Automotive door-zone and rear-window controller

STMicroelectronics is increasing the integration of automotive body electronics with the L99DZ200G door-zone system IC, which has been developed to enable a single-chip front-drives-rear setup managing a front-door window, mirror, and lighting as well as the rear-window lift.

These features deliver a set of benefits including lower system quiescent current, greater reliability, faster assembly, reduced bill of materials, and shorter development time.

The L99DZ200G contains two H-bridge gate drivers, a gate driver for an external MOSFET to control mirror heating, a control block and high-side driver for electro-chromic mirror dimming, and five LED high-side drivers. Three of the high-side drivers can operate in constant-current mode to power lighting modules that have high input capacitance. The other two high-side drivers are suitable for controlling ordinary LEDs.

With its two H-bridge drivers, the L99DZ200G can control two spindle motors simultaneously and handle an additional cinch motor to close a powered tailgate or trunk. Both drivers allow operation in generator mode, which activates both low-side MOSFETs simultaneously to protect the device if an overvoltage is detected in the supply rail.

The L99DZ200G also provides power management, with two 5V low-dropout regulators for the host microcontroller and peripherals. Connections for control and communication include a LIN 2.2a (SAEJ2602, SAE J2962-1) transceiver, High-Speed CAN (HS-CAN, ISO 11898-2:2003 /-5:2007, SAE J2284, SAE J2962-2) transceiver, and SPI 4.0 interface.

Diagnostic and protection features include temperature monitoring and thermal protection, a dedicated failsafe block to pull down the gates of the external high-side MOSFETs, and open-load and overcurrent detection for all outputs. A current-monitor output pin is provided for each high-side channel. Overcurrent recovery and thermal expiration allow operation to resume automatically after a fault. There is also reverse-battery protection and system-safety features including a configurable window watchdog and programmable reset generator.