Basic Info.

Product Description

Feature ?± 2.5 ma rate of 35 v output ?low rds (on) output (typically 0.45 eu source, 0.36 euro sink) ?since the drive current decay mode detection / selection ?3.0 to 5.5 v logic supply voltage range ?mixed fast and slow current - decay mode ?auto-oriented output ?synchronous rectification for low power dissipation ?internal under voltage lockout (uvlo) and thermal shutdown circuit ?cross-current protection description a3977sed and a3977slp are two complete micro stepping motor driver with built-in converter. both in whole, 1 / 2, 1 / 4 and 1 / 8 step modes operate bipolar stepper motors, the output drive capability of 35 v and ± 2.5 amps. a3977 includes a fixed off-time current regulator; the regulator is in low, fast or mixed decay modes. this current decay control scheme results in reduced audible motor noise, increased step accuracy and reduced power dissipation. converter is the key to the easy implementation of a3977. simple in the "step" input, enter a pulse, the motor will have step (full, 1 / 2, 1 / 4 or 1 / 8 step, according to the two logic inputs of the case may be). there are no phase sequence tables, high frequency control lines or complex interfaces. a3977 interface is ideal for complex µp is unavailable or is overburdened. internal synchronous rectification control circuitry is used to improve the pulse-width modulation (pwm) operation of the power consumption.