US-20260126480-A1 - ELECTRONIC CONTROL UNIT AND FAULT INFORMATION TRANSMISSION CIRCUIT

US20260126480A1US 20260126480 A1US20260126480 A1US 20260126480A1US-20260126480-A1

Abstract

The present application relates to an Electronic Control Unit (ECU), which includes a first chip and a second chip. The first chip comprises a first fault information transmission circuit, and the second chip comprises a second fault information transmission circuit. The first fault information transmission circuit comprises: a single fault pin, coupled to the fault pin of the second chip, configured to transmit and receive fault information; a current detection circuit, configured to detect whether current is present in the first fault information transmission circuit; a voltage regulation unit, configured to receive a voltage input from within the first chip and to output a fault voltage only when a fault is present in the voltage input; a back-to-back protection circuit, coupled between the single fault pin and the voltage regulation unit; and a fault monitoring circuit, configured to monitor the fault voltage output by the voltage regulation unit or the fault information received by the single fault pin from the second chip. The present application further relates to a fault information transmission circuit.

Inventors

Xiaofei Qiu
Ruediger Karner

Assignees

ROBERT BOSCH GMBH

Dates

Publication Date: 20260507
Application Date: 20250617
Priority Date: 20240621

Claims (10)

1 . An electronic control unit (ECU) comprising a first chip and a second chip, wherein the first chip includes a first fault information transmission circuit, and the second chip includes a second fault information transmission circuit, and wherein the first fault information transmission circuit comprises: a single fault pin, coupled to a fault pin of the second chip, configured to transmit and receive fault information; a current detection circuit, configured to detect whether a current is present in the first fault information transmission circuit; a voltage regulation unit, configured to receive a voltage input from within the first chip and to output a fault voltage only when a fault is present in the voltage input; a back-to-back protection circuit, coupled between the single fault pin and the voltage regulation unit, wherein the back-to-back protection circuit is configured to transmit the fault voltage output by the voltage regulation unit to the single fault pin when the current detection circuit detects the presence of current in the first fault information transmission circuit; and further configured to prevent the received fault information from being transmitted to the current detection circuit and the voltage regulation unit when the single fault pin receives fault information from the second chip; and a fault monitoring circuit, configured to monitor the fault voltage output by the voltage regulation unit or the fault information received by the single fault pin from the second chip.
2 . The ECU according to claim 1 , wherein the first chip and the second chip are application-specific integrated circuit chips.
3 . The ECU according to claim 1 , wherein the first fault information transmission circuit and the second fault information transmission circuit have the same circuit structure.
4 . The ECU according to claim 1 , wherein the fault monitoring circuit comprises: a first monitoring resistor; a second monitoring resistor; and a voltage monitoring node located between the first monitoring resistor and the second monitoring resistor, wherein the voltage at the voltage monitoring node is designed to indicate the type of fault that has occurred; wherein one end of the first monitoring resistor is coupled to the single fault pin and the back-to-back protection circuit, and the other end of the first monitoring resistor is coupled to one end of the second monitoring resistor, and the other end of the second monitoring resistor is grounded.
5 . The ECU according to claim 1 , wherein the current detection circuit is configured to detect current in the first fault information transmission circuit when a fault is present in the voltage input.
6 . The ECU according to claim 5 , wherein the voltage regulation unit includes a switching element, and wherein the switching element is configured to be coupled with the current detection circuit and to conduct only when a fault exists in the voltage input, thereby enabling the current detection circuit to detect current in the first fault information transmission circuit.
7 . The ECU according to claim 6 , wherein the switching element is a MOS transistor.
8 . The ECU according to claim 7 , wherein the voltage regulation unit further comprises: an operational amplifier and a grounding resistor, wherein the non-inverting input of the operational amplifier receives the voltage input, the inverting input of the operational amplifier is coupled to one end of the grounding resistor, and the other end of the grounding resistor is grounded; the output of the operational amplifier is coupled to the gate of the MOS transistor, the drain of the MOS transistor is coupled to the current detection circuit, the source of the MOS transistor is coupled to the one end of the grounding resistor, and the source of the MOS transistor is coupled to the single fault pin via the back-to-back protection circuit.
9 . The ECU according to claim 1 , wherein the ECU further comprises a third chip, the third chip including a third fault information transmission circuit, and the third fault information transmission circuit has the same circuit structure as the first and second fault information transmission circuits.
10 . A fault information transmission circuit, wherein the fault information transmission circuit is disposed within a first chip and comprises: a single fault pin, coupled to a fault pin of a second chip, configured to transmit and receive fault information; a current detection circuit, configured to detect whether current is present in the fault information transmission circuit; a voltage regulation unit, configured to receive a voltage input from within the first chip and to output a fault voltage only when a fault is present in the voltage input; a back-to-back protection circuit, coupled between the single fault pin and the voltage regulation unit, wherein the back-to-back protection circuit is configured to transmit the fault voltage output by the voltage regulation unit to the single fault pin when the current detection circuit detects the presence of current in the fault information transmission circuit; and further configured to prevent the received fault information from being transmitted to the current detection circuit and the voltage regulation unit when the single fault pin receives fault information from the second chip; and a fault monitoring circuit, configured to monitor the fault voltage output by the voltage regulation unit or the fault information received by the single fault pin from the second chip.

Description

TECHNICAL FIELD The present application relates to the field of fault information transmission, and more particularly, to an electronic control unit (ECU, Electronic Control Unit) and a fault information transmission circuit. BACKGROUND In an electronic control unit system (e.g., an airbag ECU), an application specific integrated circuit chip ASIC provides functions such as ignition loop drivers, PSI interfaces, and power supply. To support a greater number of such functions, multiple ASICs are sometimes employed within the ECU system. In the event of a fault, these faults may occur in any one of the ASICs and may also be transmitted to other ASICs. Therefore, it is necessary to share fault information among the different ASICs. SUMMARY OF THE INVENTION The inventors of this application recognize that there is a limit to the number of pins available on ASICs, making it not appropriate to use multiple pins to share fault information among different chips. Moreover, in the prior art, there is no technical solution that allows the identification of the fault source (i.e., which specific chip has encountered a fault) and/or the fault type using only a single fault pin across multiple chips. According to one aspect of the present application, an Electronic Control Unit (ECU) is provided. The ECU includes a first chip and a second chip. The first chip comprises a first fault information transmission circuit, and the second chip comprises a second fault information transmission circuit. The first fault information transmission circuit includes: a single fault pin, coupled to the fault pin of the second chip, configured to transmit and receive fault information; a current detection circuit, configured to detect whether current is present in the first fault information transmission circuit; a voltage regulation unit, configured to receive an internal voltage input of the first chip and to output a fault voltage only when a fault occurs in the voltage input; a back-to-back protection circuit, coupled between the single fault pin and the voltage regulation unit; the back-to-back protection circuit is configured to transmit the fault voltage output by the voltage regulation unit to the single fault pin when the current detection circuit detects the presence of current in the first fault information transmission circuit; and the back-to-back protection circuit is further configured to prevent the fault information received by the single fault pin from the second chip from being transmitted to the current detection circuit and the voltage regulation unit; and a fault monitoring circuit, configured to monitor the fault voltage output by the voltage regulation unit or the fault information received by the single fault pin from the second chip. In other words, the single fault pin in the first fault information transmission circuit is coupled to the fault pin in the second fault information transmission circuit, thereby enabling fault information to be transmitted among multiple chips. Moreover, in addition to the single fault pin, the first fault information transmission circuit further includes a current detection circuit, a voltage regulation unit, a back-to-back protection circuit, and a fault monitoring circuit. Through the coordinated interaction among these circuits/units, the determination of fault-related information is facilitated, such as identifying the fault source (i.e., whether the fault originates from the first chip or another chip) and the fault type, among others. As a supplement or alternative to the above solution, in the aforementioned ECU, the first chip and the second chip are application-specific integrated circuit chips. As a supplement or alternative to the above solution, in the aforementioned ECU, the first fault information transmission circuit and the second fault information transmission circuit have the same circuit structure. As a supplement or alternative to the above solution, in the aforementioned ECU, the fault monitoring circuit comprises: a first monitoring resistor; a second monitoring resistor; and a voltage monitoring node located between the first monitoring resistor and the second monitoring resistor; the voltage at the voltage monitoring node is capable of indicating the type of fault that has occurred; one end of the first monitoring resistor is coupled to the single fault pin and the back-to-back protection circuit; the other end of the first monitoring resistor is coupled to one end of the second monitoring resistor; and the other end of the second monitoring resistor is grounded. As a supplement or alternative to the above solution, in the aforementioned ECU, when a fault occurs in the voltage input, the current detection circuit is capable of detecting current within the first fault information transmission circuit. As a supplement or alternative to the above solution, in the aforementioned ECU, the voltage regulation unit includes a switching element. The switching element