). There is an approximate 25C temperature hysteresis.
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Motor driver ICs
Electrical characteristic curves
External dimensions (Units: mm)
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BA6467FP-Y