Description
The L9958 is an SPI controlled H-Bridge, designed for the control of DC and stepper motors in safety critical applications and under extreme environmental conditions. The H-Bridge is protected against over temperature, short circuits and has an undervoltage lockout for all the supply voltages Vs and Vdd, and for overvoltage on Vdd. All malfunctions cause the output stages to go tristate. Detailed failure diagnostics on each channel is provided via SPI: short circuit to battery, short circuit to ground, short circuit overload, over temperature. Open-load can be detected in ON condition, for the widest application ranges. Current regulation threshold can be set by SPI from 2.5 A to 8.6 A (Typ.), in 4 steps. Guaranteed accuracy is ±10 % on all temp range, using an external reference resistor with 1% accuracy over all temp range. Current limitation threshold is linearly reduced by temperature over 165 °C.and a thermal warning bit is set by SPI. The H-Bridge contains integrated free-wheel diodes. In case of free-wheeling condition, the low side transistor is switched on in parallel of its diode to reduce power dissipation. A multiple wire bonding technique, as well as ST proprietary package design is making L9958 compatible with three power packages, for maximum flexibility: PowerSO-20 package (medium power, JEDEC standard MO166); PowerSO16 package (medium power, lower cost); PowerSSO24 package (low power, very low cost JEDEC standard MO271A).

Features
■ Programmable current regulation peak threshold by SPI up to 8.6 A typ.
■ Operating battery supply voltage 4.0 V to 28 V
■ Operating Vdd supply voltage 4.5 V to 5.5 V
■ All pins withstand 19 V, Vs and output pins withstand 40 V
■ Full path Ron from 100 mΩ (at Tj = -40 °C) to 300 mΩ (at Tj =150 °C)
■ Logic inputs TTL/CMOS-compatible
■ Operating frequency up to 20 kHz
■ 16-bit SPI interface for configuration/diagnostics, daisy chain capability
■ Over temperature and short circuit protection
■ VS undervoltage disable function
■ Vdd undervoltage and overvoltage protection
■ Vdd overvoltage detection
■ Open-load detection in ON condition
■ Full diagnostics in OFF state
■ Enable and disable input
■ Low stand by current (<10 µA)
■ Voltage and current slew-rate control for low EMI, programmable through SPI
■ Available in three power packages