L298N芯片手册完成版.pdf

APPLICATION NOTE HIGH-POWER, DUAL-BRIDGE ICs EASE STEPPER-MOTOR-DRIVE DESIGN In addition to simplifying design problems, a family of dedicatedchips improves stepper-motordrive-circuit reliability by significantly reducing the component count. The L293, L293E and L298N dual-bridge ICs (see constant-current choppers. And with a single chip box, ”inside the dual-bridge ICs”) significantly redu- replacing the transistors and predriver stages, cir- ce the problems encountered in the design of step- cuit performance improves. Best of all, the devices per-motor drive circuitry. They can, for example, have applications in complex as well as basic driver simplify the design and increase the efficiency of networks. Figure 1 : The Simplest Stepper-motorDrive Technique is the Basic L/R Configuration. AddingSeries Re- sistors and Raising the Supply to Make an L/4R Drive Improves Torque at High Steps rates but Reduces Efficiency. AN238/0488 1/8 APPLICATION NOTE SIMPLEST DESIGN IS AN L/R DRIVE useandL298N).However,if youplanto run the mo- tor continuouslywith two phases on, dissipationwill The simplest motor-drive configuration (fig. 1) con- be the limiting factor. sists of a µC that performs the translator function in software (see box, ”Generating switching sequen- You can improve the performance of this basic L/R ces”) and drives the motor througha L293dual brid- drive by increasing the series resistanceand raising