Disassembly: How Car Keys Achieve Low Power Consumption?

Introduction

Car remote keys use practical button batteries, which can generally operate for a long time, so their power consumption is very low. How do they achieve low power consumption? Let’s disassemble a Buick Excelle to take a look.

Disassembly

Use a flathead screwdriver to pry open the battery cover.

Disassembly: How Car Keys Achieve Low Power Consumption?

Disassembly: How Car Keys Achieve Low Power Consumption?

Disassembly: How Car Keys Achieve Low Power Consumption?

Unscrew two screws.

Disassembly: How Car Keys Achieve Low Power Consumption?

Then find that it still won’t open. Don’t worry, there is still a hidden screw under the logo.

Disassembly: How Car Keys Achieve Low Power Consumption?

Disassembly: How Car Keys Achieve Low Power Consumption?

Unscrewing this screw will pop it open, and you can see the lock’s spring mechanism.

Disassembly: How Car Keys Achieve Low Power Consumption?

Let’s focus on the PCB.

Disassembly: How Car Keys Achieve Low Power Consumption?

This side has the MCU and battery holder, next to it is a 32k crystal used for the RTC clock during sleep. There is a filter capacitor nearby.

Disassembly: How Car Keys Achieve Low Power Consumption?

The MCU model is TMS37F158LG-84TG.

Disassembly: How Car Keys Achieve Low Power Consumption?

Disassembly: How Car Keys Achieve Low Power Consumption?

Onboard antenna.

Disassembly: How Car Keys Achieve Low Power Consumption?

Crystal oscillator T130, temperature-compensated crystal oscillator, likely used for RF.

Disassembly: How Car Keys Achieve Low Power Consumption?

Button.

Disassembly: How Car Keys Achieve Low Power Consumption?

749CXAS should be the RF chip.

Disassembly: How Car Keys Achieve Low Power Consumption?

Disassembly: How Car Keys Achieve Low Power Consumption?

Conclusion

1. Uses dedicated low-power chips, with low operating frequency and low power consumption.

2. Simple peripheral circuits, entering sleep mode when not in use, avoiding unnecessary current consumption from pull-up and pull-down resistors.

END

Related posts

  1. Detailed Use of Android Bluetooth Basic Framework
  2. Analysis Report on 35 Domestic Power Management Chip Manufacturers
  3. Understanding China Unicom’s NB-IoT: Wide Coverage, Low Power Consumption, Massive Connectivity, and Low Cost
  4. Installing Smart Smoke Detectors Increases Escape Chances by 50%!
  5. Introducing TI’s Speech Recognition Library Based on Cortex-M4 with API and User Manuals
  6. Low Power Design Strategies – Resource Sharing
  7. Understanding Block Ciphers: A Comprehensive Overview
  8. Principles and Interface Technologies of Microcomputers
  9. Comprehensive Guide to Installing Android Studio
  10. Arduino Launches ESP32S3 Development Board: The Arduino Nano ESP32
  11. Application of MCC Data Acquisition Card Based on Raspberry Pi
  12. Performance Testing of Raspberry Pi 4 Using RT-Thread
  13. Experience Running RT-Smart on Raspberry Pi 4
  14. 32-bit ARM Cortex-M0+ Microcontroller – PY32C642
  15. 7 IoT Devices That Worry Security Experts
  16. One ARM Server, ‘A Cloud’: ZStack Truly Achieved It
  17. Detailed Explanation of ARM Compilers (armcc/armclang)
  18. Improved Lithium-Ion Battery SOC Prediction Method with High Accuracy and Fast Computation
  19. Trends in Smart Cockpit Domain Controller Technology Development

Leave a Comment