DC brushed motor IC with current limit detection

All of these devices have grown rapidly in popularity in recent years and usually incorporate DC brushed motors. Until now the safe control of DC brushed motors has been accomplished by limiting the upper value of the motor current through a constant current limit. The over current is generated by the motor lock and is read from an external resistor through external circuitry that consists of operational amplifiers and comparators, thereby increasing the component count and circuit complexity.

The highly integrated TB67H401FTG is fabricated with Toshiba’s BiCD process and has an inbuilt flag output circuit, which monitors the current state and indicates that the current has reached the upper threshold. As this function is now included, the external circuitry is no longer required and motor solutions are smaller, more efficient and have reduced BOM costs.

The TB67H401FTG supports a total of four drive modes; forward (CW), reverse (CCW), brake (short brake) and stop (off). The new driver IC also includes a mode switching function that extends the range of possible applications. The single-bridge mode supports a single channel current up to 6.0A and a dual-bridge mode allows the use of two motors with a single IC driving up to 3.0A per motor.

The low on-resistance MOSFETs incorporated into the H-bridge (High side + Low side =0.49Ω typ.) ensure low losses and efficient operation. Due to an internal 5V regulator, the device can be driven from a single power supply.

The tiny device is housed in a 7x7x0.9mm QFN48 package and also includes thermal shutdown detection, over current protection and under voltage lockout. A general error detection signal enhances system safety by providing a warning to the main system controller.

The TB67H401FTG is ready for mass production.