L99SM81V Programmable stepper motor driver for automotive applications with micro-stepping and stall detection Datasheet - Production data 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 Features measurement and stall detection 5 V low drop voltage regulator short-circuit protected AEC-Q100 qualified Very low current consumption in standby Stepper motor driver with up to 1.35 A mode (typ. 10 A) current capability Thermal warning and shutdown Programmable Step mode: ST SPI 4.1 interface for control and Full step, Half step, Mini step, 1/8 Micro diagnostics step, 1/16 Micro step Current regulation by integrated PWM Applications control with fully integrated current sensing Equivalent 10 bit resolution on current Bipolar 2 phase stepper motor driver for regulation loop: automotive applications like adaptive front light Two 4-bit programmable full scale systems or projectors for head-up displaying current amplitudes: one for RUN and one for HOLD mode Description 6-bit DAC for reference current The L99SM81V is an automotive grade generation (whatever programmed full integrated driver for bipolar two-phase stepper scale amplitude) motors capable of current controlled micro- 4 programmable decay modes: stepping with programmable amplitude. The Slow-mode, mixed-mode and 2x device features a 5 V voltage regulator to supply automatically selected decay-modes external sensors. 3x programmable inputs for direct control of step clock, direction, hold and step modes The integrated Serial Peripheral Interface (SPI) makes it possible to adjust device parameters, 1x programmable analog output for Tj control all operating modes and read out measurement or band-gap reference diagnostic information. Digital I/Os are also 2x programmable digital outputs for optionally usable for more flexible and reliable internally generated PWM ON duty cycles, application control. June 2017 DocID027599 Rev 4 1/85 www.st.com This is information on a product in full production. Contents L99SM81V Contents 1 Block diagram and pin description ................................................ 8 2 Device description ......................................................................... 11 2.1 Supply pins (VS, VREG, VDD) ........................................................ 11 2.2 Voltage regulator (V5V) ................................................................... 11 2.3 Charge Pump (CP) .......................................................................... 11 2.4 Standby mode (EN) ......................................................................... 11 2.5 Application block diagram ............................................................... 12 2.6 Stepping modes and step update .................................................... 12 2.7 Current references generation and PWM regulation ....................... 16 2.8 HOLD mode .................................................................................... 17 2.9 Decay modes .................................................................................. 17 2.9.1 DMR 1:0 bits = 01b, DMH = 0 - Slow decay mode always applied . 18 2.9.2 DMR 1:0 bits = 10b, DMH = 1 - Mixed decay mode always applied .. 19 2.9.3 DMR 1:0 bits = 00b - Auto decay mode 1 ....................................... 21 2.9.4 DMR 1:0 bits = 11b - Auto decay mode 2 ....................................... 24 2.10 Control pins (CTRLx) ...................................................................... 26 2.10.1 Step Control (STEP) ......................................................................... 26 2.10.2 Direction Control (DIR) ..................................................................... 26 2.10.3 Step mode Control (SMODE) and HOLD mode ............................... 26 2.11 Digital outputs ................................................................................. 27 2.11.1 Error/ warning indicator (ERR) ......................................................... 27 2.11.2 Error/ warning change indicator (EC) ............................................... 27 2.11.3 PWM ................................................................................................. 28 2.11.4 Coil Voltage Conversion Ready (CVRDY) ....................................... 28 2.11.5 Coil Voltage Runaway (CVRUN) ...................................................... 28 2.11.6 Coil Voltage Lower Limit Underrun (CVLL) ...................................... 28 2.12 Analog output .................................................................................. 28 2.13 Motor coil voltage measurement for stall detection ......................... 29 2.13.1 Coil voltage measurement triggering ................................................ 30 2.13.2 Coil voltage measurement processing ............................................. 30 2.14 Serial peripheral interface (ST SPI standard) .................................. 31 3 Protections and diagnostics ......................................................... 33 3.1 Supply diagnostics .......................................................................... 33 3.1.1 VS overvoltage and undervoltage .................................................... 33 2/85 DocID027599 Rev 4