Vishay Dale WFM Power Metal Plate Current Sense Resistors
Vishay WFM Series Power Metal Plate Current Sense Resistors provide low-value sensing from 10mΩ to 500mΩ in 2010 and 2512 case sizes. These resistors use solid metal manganese-copper or nickel-chromium-aluminum alloy elements to deliver low TCR performance, very low inductance from 0.5nH to 5nH, and thermal EMF below 3μV/°C. They support an operating temperature range from –65°C to +170°C and are AEC-Q200 qualified. Typical applications include switching and linear power supplies, power amplifiers, battery management systems, power inverters, and instrumentation.
Features
- 2010 and 2512 size package
- AEC-Q200 qualified (1)
- Low thermal EMF (< 3 μV/°C)
- Proprietary processing technique produces low resistance values (10 m to 500 m)
- Solid metal manganese-copper and nickel chromium-aluminum alloy resistive element with low TCR (< 20 ppm/°C)
- Very low inductance 0.5 nH to 5 nH
Applications
- Battery Management
- Instruments
- Power Amplifiers
- Power Inverters
- Shunts
- Switching and Linear Power Supplies
Technical Specifications
| Parameter | Unit | Model | Resistor Characteristics | |
|---|---|---|---|---|
| 2010 | 2512 | |||
| Temperature coefficient (20 °C to 60 °C) (element only) (1) |
ppm/°C | All | < 20 | |
| Operating temperature range | °C | All | -65 to +170 | |
| Maximum working voltage (3) | V | All | (P x R)1/2 | |
| Maximum terminal temperature | °C | All | 110 | 95 |
| Temperature coefficient (-55 °C to +150 °C) (including terminals) (2) |
ppm/°C | WFMA | ± 110 | ± 110 |
| WFMB | ± 50 | ± 50 | ||
| Temperature coefficient (20 °C to 60 °C) (including terminals) (2) |
ppm/°C | WFMA | ± 30 | ± 40 |
| WFMB | ± 20 | ± 20 | ||
Dimensions and Construction Outline
Standard Electrical Specifications
| Part Number | Size | Power Rating/Terminal Temperature W |
Tolerance % |
Resistance Value Range Ω |
Weight (Typical) g/1000 Pieces |
|---|---|---|---|---|---|
| WFMA2010 | 2010 | 3.0 at 70ºC | ±1.0 | 0.010 to 0.0329 | 32 |
| WFMA2010 | 2010 | 2.0 at 110ºC | ±1.0 | 0.010 to 0.0329 | 32 |
| WFMB2010 | 2010 | 3.0 at 70ºC | ±1.0 | 0.033 to 0.500 | 32 |
| WFMB2010 | 2010 | 2.0 at 110ºC | ±1.0 | 0.033 to 0.500 | 32 |
| WFMA2512 | 2512 | 4.0 at 70ºC | ±1.0 | 0.010 to 0.0329 | 41 |
| WFMA2512 | 2512 | 3.0 at 95ºC | ±1.0 | 0.010 to 0.0329 | 41 |
| WFMB2512 | 2512 | 4.0 at 70ºC | ±1.0 | 0.033 to 0.500 | 41 |
| WFMB2512 | 2512 | 3.0 at 95ºC | ±1.0 | 0.033 to 0.500 | 41 |
Categories in This Series
Video
This TTI Tech Specs video for Vishay WFM Power Metal Plate Current Sense Resistors explains they are available in 2010 and 2512 case sizes, with power ratings up to 4 watts and resistance values from 10 to 500 milli-ohms.
See video transcript below
Video Transcript
I’ve recently started calling my cousin WFM. She’s a wishful 5 feet 2 inches tall (pretty sure that’s with heels on) and can probably leg press a semi. That’s why I call her WFM: she has a high power density just like Vishay’s AEC-Q200 qualified WFM Power Metal Plate current sense resistors. WFM series resistors are available in 2010 and 2512 case sizes, with power ratings up to 4 watts and resistance values from 10 to 500 milli-ohms.
The low resistance values minimize losses while higher values replace multiple series resistors and reduce measurement error. Values above 33 milli-ohms use a nickel-chromium alloy for its high-temperature stability and higher element mass, which improves pulse handling capability. The WFM series also includes a copper heat spreader over the resistive element to more efficiently transfer heat into the PCB, enabling the high power density and minimizing hotspots for long-term reliability and resistance stability down to 0.1%.
