AM2168 datasheet(6/10 Pages) AMTEK

6 / 10 page

AM2168

Motor Driver ICs

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•Logic Control Of Output Current

Two logic level inputs (I0 and I1) allow digital selection of the motor winding current at 100%, 67%, 33%, or 0% of

the maximum level (see table). The 0% output current condition turns OFF all drivers in the bridge and can be used

as an OUTPUT DISABLE function.

Current – Control Truth Table

Output Current

VREF / 10RS = ITRIP

VREF / 15RS = 2/3 ITRIP

VREF / 30RS = 1/3 ITRIP

These logic level inputs greatly enhance the implementation of µP-controlled drive formats.

During half-step operations, the I0 and I1 allow the µP to control the motor at a constant torque between all positions

in an eight-step sequence. This is a accomplished by digitally selecting 100% drive current when only one phase is

ON and 67% drive current when two phases are ON. Logic highs on both I0 and I1 turn OFF all drivers to allow

rapid current decay when switching phases. This helps to ensure proper motor operation at high step rates.

The logic control inputs can also be used to select a reduced current level (and reduced power dissipation) for ‘hold’

conditions and/or increased current (and available torque) for start-up conditions.

AM2168 Datasheet(PDF) 6 Page - AMtek SEMICONDUCTORS CO., LTD