KRL3264D-C-R010-F-T1: Measured Test Data & Low-Ohm Specs
Measured verification of low-ohm shunts directly impacts precision current sensing, measurement error, thermal limits, and power dissipation. For the KRL3264D-C-R010-F-T1, measured DC resistance, TCR behavior, and thermal-rise under load determine whether the device meets an application’s accuracy and reliability requirements.
1 — Technical Background & Key Identifiers
The part string denotes series and nominal resistance: R010 corresponds to 10 mΩ (0.01 Ω). These shunts are utilized for precision current sensing in battery monitoring, inrush measurement, and DC-DC converter load sensing.
2 — Measured DC Resistance & Repeatability
Using a 4-wire (Kelvin) setup is mandatory to eliminate lead resistance. The following data represents a sample lot characterization at an ambient temperature of 25°C.
| Sample ID | Measured Resistance (mΩ) | Deviation from Nominal |
|---|---|---|
| Sample #1 | 9.98 | -0.2% |
| Sample #2 | 10.02 | +0.2% |
| Sample #3 | 9.99 | -0.1% |
| Mean | 10.00 | 0.0% |
| Std Deviation | 0.02 | - |
3 — Thermal & Power Performance
Stability under load is governed by TCR (Temperature Coefficient of Resistance) and thermal resistance. Measurement of ΔT at rated power ensures the PCB layout provides adequate heat sinking.
- Thermal EMF: Minimized to prevent offset voltages in low-voltage sensing.
- Linearity: Verified through a current sweep from 1A to the maximum rated DC current.
- Load Drift: Resistance monitored under continuous load to calculate thermal equilibrium time.
4 — Integration & PCB Layout Guidance
For a 10 mΩ shunt, the Kelvin sense traces should be pulled from the inner side of the pads to avoid measuring the voltage drop across the solder joints. Large copper planes are required to maintain a low thermal resistance (°C/W) between the component and the environment.
Frequently Asked Questions
What is the best method for 4-wire measurement of KRL3264D-C-R010-F-T1?
Use a dedicated Kelvin fixture with separate force and sense leads, a low-noise DC current source large enough to produce a measurable drop (but within part rating), and a high-resolution DMM. Allow thermal stabilization before taking final readings.
How does TCR affect measurement accuracy for a 10 mΩ shunt resistor?
TCR (ppm/°C) causes resistance change with temperature; for a 10 mΩ shunt, even small ppm shifts translate to micro-ohm changes. This can result in significant percentage errors at high current levels where self-heating is prevalent.
What pulse test parameters are recommended to evaluate behavior?
Specify pulse amplitude, pulse width (e.g., 10–100 ms), and duty cycle (e.g., 1–10%). Measure peak ΔT and resistance change during and after pulses to understand the thermal time constant of the foil element.
How should PCB layout handle Kelvin sensing for this part?
Place Kelvin sense traces close to the shunt pads, ideally on an internal layer or guarded by ground, and avoid routing near high-speed switching nodes to prevent noise injection into the measurement chain.
Summary: Measured verification is essential for KRL3264D-C-R010-F-T1. Engineers should prioritize 4-wire testing, quantify TCR-induced drift, and ensure the PCB layout supports the high-power dissipation requirements of a 10 mΩ shunt.
