CS32L010 is a 32-bit MCU with low voltage reminder

Generally speaking, engineers with rich experience in iBOX (Internet of Vehicle Intelligent Terminal) product development may have been exposed to the problem that the KL30 (battery supply voltage) voltage is too low and causes the iBOX to shut down.

V2X: Intelligently connect the car to its surroundings and the cloud

When the MCU detects that the KL30 is below the operating voltage, it will issue an instruction to close the CAN communication interface, allowing the iBOX to take offline the vehicle CAN network. When the MCU detects that the KL30 is in the abnormal voltage range, due to the requirements of automotive safety and product protection, it will instruct the iBOX product to shut down or restart.

However, this may have been just a misunderstanding. The actual voltage of KL30 may not be lower than the rated working voltage, but due to the voltage sampling error of KL30, the MCU issues an incorrect command, which makes the iBOX and other car networking products enter a dormant or shutdown state, which seriously affects the user experience of the product.

iBOX system architecture

For example, when people forget to turn off the headlights, at this time, due to the huge energy consumption of external power consumption devices, the battery power is rapidly consumed, and the L30 voltage drops below the working voltage of the MCU, resulting in the MCU being unable to report data and turning off abnormally.

Similar scenarios are actually quite common in everyday automotive applications. When the iBOX product is in the process of hibernation, because some devices are not turned off or enter a low-power mode, it happens that the user hopes to wake up the iBOX through the mobile phone, but finds that the iBOX cannot be contacted.

Is there a way to avoid this poor experience? At this time, smart engineers will definitely think of the voltage detection of KL30, but at this time, the MCU is also in a dormant state and cannot be detected.

So, is there an MCU that can detect voltage even in a sleep state?

The CS32L010 accurately monitors the KL30 voltage threshold and wakes up the iBOX sleep mode in time

The CS32L010 chip, a 32-bit MCU, is built with a voltage comparator (COMP) with three configurable positive/negative external input channels and an internal BGR 2.5V reference voltage.

The COMP output can be used for timer TIM1, TIM10/TIM11, LPTimer, and programmable count array PWMC capture, gating, and external counting. Asynchronous interrupts can be generated based on rising/falling edges to wake up the MCU from low-power mode. And configurable software stabilization.

Just configure the voltage comparator, sleep mode can also monitor the KL30 voltage, when the KL30 is below the threshold, will wake up the iBOX through the MCU, notify the user through the iBOX that the battery is about to be exhausted, and then remind the user to pay attention to the car status in time, to avoid the car battery consumption is too low and the shutdown can not start the embarrassment.

In addition, the CS32L010 integrates a 12-bit high-precision, high-slew rate successive approximation (SAR) analog-to-digital converter (ADC) module inside the chip based on customer needs. Has the following product features:

◆ 12-bit conversion accuracy

◆ 1Msps conversion speed

◆ 8 conversion channels: 7 pin channels, 1 VCAP calibration channel

◆ Refence Voltage is the supply voltage

◆ ADC voltage input range: 0-VREF

◆ 3 conversion modes: single conversion, continuous conversion, cumulative conversion

◆ ADC's slew rate software can be matched

◆ Support on-chip and peripheral interrupts to automatically trigger ADC conversion startup, effectively reducing chip power consumption and improving conversion real-time

From the product features of the CS32L010, we can see that the product has 8 conversion channels: including 7 pin channels and 1 VCAP calibration channel. This is shown in the following figure.

ADC hardware design drawing

The CS32L010's ADC detection channel supports threshold detection, which removes sampling errors caused by abnormal voltage fluctuations.

Threshold detection design drawing

Moreover, the CS32L010 comes with a function of accumulating test results, which can easily obtain the average value of the test results, avoid the subtle errors caused by the detection voltage fluctuations, greatly reduce the workload of the developer, and ensure the accuracy and reliability of the test results.

At present, due to the impact of the global epidemic and the great power game, the large-scale shortage of the automotive industry, especially the vehicle-grade MCU chips, has led to a number of car companies to reduce orders and reduce production. As a leading enterprise in the field of domestic signal chain chips, Core Sea Technology is gradually entering the field of vehicle regulation MCU. The company's first automotive grade signal chain MCU passed the AEC-Q100 certification, has begun to be imported into the design of automotive front-loading products, and was selected into the 2021 automotive electronic chip innovation product list.

In the future, relying on the technology precipitation and first-mover advantage of high-precision low-power ADCs and high-reliable MCU chips, Core Pacific Technology will firmly grasp the industrial trend of "domestic substitution", continue to enter the field of automotive electronics, industrial applications and high-end consumer electronics, and strive to become the mainstay of national IC design manufacturers.