E-L9935 STMicroelectronics

L9935 Two-phase stepper motor driver Features 2 x 1.1 A full bridge outputs Integrated chopping current regulation Minimized power dissipation during flyback 0 03 Output stages with controlled output voltage slopes to reduce electromagnetic radiation PowerSO20 Short-circuit protection of all outputs Error-flag for over load, open load and over temperature pre alarm Delayed channel switch on to reduce peak Description currents The L9935 is a two-phase stepper motor driver Max. operating supply voltage 24 V circuit suited to drive bipolar stepper motors. Standby consumption typically 40 A The device can be controlled by a serial interface Serial interface (SPI) (SPI). All protections required to design a well protected system (short-circuit, over temperature, cross conduction etc.) are integrated. Table 1. Device summary Order code Package Packing L9935 PowerSO20 Tube L9935013TR PowerSO20 Tape and reel September 2013 Doc ID 5198 Rev 10 1/29 www.st.com 1Contents L9935 Contents 1 Block diagram 6 2 Pin description . 7 3 Electrical specifications 8 3.1 Absolute maximum ratings . 8 3.2 Thermal data . 8 3.3 Electrical characteristics . 9 4 Application hints . 11 5 Functional description 12 5.1 Basic structure . 12 5.2 Full bridge function 13 5.2.1 No current . 13 5.2.2 Turning on . 13 5.2.3 Chopping 13 5.2.4 Reversing phase 14 5.2.5 Chopper control by oscillator . 14 5.3 Protection and diagnosis functions 15 5.4 Short from an output to the supply voltage V S . 15 5.5 Diagnosis of a short to V S . 16 5.6 Short from an output to ground 17 5.7 Diagnosis of a short to ground . 17 5.8 Shorted load . 17 5.9 Diagnosis of a shorted load . 17 5.10 Open load . 17 5.10.1 Over temperature pre alarm . 18 5.11 Application hints using a high resistive stepper motor . 18 5.11.1 Startup behavior 18 5.12 Limitation of the diagnosis 19 5.13 Serial data interface (SPI) 19 5.13.1 Startup of the serial data interface . 20 2/29 Doc ID 5198 Rev 10