ABLIC launches the S-19721 series of automotive voltage trackers

Technological innovation in the automobile industry is progressing at a brisk pace in the fields referred to as CASE (Connected, Autonomous, Shared & Services and Electric). Especially, vehicles with the CASE capability of ‘autonomous driving’ have been provided with a wide variety of sensors to ensure operation of their Advanced Driver Assistance System (ADAS) and Autonomous Driving (AD) System to accurately assess the constantly changing conditions inside and outside the vehicle.

Many sensors provide an output that is proportional to the power supply voltage (ratiometric output). However, an Analog-to-Digital Converter (ADC), the measurement unit, in an ECU (Electronic Control Unit) requires that the power supply voltage of the sensor and the ADC have the same voltage to read values correctly. Due to space constraints, the ECU is often located away from the sensor and is connected to it by means of a wire harness. Also, the sensor power supply IC is located away from the MCU power supply IC to prevent damage to ECU internal components, such as ADC and MCU in the unlikely event of a wire harness failure. Since the sensor and MCU in the ADC use separate power supply ICs, their output voltages may become different (offset) and as such offset may lower reading accuracy, there is a risk that this may compromise vehicle safety, environmental performance, and ride quality.

The S-19721 Series of voltage trackers launched is in a class of ICs with the lowest offset voltage in the industry (*1) and provides accurate sensor readings in supplying ECU external sensors and components with electricity. This series can output up to 250mA and can cope with the high current output required by high performance sensors or power groups of sensor as the number of sensors multiplies.

What’s more, an anomaly notification function that detects IC anomaly and makes them known via the INT pin and other protective circuits protect ECUs even in the event of a wire harness failure to further improve safety.

The new S-19721 Series is in a class of ICs with the lowest offset voltage in the industry and comes with an anomaly notification function that makes known IC status. Combined with a number of protective circuits, it is a product that brings additional safety to autonomous driving. We provide versatile packaging that meets a variety of customer needs.

The-S-19721 Series is also PPAP (Production Part Approval Process) capable and planned for compliance with Grade 1 of the AEC (*)-Q100 (*Automotive Electronics Council) quality standard for automotive ICs.

1. Belongs to a class of sensors with the industry’s lowest offset voltage

The S-19721 Series of voltage tracker ICs has achieved an offset voltage as low as ±4.5mV. A low voltage tracking tolerance improves sensor reading accuracy.

2. Detecting and notifying the outside world of IC anomaly

The S-19721 Series integrates anomaly notification that detects IC anomaly and outputs them to the INT pin. This function copes with the three issues of output pin overvoltage and overcurrent, as well as IC thermal shutdown. It allows the user to select the combination of outputs through the INT pin that suit operating conditions and the application.

3. Versatile packaging

The S-19721 Series of voltage trackers offers 36V operation, 250mA output and can be placed in a standard HSOP-8A package, a high-heat dissipating TO-252-9S package or a compact HSNT-8(2030) package. Customers can select the package that best suits their application.

4. Integrates a variety of protection functions

The S-19721 Series integrates an overcurrent protection circuit, a thermal shutdown circuit in addition to a reverse current protection function. By limiting reverse current from the VOUT pin to the VIN pin to -5μA min., it protects devices from damage from short to supply and short to ground faults.

5. 36V input/45V rating

S-19721 Series is a high-withstand voltage product with an input voltage of 36V and a rating of 45V that can be directly connected to a 12V lead-acid battery.

(*1) When operating as a 36V, 250mA output automotive voltage tracker. Based on ABLIC research, as of July 2023

(*2) Take care to ensure that IC loss does not exceed the allowable power dissipation during high current output.

Application examples

• Power supplies for powering off-board sensors of automotive applications:

Current sensor, Temperature sensor, Torque sensor, Steering angle sensor, Ambient light sensor, Fuel sender gauge, etc.

• Automotive applications such as engines, transmissions, suspensions, ABS, EVs/HEVs/PHEVs:

Inverter, On Board Charger, BMS, EPS, ESC, Body Control Module, etc.