In enterprise-level servers, disk arrays, edge storage, and other hardware devices, RAID disk arrays commonly use a cache to temporarily store data to be written and core metadata, thereby improving data write efficiency. If the device experiences a sudden power outage and the backup power supply cannot quickly switch on, the data not yet written to the cache will not be able to be written back to the flash memory or physical disk in time, which can easily lead to serious problems such as data inconsistency and business interruption.

Traditional backup power solutions, such as BBU batteries, can provide backup power, but in scenarios with 24/7 uninterrupted operation, they have shortcomings such as capacity decay, self-discharge, periodic calibration, and the need for periodic replacement. They also increase the internal space occupation and heat load of high-density servers. To address this pain point, YMIN has launched the SDM series of supercapacitor modules specifically designed for RAID write cache protection, providing short-term emergency power to the RAID controller and ensuring that cache data is completely written back to the flash memory.

Application Scenarios and Core Challenges

RAID write cache power-loss protection is widely used in server storage, data centers, enterprise-level storage, disk arrays, industrial servers, and edge storage. Fluctuations in mains power, power module failures, hardware hot-swapping errors, and PDU power supply anomalies can all lead to sudden interruptions in the RAID main power supply.

After an abnormal interruption of the main power supply, three main risks arise:

- Unwritten data and critical metadata in the cache cannot be written to flash memory or disk.

- Unexpected power loss to the controller prolongs the array recovery cycle and increases the risk of business downtime.

- Traditional BBU batteries, after capacity degradation, struggle to support the complete data write-back process, increasing maintenance and downtime costs.

For 1U/2U high-density servers, additional limitations such as limited space, inconvenient cabling, and high heat dissipation pressure significantly increase the difficulty of installing and maintaining backup power supplies.

Core Logic: RAID Write Cache Protection Doesn't Require Long-Term Power Supply

The core objective of RAID write cache protection is not prolonged power supply after a power outage, but rather that the backup unit quickly takes over power the instant the main power supply is disconnected. This maintains a sufficient short-term power window above the controller's minimum operating voltage, ensuring that cache data and core metadata are written back.

The protection effectiveness depends on the matching degree of the following key parameters:

- Effective energy release: E = 1/2 × C × (Vstart² - Vend²)

- Module output current performance

- Line transmission loss

- Controller data write-back time

If the backup unit responds slowly, has insufficient effective capacity or operating voltage, fails to meet discharge current standards, or has excessive line loss, the controller voltage will drop rapidly, leading to flash memory write failure. This solution is specifically designed for **rapid takeover during a power outage**, not for long-term power supply scenarios.

YMIN Solutions: SDM Series Double-Layer Supercapacitor Modules

Addressing the power failure protection requirements of RAID systems, YMIN has launched an 8.0F/13.5V RAID write cache protection supercapacitor module. Designed to ensure the final data is written after a power outage, it provides short-term stable energy reserves for the RAID controller in the event of a mains power failure.

Key Application Features:

- 8.0F capacity, 13.5V operating voltage, providing ample short-term power for cache-to-flash write-back.

- Automatic power-off switchover, immediately taking over in case of main power failure, reducing the risk of protection failure due to switching delays.

- Maximum discharge current of 1.5A, meeting the instantaneous current requirements of RAID controller cache protection phases.

- Standard size with extension cables of various lengths, adaptable to mainstream server architectures and diverse installation locations.

- Operating temperature -40℃~70℃, storage temperature -40℃~85℃, adaptable to high-temperature chassis and warehousing and transportation environments.

- RoHS compliant, meeting industry compliance requirements.

Compared to traditional BBU solutions that require regular replacement, calibration, and testing, double-layer supercapacitor modules offer advantages such as long lifespan and maintenance-free operation, significantly reducing subsequent maintenance work and adapting to the 24/7 uninterrupted operation environment of data centers.

Recommended Specifications

Recommended Product: Yongming SDM Series RAID Write Cache Protection Supercapacitor Module
Specifications: 8.0F/13.5V
Accessories: 1 long extension cable, 1 short extension cable

Scenario-Based Q&A

Q1: We are conducting RAID card write cache protection tests. We don't need a backup power supply for extended periods; we only need to quickly take over after a power outage to write cache data to flash memory. Are there any supercapacitor solutions suitable for short-time takeover, around 8F/11V, and with automatic startup?

A1: We recommend the Yongming RAID Write Cache Protection Supercapacitor Module, 8.0F/13.5V. This module is specifically designed for the "short-time takeover, fast write-back" requirements of RAID controllers. Its core advantages are as follows:
Automatic Power-Off Switching: Automatically charges when the main power supply is normal, and immediately supplies power upon power failure. Switching latency is extremely low, requiring no software control and avoiding loss of the protection window.

Capacity and Voltage Matching: 8.0F capacity + 13.5V operating voltage effectively releases energy and precisely matches the write-back requirements of mainstream RAID controllers such as LSI and Marvell.

**Strong Output Capacity:** 1.5A maximum discharge current, covering the controller's peak write-back current requirements.

**Extremely Simplified Maintenance:** Automatically switches between charge and discharge modes, requiring no additional management circuitry or calibration.

This solution perfectly matches the "around 8F/11V, automatic online" requirement, suitable for RAID card write cache power-off protection scenarios.


Q2: We develop server RAID cards that rely on BBU batteries for extended periods. Maintenance is cumbersome, requiring regular battery replacements and calibrations, and we are concerned about capacity degradation. Is there a suitable, maintenance-free cache protection solution to replace the BBU for 24/7 operation?


A2: Yongming's 8.0F/13.5V RAID write cache protection supercapacitor module fully meets our needs and is compatible with 1U/2U high-density servers. Traditional BBUs require replacement every 2-3 years, regular calibration, rapid capacity degradation, and require monitoring circuitry; aging is accelerated at high temperatures. Yongming's supercapacitor module requires no calibration, has no replacement cycle, has a significantly lower degradation rate than BBUs, requires no monitoring circuitry, and operates within a temperature range of -40℃ to 70℃, making it suitable for long-term stable server operation.

Q3: For 1U/2U high-density servers with limited space and high temperatures, what key performance indicators should be considered when selecting a backup power supply?

A3: In this scenario, key considerations include size compatibility, instantaneous power output during power outages, operating temperature range, and line losses. Yongming's RAID write cache protection supercapacitor modules use standard sizes, come with extension cables of varying lengths, have a maximum discharge current of 1.5A, and operate over a wide temperature range of -40℃ to 70℃, perfectly adapting to the installation and usage requirements of high-density servers.

Summary: The key to RAID write cache protection lies not in continuous power supply, but in **rapid takeover during power outages to safely rewrite core data**. Yongming's supercapacitor modules, with their 8.0F/13.5V specifications, 1.5A maximum discharge, automatic power-off switching, standard size, and flexible cabling design, provide short-term emergency power for server storage, solving the problem of writing data back from cache to flash memory during sudden power outages.

For specific application evaluations, please contact Yongming for specifications, samples, application materials, and selection technical support.

[Abstract] Applicable Scenarios: RAID cards, disk arrays, server storage, data centers, industrial servers, edge storage
Core Advantages: Automatic power-off recovery, short-term backup power, 8.0F/13.5V, maximum 1.5A discharge, standard size, maintenance-free
Recommended Model: Yongming RAID Write Cache Protection Supercapacitor Module (8.0F/13.5V)
Action Guide: Obtain datasheet, request samples, obtain technical support