STMicroelectronics L9177A

The L9177A is an automotive engine management control IC designed by STMicroelectronics, utilizing their proprietary BCD technology. This device is tailored to control 2-cylinder internal combustion engines in low-end applications such as small motorcycles, K-cars, and nautical engines. It integrates a comprehensive set of power supplies and signal preprocessing peripherals necessary for engine control.

The L9177A includes multiple voltage regulators, injector drivers, relay drivers, a stepper motor driver, and an O2 sensor heater, all of which can be controlled via parallel input or SPI interface. The device also features a variable reluctance sensor interface and a K-line transceiver for data communication, adhering to the ISO-9141 standard.

It is packaged in a TQFP64 10x10 mm package with an exposed pad for optimized power dissipation and is AEC-Q100 qualified, ensuring reliability in automotive environments.

• AEC-Q100 qualified for automotive reliability
• Supply voltage range from 6 V to 18 V, with basic functionality guaranteed down to 3.9 V
• 5 V main voltage regulator up to 300 mA with thermal shutdown protection
• 5 V tracking regulator up to 40 mA and short to battery protection
• 5 V standby regulator up to 2.5 mA
• Two channels of injector drivers, two relay drivers, and one additional relay driver controlled by SPI
• Stepper motor driver for double winding coil motor, used for engine idle speed control
• Low side drivers with SR control to minimize emission
• Protected 50 mA high side driver
• Variable Reluctance Sensor interface for crank angle measurement
• K-line transceiver (ISO-9141 compatible) for data communication
• Full diagnosis via 24-bit SPI interface, including over-temperature protection
• Microcontroller reset logic and self-configuring variable reluctance sensor interface

The L9177A is designed for use in various low-end automotive and non-automotive internal combustion engine applications, including:

• Small motorcycles
• K-cars
• Nautical engines
• Other small engine applications requiring advanced power management and signal preprocessing

1. What is the primary function of the L9177A?

   The L9177A is an automotive engine management control IC designed to provide the full set of power supplies and signal preprocessing peripherals needed to control 2-cylinder internal combustion engines.

2. What are the key voltage regulators integrated into the L9177A?

   The device includes a 5 V main voltage regulator, a 5 V tracking regulator for sensor supply, and a 2.5 mA 5 V standby regulator.

3. How are the injector drivers and relay drivers controlled?

   The two channels of injector drivers, the O2 sensor heater, and two relay drivers can be controlled both with parallel input and with SPI interface. One additional relay driver and the current limited low side driver are controlled by SPI.

4. What is the purpose of the stepper motor driver in the L9177A?

   The stepper motor driver is designed for a double winding coil motor, used for engine idle speed control.

5. Does the L9177A have any diagnostic capabilities?

   Yes, the device provides full diagnosis via a 24-bit SPI interface, including diagnostics for injector drivers, relay drivers, O2 sensor heater, tachometer, and stepper motor driver, as well as general diagnostic for over-temperature.

6. What is the operating temperature range of the L9177A?

   The operating temperature range is from -40°C to 150°C.

7. Is the L9177A AEC-Q100 qualified?

   Yes, the L9177A is AEC-Q100 qualified, ensuring its reliability in automotive environments.

8. What package type is the L9177A available in?

   The device is available in a TQFP64 10x10 mm package with an exposed pad for power dissipation optimization.

9. What data communication interface does the L9177A support?

   The L9177A supports a K-line transceiver, which is ISO-9141 compatible.

10. Does the L9177A have any protection against over-temperature?

    Yes, the device includes overall protection against over-temperature.