Toshiba Sends General-purpose Power ICs to the Road for Automotive Safety

December 17, 2019 by Cabe Atwell

The new ICs are available in four versions for automotive applications and feature output voltages that range from 1.1V to 1.5V.

Toshiba has recently announced the release of its new TB9045FNG series—general-purpose system power ICs—that offer multiple outputs for functional safety. The new series comes in output voltages ranging from 1.1V to 1.5V.



TB9045FNG-125. Image from Toshiba

The ICs can operate in temperatures ranging from -40°C to +125°C and are packaged in 6.1mm × 12.5mm × 1.0mm casing. 


Designed for Safety-critical Systems

As vehicle manufacturers continue to incorporate more sophisticated safety-critical systems, such as EPS (Electrical Power Steering) and braking systems, they are required to meet ISO 26262 safety standards. The ICs are designed to support those with the ASIL-D rating—the highest available. 


Reset output system diagram at the time of abnormality detection.

Reset output system diagram at the time of abnormality detection. Image from Toshiba

Toshiba has also incorporated an initial diagnosis circuit, which they claim is capable of detecting latent faults in the failure detection circuits.


Detection Circuits

The TB8045FNG line offers various onboard monitoring circuits for functional safety as well, including:

  • Low-voltage detection circuit for battery power supply
  • High-voltage detection circuit for DC-DC converter (6V)
  • High-voltage/low-voltage detection circuits for the DC-DC converter (1.1V / 1.2V / 1.25V / 1.5V) and series power supply (5V)

They also offer circuits for overheat detection and oscillator frequency monitoring. A watchdog timer is also included to monitor external MCUs.


Watchdog timer function block.

Watchdog timer function block. Image from Toshiba

The new TB8045FNG IC series features selectable operations for failure detections. Users can set their systems to respond to two different detected failures using the SPI communication input.

One way to do this is to use the setting that outputs a reset signal to the system; the other setting provides a notification of the failure. 


Notable Features Across the Four ICs

The new TB9045FNG series is outfitted with a built-in 6V buck DC-DC converter with a low-side operation voltage (down to 2.7V). Another buck DC-DC converter includes selectable output voltages for the four ICs:

Block diagram of TB9045FNG-120.

Block diagram of TB9045FNG-120. Image from Toshiba

The new series incorporates four power supply circuits (4 outputs) to receive the 6V input generated by the DC-DC converters.

They also include a circuit with a 5V (at 400mA) constant voltage for microcontrollers, along with three circuits with 5V (at 100mA) constant voltage for sensors.