CRCW251249R9FKE

High-power thick film resistors for surface mount applications

Manufacturer: ['dale', 'vishay', 'vishay-draloric']

series introduction

# Introduction to the CRCW251249R9FKE Product Series

## 1. Overview
The CRCW251249R9FKE belongs to a specific series of surface - mount resistors. These resistors are an essential component in a wide range of electronic circuits, providing precise resistance values to control current flow, divide voltages, and perform other crucial electrical functions.

## 2. Product Naming Convention
- **CRCW**: This is the general part number prefix for a particular resistor series from the manufacturer. It often indicates the resistor's construction type, package style, and some basic electrical characteristics associated with that series.
- **2512**: This refers to the physical size of the resistor in the surface - mount package. In the imperial measurement system, a 2512 package means the resistor has a length of 0.25 inches (6.35 mm) and a width of 0.12 inches (3.05 mm). This relatively large package size allows for better power dissipation compared to smaller packages.
- **49R9**: The resistance value of the resistor is 49.9 ohms. In resistor naming, the letter 'R' is used to represent the decimal point. So, '49R9' clearly indicates a resistance of 49.9 Ω.
- **F**: This represents the tolerance of the resistor. In the resistor tolerance code, 'F' stands for a tolerance of ±1%. This means that the actual resistance value of the CRCW251249R9FKE resistor can vary by up to 1% from the nominal value of 49.9 ohms. For example, the actual resistance could be anywhere between 49.401 ohms (49.9 - 0.499) and 50.399 ohms (49.9+ 0.499).
- **KE**: These are additional codes that may be used by the manufacturer to denote specific features, such as a particular manufacturing process, a special coating, or a specific application suitability.

## 3. Electrical Characteristics
### Resistance Value
As mentioned earlier, the nominal resistance value of the CRCW251249R9FKE is 49.9 ohms. This value is carefully controlled during the manufacturing process to ensure that it meets the specified tolerance. Precise resistance values are crucial in many applications, such as in precision measurement circuits, where even a small deviation in resistance can lead to significant errors in the measurement results.

### Tolerance
With a tolerance of ±1%, these resistors offer a high level of accuracy. This makes them suitable for applications where precise voltage division or current control is required. For example, in audio amplifier circuits, accurate resistor values are necessary to set the correct gain and bias levels, ensuring high - quality sound reproduction.

### Temperature Coefficient of Resistance (TCR)
The TCR of the CRCW251249R9FKE indicates how the resistance value changes with temperature. A low TCR is desirable as it means that the resistance remains relatively stable over a wide temperature range. This is important in applications where the operating temperature can vary significantly, such as in automotive electronics or industrial control systems.

### Power Rating
Due to its 2512 package size, the CRCW251249R9FKE typically has a relatively high power rating compared to smaller - sized resistors. This allows it to handle larger amounts of power without overheating. The power rating determines the maximum amount of power that the resistor can dissipate safely. For example, if the power dissipated in the resistor exceeds its rated power, it can lead to a significant increase in temperature, which may cause the resistor to fail

Images for reference

CRCW-2512

CRCW-2512

SMD Thick Film Side

SMD Thick Film Side

SMD Thick Film Top

SMD Thick Film Top

Datasheets

Partlist

CRCW251249R9FKEG
CRCW251249R9FKEGHP
CRCW251249R9FKEH