Features
 AEC-Q100 qualified
 Stepper motor driver with up to 1.35 A
current capability
 Programmable Step mode:
 Full step, Half step, Mini step, 1/8 Micro
step, 1/16 Micro step
 Current regulation by integrated PWM
control with fully integrated current sensing
 Equivalent 10 bit resolution on current
regulation loop:
 Two 4-bit programmable full scale
current amplitudes: one for RUN and
one for HOLD mode
 6-bit DAC for reference current
generation (whatever programmed full
scale amplitude)
 4 programmable decay modes:
 Slow-mode, mixed-mode and 2x
automatically selected decay-modes
 3x programmable inputs for direct control of
step clock, direction, hold and step modes
 1x programmable analog output for Tj
measurement or band-gap reference
 2x programmable digital outputs for
internally generated PWM ON duty cycles,
error signals, coils voltage measurement
synchronization signals
 Programmable MOSFETs switching speed:
four options for EMC and power dissipation
trade-off optimization
 PWM frequency wobbling for reduction of
conducted EM energy
 Outputs protection and diagnosis (open
load, short to battery, short to GND)
 Integrated ADC for coil voltage
measurement and stall detection
 5 V low drop voltage regulator short-circuit
protected
 Very low current consumption in standby
mode (typ. 10 μA)
 Thermal warning and shutdown
 ST SPI 4.1 interface for control and
diagnostics

Description
The L99SM81V is an automotive grade
integrated driver for bipolar two-phase stepper
motors capable of current controlled microstepping
with programmable amplitude. The
device features a 5 V voltage regulator to supply
external sensors.
The integrated Serial Peripheral Interface (SPI)
makes it possible to adjust device parameters,
control all operating modes and read out
diagnostic information. Digital I/Os are also
optionally usable for more flexible and reliable
application control.

Applications
Bipolar 2 phase stepper motor driver for
automotive applications like adaptive front light
systems or projectors for head-up displaying