Comprehensive Analysis of CRH2512F24R9E04Z 2512 24.9R 2W EVER OHMS High-Power Thick-Film Chip Resistor
The part numbering system of EVER OHMS follows a clear and structured logic. Each segment of CRH2512F24R9E04Z conveys specific technical information:
Comprehensive Analysis of CRH2512F24R9E04Z 2512 24.9R 2W EVER OHMS High-Power Thick-Film Chip Resistor
I. Model Number Decoding
The part numbering system of EVER OHMS follows a clear and structured logic. Each segment of CRH2512F24R9E04Z conveys specific technical information:
-
CRH: Series code for EVER OHMS high-power thick-film chip resistors. C denotes Chip, R denotes Resistor, and H denotes High Power.
-
2512: Package size code corresponding to metric 6432, with body dimensions of 6.4 mm × 3.2 mm. This mid-to-large surface-mount package provides adequate heat dissipation area for power handling.
-
F: Tolerance grade. Grade F corresponds to ±1% resistance tolerance, meeting the accuracy requirements of precision sampling and feedback circuits.
-
24R9: Resistance value marking, where R serves as the decimal point. 24R9 indicates 24.9 ohms. This value falls within the low-to-mid resistance range, suitable for current sensing and voltage divider applications.
-
E04: Temperature coefficient of resistance (TCR) code. E04 represents ±100 ppm/°C, meaning the resistance changes by no more than 100 parts per million per degree Celsius.
-
Z: Packaging code indicating tape-and-reel format. Standard packing is 4,000 pieces per reel, compatible with high-speed SMT placement equipment.
From the model number alone, one can quickly identify this component as a 2512 package, 24.9-ohm, ±1% tolerance, 2-watt rated, ±100 ppm/°C TCR high-power thick-film chip resistor.
II. Key Product Parameters
表格
| Parameter | Specification |
|---|---|
| Nominal Resistance | 24.9 Ω (24R9) |
| Resistance Tolerance | ±1% (Grade F) |
| Rated Power | 2 W (@ 70°C) |
| Temperature Coefficient (TCR) | ±100 ppm/°C |
| Operating Temperature Range | -55°C to +155°C |
| Maximum Working Voltage | 200 V |
| Overload Voltage | 400 V |
| Insulation Resistance | >10 GΩ |
| Thermal Resistance | 75°C/W |
| Package Dimensions | 6.4 mm × 3.2 mm × 0.55 mm |
| Packaging | 4,000 pcs per reel |
This resistor can continuously dissipate 2 W at an ambient temperature of 70°C. Beyond 70°C, power must be derated at 12.5 mW/°C. For example, at 100°C ambient, the recommended maximum power dissipation reduces to 1.625 W to ensure long-term reliability.
III. Product Applications
1. Power Management and Conversion Circuits
In AC-DC switching power supplies, DC-DC converters, and LED drivers, the 2512 24.9R 2W resistor is commonly used in secondary-side current sensing, voltage divider, and current-limiting circuits. The 2-watt power rating provides margin for continuous power dissipation, while the 24.9-ohm value enables accurate current detection when paired with operational amplifiers. In battery management systems (BMS), this resistor serves in cell balancing circuits, limiting equalization current to a safe range of 100–150 mA.
2. Industrial Control and Automation Equipment
In PLC modules, servo drives, inverters, and industrial sensors, the 24.9-ohm value is well-suited for constructing voltage divider networks that step down 24 V industrial signals to ADC-compatible levels such as 3.3 V. The ±1% accuracy ensures precise signal conditioning, and the -55°C to +155°C operating range accommodates extreme temperature fluctuations in industrial environments.
3. Automotive Electronics
In onboard chargers (OBC), LED headlamp drivers, BMS slave units, and body control modules, this resistor is used for PFC circuit current sensing, gate drive resistance, and high-voltage isolation divider networks. Its wide-temperature performance and anti-vibration structure meet the stringent reliability demands of automotive electronics.
4. Consumer Electronics and Communication Equipment
In high-power audio systems, smart home appliances, notebook power adapters, and 5G base station power modules, the 2512 package delivers 2-watt capability while maintaining a relatively compact footprint for high-density PCB layouts. In audio amplifier Zobel networks, the 24.9-ohm value effectively counteracts speaker voice-coil inductance and suppresses high-frequency oscillation.
IV. Technical Advantages
1. Enhanced Power Design Within Standard Footprint
Conventional 2512 thick-film resistors are typically rated at 1 W. The CRH2512F24R9E04Z achieves 2 W within the same package size through optimized resistor body geometry, improved electrode layout, and high-thermal-conductivity ceramic substrate. The power density reaches more than 1.5 times that of standard thick-film resistors, providing greater safety margin for medium-power circuit designs.
2. Thick-Film Process Ensuring Long-Term Stability
Using screen-printing technology, ruthenate-based resistive paste is applied onto a 96% alumina ceramic substrate and fired at high temperature to form a dense resistive film layer. Combined with a glass-encapsulated protective coating, this resistor passes 1,000-hour 85°C/85% RH humidity testing, 1,000-cycle -55°C to +155°C thermal shock testing, and 2.5× rated voltage short-term overload testing, exhibiting minimal resistance drift over extended operation.
3. Environmental Compliance and Process Compatibility
The terminal electrode employs a three-layer structure: silver-palladium inner layer, nickel barrier layer, and pure tin plating. This design is compatible with lead-free reflow soldering (peak 260°C) and wave soldering processes. The product complies with EU RoHS 2.0 directive and REACH regulations, containing no lead, mercury, cadmium, or other hazardous substances, satisfying global green manufacturing requirements.
| Model | Parameter |
| CRH2512F249RE04Z | 2512 249R 2W 1% |
| CRH2512F24K0E04Z | 2512 24K 2W 1% |
| CRH2512F24K3E04Z | 2512 24.3K 2W 1% |
| CRH2512F24R0E04Z | 2512 24R 2W 1% |
| CRH2512F24R9E04Z | 2512 24.9R 2W 1% |
| CRH2512F270RE04Z | 2512 270R 2W 1% |
| CRH2512F27K0E04Z | 2512 27K 2W 1% |
| CRH2512F27R0E04Z | 2512 27R 2W 1% |
| CRH2512F2K00E04Z | 2512 2K 2W 1% |
V. Brand and Supply Chain Strengths
EVER OHMS, founded in Taiwan, has focused on chip resistor research and manufacturing for over two decades. Its product portfolio covers thick-film resistors, thin-film resistors, metal alloy resistors, high-voltage resistors, and anti-sulfuration resistors. Production facilities are equipped with automated screen printing, laser trimming, and 100% inspection testing equipment, with monthly capacity reaching tens of billions of pieces. Products are widely used in power supplies, industrial control, automotive, and telecommunications applications worldwide.
For procurement, Shenzhen Shunhai Technology Co., Ltd. serves as a core authorized distributor of EVER OHMS resistors, maintaining ready stock of popular models including the CRH2512F24R9E04Z. The company offers rapid sample support and volume supply services with flexible lead times and responsive technical support. Another professional electronic component platform, HuaNian Mall (hnstshop.com), also provides online inquiry, datasheet download, and small-batch purchasing services for this model, with transparent pricing and real-time inventory updates, enabling engineers to quickly select and place orders.
VI. Selection and Usage Recommendations
-
Power Derating: Circuit actual power dissipation should not exceed 70% of the rated power, i.e., below 1.4 W, to avoid thermal aging from long-term full-load operation.
-
Thermal Design: It is recommended to allocate a copper foil heat dissipation area of no less than 100 mm² on the PCB and connect top and bottom layers with thermal vias, which can reduce thermal resistance by more than 40%.
-
Accuracy Matching: Current sensing and feedback loops must use ±1% (Grade F) models; general current-limiting and pull-up applications may use ±5% (Grade J) to reduce cost.
-
Alternative Models: Nearby values in the same series include CRH2512F24R0E04Z (24 Ω) and CRH2512F27R0E04Z (27 Ω). If tolerance requirements can be relaxed, CRH2512J24R9E04Z (±5%) is a lower-cost alternative.