In today's rapidly expanding world of Internet of Things (IoT) devices, from smart sensors and wearable devices to industrial remote monitoring nodes, the key to long-term stable operation is often not processor performance, but—power management.
More specifically, it's the DC-DC converter that accurately converts the battery voltage to the voltage required by the MCU, wireless module, and sensors.
If your IoT device needs to operate on battery power for months or even years, then conversion efficiency is not just a "nice-to-have," but a matter of "life and death." This article will explain why high-efficiency DC-DC converters are so important and provide practical selection guidelines.
1. Power Supply Challenges for IoT Devices
Most IoT end devices have the following characteristics:
Battery-powered devices (using coin cells, lithium-ion batteries, AA batteries, etc.) installed in hard-to-reach locations (inside walls, underground pipes, mobile devices, etc.) require unattended operation for 1 to 10 years.
In such cases, even a current value of 1 microampere is extremely important. Even if the main control chip is in sleep mode 99% of the time, an inefficient power solution will drain the battery within a few weeks.
The Hidden Power Killer: Quiescent Current (Iq)
Many engineers tend to focus only on efficiency at full load and ignore quiescent current (the power consumed by the DC-DC converter itself when idle).
In ultra-low power IoT applications, low quiescent current is just as important as high efficiency.
2. Why are DC-DC converters better than low pressure rectifiers (LDOs)?
You can choose a simple low-voltage rectifier (LDO), because it is cheap and easy to design. However, LDO will convert a large amount of voltage into heat, causing its efficiency to be very low, especially when the input and output voltage difference is large (for example, 3.7V → 1.8V).
3. How to choose the best DC-DC converter for IoT devices: Below are some options.
Very low static current (Iq)
Lower than 10µA, preferably lower than 1µA (requires cooling support)
Maintain good performance across all load ranges
It ensures the best performance in the range of 10µA to 100mA, not just the best performance.
Note: It is recommended to use CSP packaging or integrated electrical module (such as µModule) to save PCB space
High input voltage model
Support multiple battery types (for example, Li-SOCl₂: 3.6V, lithium ion battery: 2.7-4.2V)
Fast short response time
secure the MCU Will not be exposed to wireless modules (eg, NB-IoT, LoRa) in reverse power supply mode
Reliability and authentication
For commercial/industrial applications, this product requires AEC-Q100 certification and complies with RoHS standards.
Using a standard LDO (Iq=50 µA, 50% efficiency) → Battery depleted within 1 year
Switching to a high-efficiency DC-DC (Iq=0.8 µA, average efficiency 85%) → Easily achieves 5+ years of operation
This is the power of choosing the right power supply.
In the world of IoT, energy is the most scarce resource. High-efficiency DC-DC converters are not just power devices, but the cornerstone of device longevity, reliability, and user experience.
By prioritizing ultra-low quiescent current, high efficiency across a wide load range, and high integration, you can upgrade a "barely usable" design into a truly competitive IoT product.
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