The BA6209 and BA6209N are reversible motor drivers for brushed motors. Two logic inputs allow three output modes: forward, reverse and brake. By controlling the applied voltage, the motor speed can be arbitrarily set to the motor with the control pin voltage VR.

application

VCRs and cassette tape recorders

Features

1) Power transistors can handle large currents (max 1.6A).

2) Apply the brake when stopping the motor.

3) Built-in function to absorb the resulting impact current for reversing and braking.

4) Motor speed control pin.

5) The standby current is small. (VCC = 12V , IO = 5.5mA)

6) Stable operation during mode change is reversed forward and vice versa.

7) Interface with CMOS devices.

block diagram

Measurement circuit diagram

circuit operation

Forward/reverse control, forced stop and combined control of inrush currents FIN and FIN absorb the RIN input state.

(1) Forward/reverse control circuit

When FIN is high and RIN is low, current flows from OUT1 to OUT2. When FIN is low and RIN is high, current flows from OUT2 to OUT1.

(2) Forced stop circuit

Power off the motor and apply the brake by setting both RIN and FIN to HIGH or both to LOW

By absorbing the back EMF of the motor.

(3) Inrush current absorption circuit

When a high voltage is generated on OUT1 and OUT2 (caused by motor reversal), the internal comparator detects the high voltage and turns on the internal circuit that absorbs the inrush current.

(4) Drive circuit

The forward direction of the motor is connected together OUT1 and OUT2 corresponds to the current from OUT1 to OUT2, the reverse direction corresponds to

Current flows from OUT2 to OUT1. The output voltage (VOUT) applied to the motor is given by: VOUT(V) = VZD VCE(sat.) = VZD 0.2 (IOUT = 100mA) where VZD is the constant voltage Zener voltage diode (ZD) connected to lead feet 4. If Vref remains OPEN, the output voltage (VOUT) is given by

Equation:

VOUT(V)=VCC1 VCE(sat.)(PNP) 2VF VCE(sat.)=VCC1 1.8(IOUT=100mA)

Instructions

(1) Resistor divider IC power consumption In order to reduce the power consumption in the IC, a resistor (about 310 Ω) must always be connected to VCC and the power supply pin of the drive circuit. If VCC2 is connected to VCC without a resistor, the IC may be damaged by overcurrent when operating in a voltage range close to the maximum operating voltage.

(2) Control signal waveform

The rise and fall time pins of the signal applied to the controller should be 5ms or less. A longer time will cause unstable operation of the internal logic circuit and may result in damage to the driver circuit.

For example, if an externally controlled supply voltage circuit rises after the IC supply voltage, the rising edge of the control signal slowly follows the rising external supply voltage. This can lead to unstable IC operation or damage due to excessive current flow. This should be avoided by detecting the motor running current as shown below.

(4) Input pins

The VCC voltage is not applied to the IC when the voltage should not be applied to the input pins. Likewise, when VCC is applied, the voltage on each input pin should be below VCC and within guaranteed electrical characteristics.

(5) Recoil voltage

The kickback voltage may fluctuate depending on environmental conditions, environmental or motor characteristics. Be sure to confirm that the kickback voltage does not adversely affect the operation of the IC.

(6) High current line

High current is carried by the motor power supply to the motor ground of these ICs. Therefore, the pattern layout of the PC board and the constants of certain parameters of external components, such as capacitors between power supplies and ground, can cause this large output current to flow back to the input pins, causing output oscillations or other malfunctions. To prevent this, make sure that the PC board layout and external circuit constants do not cause

There are problems with the characteristics of these ICs.

(7) Power consumption

Power consumption fluctuates with the mounting conditions of the IC and the surrounding environment. Be sure to carefully review the thermal design of applications using these ICs.

(8) Power consumption

The power consumption of an IC varies greatly with IC supply voltage and output current. Provide thermal design so that the rating of the IC is not exceeded, taking into account the power dissipation rating and thermal resistance data and transient thermal resistance data.

(9) ASO

Make sure that the output current and supply voltage do not exceed the ASO value.

(10) Precautions for input mode switching To ensure reliability, it is recommended to use this mode to switch the motor through one turn on mode.

(11) The circuits built into these ICs cannot prevent surge currents. Therefore, placing current limiting resistors or other physical countermeasures is recommended.

(12) If the potential of the output pin fluctuates greatly and is lower than the ground potential, the operating IC may malfunction or be adversely affected. In such cases, put a diode between the output and ground, or something to prevent this.

(13) The quality of these products has been carefully considered for inspection; however, use of products with applied voltage, operating temperature, or other parameters exceeding the given absolute maximum ratings may result in damage to the IC and the products it uses. If the IC is damaged, short die and open die cannot. If the IC is to be used in an application, specify parameters that may exceed the absolute maximum rating, then be sure to incorporate fuses or other physical safety measures.

Application example diagram

Dimensions (unit: mm)