Datasheet BA6222 Datasheet (ROHM)

Motor driver ICs

Reversible motor driver

BA6222

The BA6222 is a reversible-motor driver with a maximum output current of 2.2A. Two logic inputs allow four output mo­des: forward, reverse, idling, and braking. The motor revolving speed can be set arbitrarily by controlling the voltage
applied to the motor.

Applications
VCRs

Features

1) Large output current. (I

2) Built-in thermal shutdown circuit.

3) Output voltage can be adjusted arbitrarily with the
output voltage setting pin. Because the pin has a gain
of 11.4dB, a high output voltage can be set with a low
input voltage.

Block diagram

OMax. = 2.2A)

4) Small standby circuit current.

Equivalent circuit for pins 5 and 6

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Motor driver ICs BA6222

FInput / output truth table

FAbsolute maximum ratings (Ta = 25_C)

FElectrical characteristics (unless otherwise noted, Ta = 25_C, V

CC = 12V)

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Motor driver ICs BA6222

FApplication example

(4) 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.
(5) Input pins
Voltage should never be applied to the input pins when
the V

CC voltage is not applied to the IC. Similarly, when

V

CC is applied, the voltage on each input pin should be

CC and within the guaranteed range for the

FOperation notes
(1) Output voltage control pin (pin 4)
The voltage at pin 4 is related to the HIGH output voltage
(V

OH) as follows :

OH = 4  V4  Vofs

V
where Vofs is the error voltage, which varies with the out­put current and the chip temperature. The output voltage
is about four times the voltage at pin 4.
The V

4-value can be classified into three ranges accord-

ing to the output state :

OH is at or near 0V

A : V

OH is four times the gain

B : V

OH-value is saturated

C : V
An oscillation may occur if a circuit having an output im­pedance of more than a few hundred ohms is connected
to pin 4. In this case, connect a capacitor of at least
3300pF between pin 4 and GND.
(2) Thermal shutdown circuit
The thermal shutdown circuit turns off the driver output
if the chip temperature rises to about 150_C. The shut­down signal is not latched.
(3) Make sure that pin voltages will not exceed the sup­ply voltage by more than 0.3V or will not become less
than the GND pin voltage by more than 0.3V.

less than V
electrical characteristics.
(6) 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.
(7) 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.
(8) 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.
(9) 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.

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Motor driver ICs BA6222

(10) ASO
Make sure that the output current and supply voltage do
not exceed the ASO values.
(11) Precautions for input mode switching
To ensure reliability, it is recommended that the mode
switching for the motor pass once through the open
mode.
(12) 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.
(13) 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.
C

1 : Power supply filter capacitor . Place as near as pos-

sible to pin 1.

2, C3 : Capacitors to prevent both output transistors

C

being turned on at the same time.

4 : Surge voltage absorbing capacitor

C
C

5 : Oscillation preventing capacitor. An oscillation may

occur if a circuit having an output impedance of
more than a few hundred ohms is connected to pin

4. In this case, connect a capacitor of at least
3300pF.
R : Resistor used for reducing collector loss and lim­iting the short-circuit current. A resistance range of

4.7  10Ω is recommended.

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Motor driver ICs BA6222

Electrical characteristic curves

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Motor driver ICs BA6222

External dimensions (Units: mm)

410