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PDA 05 5/30/03 11:35 AM Page 102
inputs, or to provide overcurrent protection by switching the enable
input to low. PDA Robotics
The brake function (Fast motor stop) requires that the absolute maxi-
mum rating of 2 amps must never be overcome. When the repetitive
peak current needed from the load is higher than 2 Amps, a paralleled
configuration can be chosen.

An external bridge of diodes is required when inductive loads are
driven and when the inputs of the IC are chopped; Schottky diodes are
preferred. This solution can drive until 3 amps in DC operation and
until 3.5 amps of a repetitive peak current. The L298 is great for driv-
ing a stepper motor. Figure 5.47 shows how this is accomplished
when the current is controlled by a L6506.

Figure 5.47
Two phase bipolar stepper motor control circuit by using the current controller L6506.

The GP2D12 IR Range Finder
The GP2D12 is a low-cost, short-range IR alternative to ultrasonic
range-finding systems. Usable detection range is 10 cm to 80 cm
(approx. 4" to 31.5"). The IR Object Detection System consists of the
Sharp GP2D12 Distance Measuring Sensor. The GP2D12 is a compact,

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