LSI Computer Systems Unveils LS7290 Precision Stepper Motor Controller

LSI/CSI announces the availability of its new high performance stepper motor controller integrated circuit, designated LS7290. “A huge advantage for our customers is that the low cost LS7290 can replace the expensive L297 in most applications while providing more programmable micro-steps,” according to Pete Visconti, VP Sales and Marketing. This new IC is capable of a large selection of step sizes ranging between full and 1/32 step.

The LS7290 is designed to control two-phase bipolar stepper motors or four-phase unipolar stepper motors with minimum burden on the resources of a host micro-controller. For bipolar motors, the LS7290 interfaces with an external Dual Full Bridge Driver such as the L298, which contains a pair of H- bridges driven by the LS7290 PWM and Phase Control outputs. The H-bridges allow for the selection of wide range of motor sizes. For unipolar motors, the LS7290 PWM and Phase Control outputs interface with four AND gates driving four NMOS driver transistors.

Inputs to the LS7290 are available to control the step size, step command, motor direction, over-current sense, over-current threshold and inter-step phase drive blanking delays. The programmable inter-step blanking delays allow for delay selection to suit a specific motor resulting in reduced audible motor noise, increased step accuracy, and reduced power dissipation. The basic timing clock can be supplied either from the built-in oscillator or from the system clock.

LS7290 features include:

  • Programmable step sizes: full, 1/2, 1/4, 1/8, 1/16 and 1/32
  • Nominal clock frequency: 8MHz
  • Maximum stepping rate: greater than 30k per second
  • Programmable inter-step blanking delays: 1.25us, 2.5us, 3.75us, and 5us at 8MHz
  • H-bridge PWM resolution: 0.39%
  • Supply voltage: 3V to 5.5V

LS7290 is available in 24-pin DIP, SOIC and TSSOP packages. Pricing at 1,000 pieces is $1.15.

In addition to its line of stepper motor controllers, brushless DC motor controls and other standard product ICs, LSI/CSI has been producing turnkey, mixed-signal full custom ICs for a broad range of industries since 1969.

About LSI Computer Systems, Inc.
LSI Computer Systems, Inc. (LSI/CSI) began operations as the world’s first fabless semiconductor company in 1969. Since its inception, LSI/CSI has been a leader in the design and production of affordable full custom and standard mixed signal, digital and analog integrated circuits. Using a broad array of process technologies, LSI/CSI has produced ICs that extend from the consumer and industrial marketplace to military and aerospace applications.