H-bridge Driver IC Supporting 1.8V Low-Voltage and 4.0A Current Drive

Toshiba Electronic Devices & Storage Corporation has announced the launch of the TC78H653FTG, an addition to its line-up of dual-H-bridge driver ICs for dc brushed motors and stepping motors that delivers the low voltage (1.8V) and high current (4.0A) essential for low voltage equipment powered by dry-cell batteries, such as mobile devices, electronic products for the home and USB drives.

The TC78H653FTG is designed for use in motor applications driven by relatively low voltage batteries (1.8V to 7.0V), mobile devices (cameras, electric toothbrushes, printers) using 3.7V lithium-ion batteries, products for the home, such as electronic locks, smart meters, electronic bidet toilet, and toys using two 1.5V dry batteries, and devices using 5V USB power supply.

In recent years, as IoT advances and wireless technologies find increasingly wide use, demand for applications that can be remotely operated via smartphones and other tools is increasing, and with it interest in battery-powered motor control.

This trend is stimulating demand for driver ICs capable of driving devices even at the low voltage of 1.8V (0.9V × 2 batteries, whose capacity is reduced by discharge though 1.5V, 1.2V, etc. are initial voltages.).

Until now, the mainstream devices have been H-bridge driver ICs constructed with bipolar transistors, which can achieve stable operation at low voltage. However, problems with this include large current consumption that shortens battery life and increase current losses in ICs, and insufficient motor torque, since the voltage applied to the motor is lowered.

Toshiba's new dual-H-bridge driver IC uses Toshiba's specialized DMOS process for low voltage drives to achieve a longer battery life with a stable low voltage operation. Improved motor torque is also realized by reducing IC losses through low on-resistance. The new product is suitable for motor applications driven by relatively low voltage batteries (1.8V to 7.0V).

Main features include:

1. Low current consumption prolongs battery life. (ICC = 0.6mA (typ.) in operation mode when VM = 3.0V and Ta = 25°C; ICC = 0 µA (typ.) in standby mode when VM = 3.0V and Ta = 25°C)
2. Low on-resistance reduces IC losses generated by voltage drops in the motor driver and increases the voltage applied to the motor, contributing to improved motor torque. (Ron = 0.11Ω (typ.) (total of high and low sides in large mode when VM = 5V and Ta=25°C)
3. PWM control at 500kHz is possible by high-speed output switching characteristics (ton = 90ns, Toff = 90ns).

(click on table to enlarge)