Automotive high-side drivers with built-in intelligence

September 22, 2021 // By Christoph Hammerschmidt
Automotive high-side drivers with built-in intelligence
The VN9D30Q100F and VN9D5D20FN devices from STMicroelectronics are, according to the manufacturer, the first representatives of a new generation of intelligent switches for the automotive sector. For the first time on the market, they offer digital current measurement in addition to purely digital, chip-integrated diagnostic features. They simplify hardware and software design for electronic control units (ECUs) and improve system reliability.

Based on the latest generation of ST's VIPower M0-9 technology, the devices combine a 40V vertical trench MOSFET with 3.3V digital logic and high-precision analogue circuitry in a 6 mm x 6 mm QFN package. The compactness and high level of integration provide a 40% reduction in board space compared to similar driver ICs on the market.

The VN9D30Q100F has two 33mΩ (milli-Ohm) and two 99mΩ channels, while the VN9D5D20FN has two 7.6mΩ and two 20mΩ channels. Each of the devices has up to six output channels with SPI interface, reducing the number of I/O pins on the microcontroller required to interact with the driver. In addition, the devices are equipped with an integrated PWM (pulse width modulator) generator with a resolution of 0.1%, which can provide a purposeful, precise control signal at each output for functions such as dimming lights. The drivers are designed for high-side connection in applications for the 12 V vehicle electrical system.

Diagnostic circuitry includes an always-on A/D converter (ADC) with 10-bit resolution and 5% accuracy that outputs load current and enclosure temperature in digital form, so no ADC in the host microcontroller is needed for this. The ADC task manager is synchronised with the driver's PWM unit to ensure that diagnostics are automatically run at the correct time for each output channel without any intervention from the microcontroller. There are also two OTP (One-Time Programmable) inputs for operation in emergency mode when there is no longer any control from the host microcontroller due to a system failure.

In addition to reducing hardware costs by minimising power dissipation and board complexity, the new drivers also simplify Autosar compliance by providing a complex driver that operates independently of the application, thereby facilitating software development.


Vous êtes certain ?

Si vous désactivez les cookies, vous ne pouvez plus naviguer sur le site.

Vous allez être rediriger vers Google.