L9942 Integrated stepper motor driver for bipolar stepper motors with microstepping and programmable current profile Features Two full bridges for max. 1.3 A load (R = 500 m ) DSON Programmable current waveform with look-up table: 9 entries with 5 bit resolution Current regulation by integrated PWM controller and internal current sensing Programmable stepping mode: full, half, mini and microstepping PowerSSO24 Programmable slew rate for EMC and power dissipation optimization Programmable Fast-, Slow-, Mixed- and Auto- Decay Mode Description Full-scale current programmable with 3 bit resolution The L9942 is an integrated stepper motor driver Programmable stall detection for bipolar stepper motors with microstepping and programmable current profile look-up-table to Step clock input for reduced Controller allow a flexible adaptation of the stepper motor requirements characteristics and intended operating conditions. Very low current consumption in standby mode It is possible to use different current profiles I < 3 A, typ. T 85 C S j depending on target criteria: audible noise, All outputs short circuit protected with vibrations, rotation speed or torque. The decay openload, overload current, temperature mode used in PWM-current control circuit can be warning and thermal shutdown programmed to slow-, fast-, mixed-and auto- The PWM signal of the internal PWM controller decay. In autodecay mode device will use slow is available as digital output. decay mode if the current for the next step will increase and the fast decay or mixed decay mode All parameters are guaranteed for 3 V < Vcc < if the current will decrease. The programmable 5.3 V and for 7 V < Vs < 20 V stall detection is useful in case of head lamp leveling and bending light application, by Applications preventing to run the motor too long time in stall for position alignment. If a stall is detected, the Stepper motor driver for bipolar stepper motors in alignment process is closed and the noise is automotive applications like light levelling, minimized. Bending light and Throttle control. Table 1. Device summary Order code Junction temp. range, CPackage Packing L9942XP1 -40 to 150 PowerSSO24 Tube L9942XP1TR -40 to 150 PowerSSO24 Tape and reel September 2013 Doc ID 11778 Rev 7 1/40 www.st.com 1Contents L9942 Contents 1 Block diagram and pin information . 6 2 Device description 9 2.1 Dual power supply: V and V S CC 9 2.2 Standby mode 9 2.3 Diagnostic functions 9 2.4 Overvoltage and undervoltage detection 9 2.5 Temperature warning and thermal shutdown 10 2.6 Inductive loads . 10 2.7 Cross-current protection 10 2.8 PWM current regulation 10 2.9 Decay modes 10 2.10 Overcurrent detection 11 2.11 Open load detection . 11 2.12 Stepping modes 11 2.13 Decay modes 13 3 Electrical specifications . 14 3.1 Absolute maximum ratings 14 3.2 ESD protection . 14 3.3 Thermal data 15 3.4 Electrical characteristics 16 3.4.1 Supply 16 3.4.2 Over- and undervoltage detection . 17 3.4.3 Reference current output 17 3.4.4 Charge pump output . 18 3.4.5 Outputs: Qxn (x = A B n = 1 2) 18 3.4.6 PWM control . 20 4 Functional description of the logic with SPI . 21 4.1 Motor stepping clock input (STEP) 21 4.2 PWM output (PWM) . 21 4.3 Serial peripheral interface (SPI) 21 2/40 Doc ID 11778 Rev 7