CN204659637U - Based on the car load CAN wake-up circuit of TJA1041AT interface chip - Google Patents

Abstract

The utility model relates to a whole vehicle CAN wake-up circuit based on the TJA1041AT interface chip, including the TJA1041AT interface chip, the 12V level signal of the whole vehicle KL_30 is used as a trigger signal to connect to the V _BAT pin of the TJA1041AT interface chip, and the ignition signal KL_15 is used as a trigger signal to connect to the TJA1041AT The wakeup pin of the interface chip, the CAN bus provides a message as a trigger signal connected to the TJA1041AT interface chip and EN pin, the wake-up or standby signal output by the INH pin of the TJA1041AT interface chip, respectively connected to the wake-up terminal of the 12V power supply loop, the enable terminal of the 12V to 5V power supply chip and the 12V to 3.3V power supply chip. Through the reasonable configuration of the pin hardware circuit of the CAN transceiver chip, the CAN wake-up mode of the electric vehicle is more optimized, and finally the electric vehicles of different models and different working conditions can meet the ideal quiescent current requirements.

Description

Vehicle CAN wake-up circuit based on TJA1041AT interface chip

technical field

The utility model relates to the field of electricity, in particular to an automobile control circuit, in particular to a vehicle CAN wake-up circuit based on a TJA1041AT interface chip.

Background technique

In recent years, the new energy vehicle industry has attracted more and more attention, and the requirements for its vehicle controller system technology have become increasingly stringent. Among them, there are still many applications in new energy vehicle systems that require continuous power supply, even when parking. The most important requirement for these applications is low quiescent current. By optimizing the control circuit, selecting devices with lower power consumption, and matching the proper vehicle CAN sleep and wake-up functions, the purpose of reducing the quiescent current of the vehicle controller can be achieved.

Because many existing electric vehicles do not have the CAN sleep and wake-up function of the whole vehicle, the quiescent current of the whole vehicle is too large during the standby process, and the low-voltage battery consumes too much power, so that the energy of the battery cannot be used more effectively. At present, the CAN wake-up mechanism of some vehicle controllers cannot fully meet the working status requirements of various types of vehicles.

Contents of the invention

The utility model is aimed at the problem of vehicle control optimization, and proposes a vehicle CAN wake-up circuit based on the TJA1041AT interface chip, so that the electric vehicle controller enters the sleep mode when the vehicle does not work for a long time, and finally achieves vehicle control The quiescent current of the device in the shutdown state is reduced to a minimum requirement. And it can provide a variety of wake-up mode options when the vehicle is in different standby conditions, and comprehensively solve the vehicle CAN wake-up requirements of different models.

The technical scheme of the utility model is: a whole vehicle CAN wake-up circuit based on the TJA1041AT interface chip, including the TJA1041AT interface chip, the 12V level signal of the whole vehicle KL_30 as the trigger signal connected to the V _BAT pin of the TJA1041AT interface chip, and the ignition signal KL_15 as the The trigger signal is connected to the wakeup pin of the TJA1041AT interface chip, and the CAN bus provides messages as the trigger signal to the TJA1041AT interface chip. and EN pin, the wake-up or standby signal output by the INH pin of the TJA1041AT interface chip, respectively connected to the wake-up terminal of the 12V power supply loop, the enable terminal of the 12V to 5V power supply chip and the 12V to 3.3V power supply chip.

The 12V to 5V power supply chip and the 12V to 3.3V power supply chip are selected as TPS5410QDRQ1, and the INH pin output of the TJA1041AT interface chip is connected to the ENA pin of the enable terminal through a voltage dividing resistor.

Both the ignition signal KL_15 and the INH pin output of the TJA1041AT interface chip are connected to the wake-up terminal of the 12V power supply loop.

The beneficial effects of the utility model are: the utility model is based on the TJA1041AT interface chip CAN wake-up circuit of the vehicle, through the reasonable configuration of the hardware circuit of the CAN transceiver chip pins, combined with the action of the MCU on the I/O port, the CAN of the electric vehicle can The wake-up mode is more optimized, and finally electric vehicles of different models and working conditions can meet the ideal quiescent current requirements. It provides new technical means for research on improving the energy utilization efficiency of electric vehicles.

Description of drawings

Fig. 1 is the utility model CAN wake-up circuit diagram;

Fig. 2 is the working circuit diagram of the utility model power supply chip;

Fig. 3 is a circuit diagram of the 12V voltage circuit determined by the ignition signal KL_15 and the INH pin of the utility model.

Detailed ways

First, configure the TJA1041AT interface chip and EN pin level to control the wake-up mechanism of the CAN transceiver part, and use the adjustment of its V _BAT pin, wakeup pin and bus CAN messages to complete the control of its INH level conversion, and finally through the INH of the TJA1041AT chip The level conversion of the pin controls the enable end of the circuit power supply chip, and thus controls the standby and restart of the controller power supply circuit, and finally realizes the CAN wake-up mechanism of the vehicle controller.

As shown in Figure 1, the CAN wake-up circuit diagram, by configuring the INH pin of TJA1041AT as a high level, and triggering the enable terminal ENA pin of the power supply chip TPS5410QDRQ1 in Figure 2 (the fifth pin of INH1 ) is set to a high level, so that it can establish a power supply circuit of 5V and 3.3V within 10ms. This pin is connected to the anode of the D3 diode at the same time as the KL_15 vehicle ignition signal, providing two wake-up options for the establishment of the 12V voltage circuit, as shown in Figure 3. At the same time the MCU will and EN are configured as high level, and finally complete the process of waking up TJA1041AT.

By configuring the INH pin of TJA1041AT as low level, TJA1041AT enters the sleep state, and pulls the enable terminal ENA pin of the power supply chip TPS5410QDRQ1 in Figure 2 to low level through the flag bit of this pin, so that the power supply circuit Enter sleep mode, since the system stops power supply to MCU at this time, then and EN pins are pulled to low level by the hardware circuit at this time, as shown in Figure 1.

The working process of the utility model: the utility model provides three wake-up modes, which are determined by the way INH is configured as a high level.

Method 1: V _BAT is connected to the 12V level of the vehicle KL_30 to trigger the INH high level.

Method 2: The wakeup pin is provided with an external rising/falling edge. (When KL_15 is connected, it rises from 0 to 12V, and a rising edge is generated; when KL_15 is disconnected, it drops from 12 to 0V, and a falling edge is generated)

Method 3: The INH high level is triggered by a message provided by the CAN bus.

(V _CC and V _I/O are given 5V and 3.3V by the power chip enabled by INH pin control respectively.)

The CAN sleep and wake-up modes provided by the utility model under different working conditions of the electric vehicle are as follows:

(1) Put the vehicle in OFF gear, triggering the sleep mode of the vehicle controller.

When the vehicle is in the OFF gear, the ignition signal KL_15 is pulled low, and the high voltage power of the vehicle is cut off. The controller controls the CAN wake-up mechanism of the vehicle by collecting the KL_15 signal. When the controller detects that KL_15 is low, the MCU will and EN are configured as low level, INH level is pulled low, D3 connected to it and the enable terminal ENA of TPS5410QDRQ1 are pulled low, and the system power supply circuit enters sleep mode.

(2) Put the vehicle in the ON gear, and trigger the wake-up mode of the vehicle controller.

At this time, the whole vehicle has high-voltage power supply, and at the same time, the WAKEUP pin of the CAN chip receives a rising edge through the ignition signal, and the INH pin of the CAN chip gives a level pulse of about 12V for 8ms, and the connected D3 and The enable terminal ENA of TPS5410QDRQ1 has achieved the purpose of establishing the 12V, 5V, 3.3V power supply circuit within 10ms after the rising edge of the level pulse given by the INH pin, so as to keep the INH pin at high state. When 5V and 3.3V are established, the MCU is powered on and will and EN configured high, and set the TOD pin high. After the above whole process, the system wakes up and works.

(3) The whole vehicle is in OFF gear (the whole vehicle has no KL_15 signal), and the sleep mode of the vehicle controller is triggered.

This model has no KL_15 ignition signal, and the whole machine needs to control the CAN wake-up mechanism of the whole vehicle by collecting high-voltage signals. When the controller detects that the high-voltage bus is powered off, the MCU configures STB and EN to be low, and the INH level is pulled low. , the D3 connected to it and the enable terminal ENA of TPS5410QDRQ1 are pulled low, and the system power supply circuit enters sleep mode.

(4) The whole vehicle is in ON gear (the whole vehicle has no KL_15 signal), triggering the wake-up mode of the vehicle controller.

At this time, the whole vehicle has high-voltage power supply, and at the same time, the CAN chip controls the INH pin through the bus message to give a level pulse of about 12V for 8ms. Through this pulse, D3 connected to the enable terminal ENA of TPS5410QDRQ1 has reached the The 12V, 5V, 3.3V power supply circuit is established within 10ms after the rising edge of the level pulse given by the INH pin, so as to keep the INH pin at a high level. When 5V and 3.3V are established, the MCU is powered on and will and EN configured high, and set the TOD pin high. After the above whole process, the system wakes up and works.

Claims (3)

1. based on a car load CAN wake-up circuit for TJA1041AT interface chip, it is characterized in that, comprise TJA1041AT interface chip, the 12V level signal of car load KL_30 meets TJA1041AT interface chip V as energizing signal _bATpin, ignition signal KL_15 connects TJA1041AT interface chip wakeup pin as energizing signal, and CAN provides message to connect TJA1041AT interface chip as energizing signal with EN pin, what TJA1041AT interface chip INH pin exported wakes up or standby signal, connects that 12V electric power loop wakes end up, 12V turns 5V power supply chip and 12V turns 3.3V power supply chip Enable Pin respectively.

2. according to claim 1 based on the car load CAN wake-up circuit of TJA1041AT interface chip, it is characterized in that, described 12V turns 5V power supply chip and 12V and turns 3.3V power supply chip and select TPS5410QDRQ1, and TJA1041AT interface chip INH pin exports and connects Enable Pin ENA pin by divider resistance.

3. according to claim 1 based on the car load CAN wake-up circuit of TJA1041AT interface chip, it is characterized in that, described ignition signal KL_15 and the output of TJA1041AT interface chip INH pin all access 12V electric power loop and wake end up.