L9942 Datasheet, PDF (1/37 Pages) STMicroelectronics – Integrated stepper motor driver for bipolar stepper motors with microstepping and programmable current profile

L9942
Integrated stepper motor driver for bipolar stepper motors
with microstepping and programmable current profile
PRELIMINARY DATA
Features
■ Two full bridges for max. 1.3 A load (R_DSON =
500 mΩ)
■ Programmable current waveform with look-up
table: 9 entries with 5bit resolution
■ Current regulation by integrated PWM
controller and internal current sensing
■ Programmable stepping mode: Full, Half, Mini
and Microstepping
■ Programmable slew rate for EMC and power
dissipation optimisation
■ Programmable Fast-, Slow-, Mixed-and Auto-
Decay Mode
■ Full-Scale Current programmable with 3bit
resolution
■ Very low current consumption in standby mode
I_S < 3µA, typ. T_j ≤ 85 °C
■ All outputs short circuit protected with
Openload, Overloadcurrent, Temperature
Warning and Thermal Shutdown
■ The PWM signal of the internal PWM controller
is available as digital output.
■ All parameters guaranteed for 7V < Vs < 20V
Applications
Stepper Motor Driver for bipolar Stepper Motors in
Automotive Applications like Light Levelling,
Bending Light and Throttle Control.
PowerSSO-24
Description
The device is an integrated stepper motor driver
for bipolar stepper motors with microstepping and
programmable current profile look-up-table to
allow a flexible adaptation of the stepper motor
characteristics and intended operating conditions.
It is possible to use different current profiles
depending on target criteria: audible noise,
vibrations, rotation speed or torque. The decay
mode used in PWM-current control circuit can be
programmed to slow-, fast-, mixed-and auto-
decay. In autodecay mode device will use slow
decay mode if the current for the next step will
increase and the fast decay or mixed decay mode
if the current will decrease.
Order codes
Part number
L9942
Junction Temp range, °C
-40 to 150
Package
PowerSSO-24
Packing
Tube
November 2005
This is preliminary information on a new product now in development or undergoing evaluation. Details are subject to
change without notice.
Rev 1
1/37
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