NJU7385

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FUNCTION DESCRIPTION

Auto Standby Function

The device can be used for mobile equipments that require batteries. When STB terminal turns to “L”, Standby State1 is

achieved. On the other hand, 4 terminals (IA1A/1B,IN2A/2B) are set to “L”, Standby State2 is achieved, which is unique

from other devices. When in Standby State, the device stands by under minimum power consumption.

UVLO Function

UVLO function goes into action when VDD is less than 1.8V (typ.). In the event of low VDD, UVLO circuit disables the

drivers (OUT1A/2A & OUT1B/2B), and simultaneously sets the ALARM output terminal to “L”.

TSD Function

TSD function goes into action when Tj is more than 170

°C (typ.). In the event of high Tj, TSD circuit disables the drivers

(OUT1A/2A & OUT1B/2B), and simultaneously sets the ALARM output terminal to “L”.

ALARM Output Function

In the event of fault conditions (UVLO, or TSD active), the device sets the ALARM output terminal to “L” to provide

indication of fault conditions.

At the same time, output terminals for Motor (OUT1A/2A & OUT1B/2B) are disabled to prevent damage and

unpredictable device operation.

STB: Power Saving State Setting Terminal

STB set to “L” puts the device in Standby State1. It is a similar condition with Auto Standby State (Standby State2).

MS: Input Control Mode Setting Input Terminal

MS

Input Control Mode

L

2-Input Control

H

Phase & Enable Input Control

MS is used to toggle between 2-Input Control and Phase & Enable Input Control.

<The features of 2-Input Control>

When MS terminal turns to “L”, 2-Input Control is selected.

One of the features is: 4 Half-Bridges are controlled independently because the input and output is in a one-to-one

ratio. (IN1A-OUT1A, IN1B-OUT1B, IN2A-OUT2A, IN2B-OUT2B)

This input mode is relatively suitable for DC Motor applications.

In case of one-way rotation and braking control, it is possible to control 4 DC Motors at the same time.

Additionally, in case of using of H-Bridge control, it is available to be achieved precision current control around Zero

cross current area by using complementary PWM with PWM-duty control at IA1A/1B&IN2A/2B terminals.

<The features of Phase & Enable Input Control>

When MS terminal turns to “H”, Phase & Enable Input Control is selected.

The logic level of IN1A/IN2A corresponding to Phase-function decides current direction in H-Bridge control.

IN1B/IN2B correspond to Enable-function. When IN1B/IN2B are set to “L”, the drivers (OUT1A/2A & OUT1B/2B) are

disabled.

This input mode is relatively suitable for Stepper Motor applications. It is possible to control Half-Step-Mode that

needs making the drivers disabled.

Additionally, in case of Full-Step-Mode, it is available to be achieved a simple control of Stepper Motor using only 2

wires to IN1A/IN2A.