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PDA 05 5/30/03 11:35 AM Page 97
Figure 5.41
L298 packages. Chapter 5 / The Electronics

Description
The L298 is an integrated monolithic circuit in 15-lead Multiwatt and
PowerSO20 packages. It is a high-voltage, high-current, dual full-bridge
driver designed to accept standard TTL logic levels and drive inductive
loads such as relays, solenoids, DC, and stepping motors. Two enable
inputs are provided to enable or disable the device independently of
the input signals. The emitters of the lower transistors of each bridge
are connected together, and the corresponding external terminal can be
used for the connection of an external sensing resistor.
An additional supply input is provided so that the logic works at a
lower voltage, as is the case in PDA Robot. The logic supply comes
from the 5 V regulator on the main board via the ribbon connector and
the power supply, which drives the motors directly from the 6 V bat-

Figure 5.42
L298 block diagram.

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