SLA7077MS

Overview

The SLA7077MS is a two-phase unipolar stepper motor driver from the Sanken Electric SLA707xM series, housed in a 23-pin power multi-chip module. It integrates low-power CMOS logic with high-current, high-voltage NMOS power FET outputs to provide complete control and drive for stepper motors. The device supports full, half, quarter, eighth, and sixteenth-step operation via external selection. Key electrical specifications include a maximum motor supply voltage (VM) of 44V, a load supply voltage (Vs) range of 10V to 44V, and a logic supply voltage (Vcc) of 3V to 5.5V. The outputs are capable of sinking up to 3A and withstanding 46V in the off state.

Feature Summary

• Integrates CMOS sequencing logic with high-current NMOS power outputs for direct stepper motor control
• Supports externally selectable micro-stepping modes including full, half, quarter, eighth, and sixteenth steps
• Features internal fixed off time and pulse-width modulation (PWM) current control
• Includes clamp diodes for protection against inductive transients

Applications

• Personal Computer Peripherals (PPC)
• Printers
• Office Automation Equipment

Procurement Notes

Verify the specific suffix 'MS' against the official Sanken Electric datasheet to confirm pinout compatibility and thermal characteristics. Ensure the application circuit provides appropriate pull-up resistors if using TTL or LSTTL logic inputs to guarantee proper logic high levels. Confirm that the system design accommodates the 23-pin package requirements and that the reference voltage and sensing resistor selections align with the desired maximum output current limits.

Selection Notes

Select this component when driving two-phase unipolar stepper motors requiring multiple micro-stepping resolutions beyond standard half-step operation. It is suitable for systems where complex microprocessors are unavailable or overloaded, as it handles sequencing internally. Choose this part over lower-current variants if the application demands up to 3A sink capability. Ensure the logic interface matches the 3V to 5.5V Vcc range and that the motor supply voltage does not exceed 44V.

Part Context

The SLA7077MS belongs to the SLA707xM family of 2-Phase Unipolar Stepper Motor Drivers manufactured by Sanken Electric. This series combines CMOS logic with power FET outputs in a single PMCM package. While the SLA7070/71/72/73MR models support only full and half-step operations, the SLA7075/76/77/78MR variants, including the SLA7077MS, offer additional externally selectable quarter, eighth, and sixteenth-step capabilities for smoother motor motion.

Replacement Considerations

Compatible substitutes within the same series include SLA7075MS, SLA7076MS, and SLA7078MS, which share similar packaging and functional architectures but may differ in specific current ratings or step-resolution defaults. Verify pin-to-pin compatibility and thermal performance before substitution.