Advantages of High-Withstand Voltage Battery Monitoring ICs:-small footprint, reduced standby current, and higher accuracy-

Contents

Requirements for Automotive Voltage Monitoring
Conventional Power Supply Voltage Monitoring
Advantages of High-Withstand Voltage Battery Monitoring ICs
Introducing ABLIC’s High-Withstand Voltage Battery Monitoring ICs

　　-The S-19110 Series allows you to set an arbitrary threshold voltage!
　　-The S-191L/N Series comes with a supply voltage divided output

For application details, see “What is a Reset IC?”

For a detailed description, see “What is Functional Safety?”

1. Requirements for Automotive Voltage Monitoring

The appearance of Advanced Driver Assistance Systems or autonomous driving systems has increased the need for automotive safety.
Autonomous vehicles, especially, must continue functioning or bring the vehicle to a safe standstill in the event of an accident. This starts with detecting the occurrence of a failure.

The following are some of the safety mechanisms that can be used to detect failures in electric circuits.
　-Voltage monitoring
　-Current monitoring
　-Connection monitoring, etc.

In the next section, we will describe voltage monitoring used as a safety mechanism.

2. Conventional Power Supply Voltage Monitoring

The diagram at right is a block diagram of an automotive ECU. The following locations can be used for voltage monitoring.

-Monitoring voltage entering the ECU
Monitoring using a low-voltage voltage monitoring IC
Monitoring using the microcontroller AD converter with dividing resistors
-Monitoring LDO regulator or DC-DC converter output voltage
Monitoring using a low-voltage voltage monitoring IC

Monitoring both the above voltages, or mainly voltage drops, used to be the main trend. However, recent safety improvements have made it necessary to monitor voltage rises, as well.

The conventional method for monitoring voltage entering an ECU has multiple issues.
　-The great number of external parts involved increases board size
　-The current flowing through the dividing resistors increases standby current
　-The manufacturing variations in external parts adversely affect monitoring accuracy

The high-withstand voltage battery monitoring IC solves these issues.

3. Advantages of High-Withstand Voltage Battery Monitoring ICs

An advantage of a high-withstand voltage battery monitoring IC is that it eliminates the need for dividing resistors. This advantage solves both the increase in standby current and board size issues.
ABLIC’s high-withstand voltage battery monitoring ICs also provide additional advantages.

4. Introducing ABLIC’s High-Withstand Voltage Battery Monitoring ICs

The S-19110 Series allows you to set an arbitrary threshold voltage!

The following is an introduction to the S-19110 series, ABLIC’s battery monitoring IC.
The most important feature of the S-19110 series is that both the “detection voltage” and the “release voltage” can be set independently. This capability enables the user to configure the optimal voltage monitoring IC for their system.
Also, Voltage input pin (VDD) and the GND pin (VSS) have been placed away from each other to prevent inter-pin short-circuits and improve safety. Since also Detection voltage input (SENSE) pin is a high-withstand voltage pin, it can be directly connected to a 12V battery line without dividing resistors.

The S-191L/N Series comes with a supply voltage divided output

Next, we will introduce the S-191L/N series, ABLIC’s series of battery monitoring ICs.

The S-191L/N series integrates supply voltage divided output for greater safety.
Supply voltage divided output is a function that helps monitoring the microcontroller AD converter. Specifically, the dividing resistors for high-voltage monitoring, so far an external part, and the switch for lowering current consumption have been integrated into the IC. This new approach has rendered external parts unnecessary and enables the generation of voltage that can be input to the microcontroller AD converter.

Another feature is that negative voltage can be applied to Detection voltage input (SENSE) pin. A reverse connection protection diode is connected between Detection voltage input (SENSE) pin and the VSS pin. This means Detection voltage input (SENSE) pin can be connected before the reverse current protection diode even in systems that require a negative voltage application test. In this location, the pin is able to cancel out the lowering of monitoring accuracy caused by manufacturing variations in the reverse current protection diode.

Use the link below to learn more about the S-191L/N product.

Supply voltage divided output + overvoltage and undervoltage monitoring：S-191L/N Series