TU-TESL

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Toshiba today announced the launch of tb9044fng, a general system power IC for automotive applications, which has multiple outputs to achieve functional safety [1]. The delivery of samples will be started on this day, and the mass production plan will start in October 2017. More and more safety critical vehicle systems such as electric power steering system (EPS) and brake must meet the requirements of asil-d [2], which is the highest level of vehicle safety integrity specified in ISO 26262 functional safety standard. The new IC integrates multiple fault detection functions, such as high and low voltage detection of power circuit and overheat detection, to monitor the IC's own fault. In addition, a watchdog timer is also integrated to monitor the fault detection of external microcomputer. The IC also integrates the preliminary diagnosis circuit used to detect the latent fault in the fault detection circuit to ensure higher functional safety. Toshiba has also conducted a series of functional safety analysis to simulate various system faults, and will also provide customers with record documents such as functional safety fmeda [3] to support the overall safety analysis and design. Various built-in monitoring circuits for functional safety power supply low voltage detection circuit DC-DC converter (6V) high voltage detection circuit series power supply (5V) high voltage / low voltage detection circuit overheat detection circuit oscillator frequency monitoring circuit watchdog timer circuit of external micro controller (MCU) for functional safety fault detection circuit diagnosis circuit fault detection power A built-in diagnostic circuit is set in the circuit to detect any latent fault. The IC generates 6V output from the high efficiency DC-DC converter. Considering the voltage drop caused by the reduction of no-load voltage, the range of low side working voltage is improved to 2.7V (minimum). Built in 4 series power supply [4] circuits (4 outputs) the IC contains 4 series power supply circuits for receiving 6V input generated by DC-DC converter. The IC also includes a circuit with a constant voltage of 5V (current capacity of 400mA) for microcomputers and three circuits with a constant voltage output of 5V (current capacity of 100mA) for sensors and other interfaces. Each circuit can output a voltage independently. The optional operation user of fault detection can use SPI [5] communication input setting to set the system to respond to the detected fault in one of two ways. One setting outputs reset signal to the system; the other provides abnormal operation notice to the system. It can be selected according to the user's application or system. Note 1: Based on the standard of functional safety, in order to minimize the risk of system failure. Iso26262 certification confirms that the process or product of a company's electrical and electronic (E / E) system for automotive applications meets the strict standards specified in this standard, and provides an independent means for the third party to evaluate the capabilities of potential suppliers. Note 2: ASIL: vehicle safety integrity level note 3: fmeda: failure mode effects and diagnostic analysis note 4: series power supply: DC power circuit, where the voltage control elements are connected in series with the load. Note 5 SPI: serial peripheral interface