Motor driver ICs Reversible motor driver BA6283N / BA6284N / BA6955N The BA6283N, BA6284N, and BA6955N are reversible-motor drivers with a maximum output current of 1.0 A. Two logic inputs allow four output modes: forward, reverse, stop (standby), and brake. The built-in power save circuit suppresses current consumption in the motor stop mode. Applications VCRs, audio devices Features 1) Logic and driver sections have separate ground pins; this allows the IC to drive speed-variable, reversible motors by connecting an electronic governor circuit. 2) Built-in power saving circuit suppresses current consumption in stop (standby) mode. Absolute maximum ratings (Ta = 25C) Recommended operating conditions (Ta = 25C) 414 3) Interfaces with TTL devices. 4) Built-in thermal shutdown circuit. Motor driver ICs BA6283N / BA6284N / BA6955N Block diagram BA6283N BA6284N BA6955N 415 Motor driver ICs Pin descriptions BA6283N BA6284N BA6955N 416 BA6283N / BA6284N / BA6955N Motor driver ICs BA6283N / BA6284N / BA6955N Input / output circuits 417 Motor driver ICs BA6283N / BA6284N / BA6955N Electrical characteristics (unless otherwise noted, Ta = 25C, VCC = 9V, and VM = 9V) Input / output truth table Application example BA6283N 418 Motor driver ICs BA6283N / BA6284N / BA6955N BA6284N 419 Motor driver ICs Operation notes (1) 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. (2) GND potential The potential for pin 1 must be kept lower than the potentials of the other pins regardless of the circumstances. (3) 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. (4) 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. (5) 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. (6) 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. 420 BA6283N / BA6284N / BA6955N (7) 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. (8) ASO Make sure that the output current and supply voltage do not exceed the ASO values. (9) Precautions for input mode switching To ensure reliability, it is recommended that the mode switching for the motor pass once through the open mode. (10) Rush current There are no circuits built into these ICs that prevent rush currents. Therefore, it is recommended to place a current limiting resistor or other physical countermeasure. (11) 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. (12) Input pins (FIN and RIN) thermal characteristics The FIN and RIN pins have thermal characteristics. Take these thermal characteristics into consideration when using the IC. (13) Thermal shutdown circuit (TSD) When the junction temperature reaches approximately 170C (Typ.) during operation, the driver outputs are all turned off. There is an approximate 20C (Typ.) thermal hysteresis. (14) Motor noise To eliminate motor noise, connect a capacitor between OUT1 and GND and between OUT2 and GND. Alternatively, connect a capacitor between OUT1 and OUT2, and also a diode between OUT1 and GND and between OUT2 and GND (see the figure below). Motor driver ICs BA6283N / BA6284N / BA6955N Electrical characteristic curves 421 Motor driver ICs External dimensions (Units: mm) 422 BA6283N / BA6284N / BA6955N