Shanghai electronic product development and design of low-cost

The most recent issue facing the design of wearable products is low-power design. After careful analysis of these two days concluded that the design of low-power methods to summarize, to 饗 users.

First of all, to understand that power consumption is divided into work-time power consumption and standby power consumption, work is divided into all functions of power-on and power-on of some functions. This largely affects the power consumption of the product design.

For an electronic product, the total power dissipation is the product of voltage and current for the normal operation of the product, which is one of the considerations for low-power design.

In order to reduce the power consumption of the products, try to adopt the product of low voltage and low power while developing the electronic product. For example, a product that used to work with a 5v microcontroller, then a 3.3v microcontroller or a lower operating voltage, then it is in the first level for a low-power design, which is what we often say low pre-research Device selection. This generally requires a wide range of chip coverage or with suppliers have good communication.

Followed by the choice of module control work, the general choice of sleep function chip. For example, in the design of a system, if some external modules are infrequently used in the work, we can put them into hibernation mode or use the digital switch in the hardware circuit design to control the work of the controller. When the module needs to be used It wakes up so that we can turn off some unnecessary devices as the system goes into low-power mode, saving power and prolonging standby time. Commonly used methods: ① has a sleep mode function chip ② MOS tube electronic switch ③ LDO chip with enable end.

Again, select the master chip with power-saving mode. Now the main control chip generally has a power-saving mode, the past experience can know that when the main control chip in power-saving mode, the operating current is often a fraction of the normal operating current, which can greatly enhance the consumer Product battery usage time. At the same time, some control chips now have a dual clock mode, and the configuration of the software enables the chip to use different externalities in different occasions to reduce its power consumption. This is always the same divider with the same purpose, the difference is presumably the price of the BOM. Now hot APPLE WATCH is an example of low power consumption: full-function run 3-4 hours, sustained operation 18 hours.

The main chip or related module wake-up options. Usually entered the above steps to design a good hardware structure, the Shanghai electronic product development in the system need to save power, when to enter the power-saving mode, which is generally achieved in the software design, but mainly depends on the product's functional characteristics to decide . When the system enters the power-saving mode, the wake-up of the system also needs control. General system wake-up is divided into automatic wake-up and external wake-up.

A, automatic wake-up is the use of internal timer chip to sleep time, when the sleep time reaches a predetermined time, automatically wake up. This is similar to the watchdog or interrupt we use, and the difference is the timing of its operation or not.

B, the external wake-up is the chip has been in a dormant state, when there is an external event (mainly through the interface) to trigger the chip, the chip will wake up, in the event of treatment to eliminate the trigger event and then go to sleep . Therefore, depending on the characteristics of the system, you need to design software to determine how to use sleep and wake-up to reduce system power consumption.

Finally, talk about power consumption test, power consumption test is divided into module power consumption and machine power consumption, the module power consumption need to test the power consumption and working hours dormancy power consumption. Machine power consumption is divided into the maximum load power consumption and basic functions of power consumption and dormancy power consumption. In the previous tests I used to directly measure the UI, on how to measure high-precision low-power products, described in the next article.