Rohm BA6259 2-channel reversible motor driver Datasheet

Motor driver ICs
2-channel reversible motor driver
BA6259N
The BA6259N incorporates two reversible-motor drivers.
Features
1) Two reversible-motor driver circuits are built in.
2) Built-in thermal shutdown circuit.
Block diagram
Absolute maximum ratings (Ta = 25C)
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3) SIP10pin package.
Motor driver ICs
BA6259N
Electrical characteristics (unless otherwise noted, Ta = 25C and VCC = 12V)
Input / output truth table
Application example
C2, C3 : Capacitors for preventing parasitic oscillation.
Though the optimum capacitance depends on such PCB
arrangement factors as the power supply circuit, motor
characteristics, and conductor foil patterns, a range of
0.011µF is recommended.
C4, C5 : Capacitors for preventing parasitic oscillation.
They may or may not be required, depending on the PCB
arrangement. A capacitance range of 0.0110µF is recommended.
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Motor driver ICs
BA6259N
Control pin equivalent circuit
Oparation notes
(1) Use the BA6259N with VR (pin 8) short-circuited to
VCC2 (pin 9). The VCC2 potential should be lower than the
VCC1 potential. Under these conditions, the IC provides a
HIGH level output voltage of 11.3V (typical, VCC2=12V).
Because a single transistor is used for the low-side output stage, the LOW level output voltage is further lowered. This results in a wide range of motor drive voltage.
(2) Though the IC input pins can be directly connected
with MOS output pins, it is recommendable to connect resistors of a few kiloohms to do3en of kiloohms between
the pins for the sake of pin protection.
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(3) Due to the effects of capacitors C2C5, the motor
that is not being driven could be momentarily driven during mode switching. Check for this problem when designing your application.
(4) It is recommendable to arrange your design so that
voltage rises at VCC1 prior to VCC2 when turning on the
power, and voltage falls at VCC1 after VCC2 when turning
off the power.
(5) Thermal shutdown circuit
When the thermal shutdown circuit is activated, the output is left OPEN. The circuit is activated when the IC junction temperature rises above 170C. The temperature
difference between the activation and deactivation settings is about 30C.
(6) The quality of these products have been carefully
checked; however, use of the products with applied voltages, operating temperatures, or other parameters that
exceed the absolute maximum rating given may result in
the damage of the IC and the product it is used in. If the
IC is damaged, the short mode and open modes cannot
be specified, so if the IC is to be used in applications
where parameters may exceed the absolute maximum
ratings, then be sure to incorporate fuses, or other physical safety measures.
(7) Input pins
Voltage should never be applied to the input pins when
the VCC voltage is not applied to the IC. Similarly, when
VCC is applied, the voltage on each input pin should be
less than VCC and within the guaranteed range for the
electrical characteristics.
(8) Back-rush voltage
Depending on the ambient conditions, environment, or
motor characteristics, the back-rush voltage may fluctuate. Be sure to confirm that the back-rush voltage will not
adversely affect the operation of the IC.
Motor driver ICs
BA6259N
(9) Large current line
Large currents are carried by the motor power supply and
motor ground for these ICs.
Therefore, the layout of the pattern of the PC board and
the constants of certain parameters for external components, such as the capacitor between the power supply
and ground, may cause this large output current to flow
back to the input pins, resulting in output oscillation or
other malfunctions. To prevent this, make sure that the
PC board layout and external circuit constants cause no
problems with the characteristics of these ICs.
(10) Power dissipation
The power dissipation will fluctuate depending on the
mounting conditions of the IC and the ambient environment. Make sure to carefully check the thermal design of
the application where these ICs will be used.
(11) Power consumption
The power consumption by the IC varies widely with the
power supply voltage and the output current. Give full
consideration to the power dissipation rating and the
thermal resistance data and transient thermal resistance
data, to provide a thermal design so that none of the ratings for the IC are exceeded.
(12) ASO
Make sure that the output current and supply voltage do
not exceed the ASO values.
(13) Precautions for input mode switching
To ensure reliability, it is recommended that the mode
switching for the motor pass once through the open
mode.
(14) In-rush current
There are no circuits built into these ICs that prevent inrush currents. Therefore, it is recommended to place a
current limiting resistor or other physical countermeasure.
(15) Factors regarding the thermal, power supply, and
motor conditions
If the potential of the output pin sways greatly and goes
below the potential of ground, the operation of the IC may
malfunction or be adversely affected. In such a case,
place a diode between the output and ground, or other
measure, to prevent this.
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Motor driver ICs
Electrical characteristic curves
External dimensions (Units: mm)
508
BA6259N
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