The LRMAP5930 power resistors from TT Electronics, which have low resistance, are made of metal alloy and are capable of current sensing. It targets the automotive and medical industries, focusing in particular on the area of power supplies and motor drives.
These high power shunt resistors are ideal for use in regulating the flow of current, detection of stalled motors and in particular the measurement of how much power is consumed.
As industrial regulations call for more measurement of and reduction in the energy usage, industrial and automotive demand for electrical drives and actuators has seen a corresponding upsurge. The LRMAP5930 power resistor line is compliant with the automotive industry standard AEC-Q200, making it ideal for automotive use, as well as in power supplies, monitoring of batteries, and process control.
The following are some of the salient features of the LRMAP5930 range:
- The resistance ranges from 0.2 mΩ to 2 mΩ
- They display very high stability over longer durations
- They are rated for power up to 15 W
- They can sense current for power electronics
- They are AEC-Q200 qualified
Note 1: Mounted on FR4 board. See Thermal Data and Mounting section for details.
Note 2: Mounted on thermal substrate. See Thermal Data and Mounting section for details.
The following are the overall physical data of the LRMAP5930 power resistor range:
- They offer a range of resistance from 200 μΩ to 2 μΩ
- They have the ability to absorb a high surge of up to 33
- They are surface mounted and have low thermal impedance, which keeps the rise in temperature low, making it more reliable
- The high surge tolerance allows the resistor to function consistently even if there is a power inrush or even a transient momentary short circuit
Additional benefits include the long-term durability of value, of excellent quality, the low TCR (temperature coefficient of resistance), with the low thermal EMF, which all cooperate to minimize the share of this component in the error budget. This will then allow more experimentation with design at other points in the circuit.
If the main requirement of the circuit design is a reliable and accurate AC and DC current sensing up to 200 A in an SMT platform, the LRMAP5930 high power shunt resistor range not only matches but may even surpass the power ratings given by the rival companies for corresponding parts in the majority of ohmic values.
To make it simple to identify each component, the metal shunt parts are labeled 5930, with the alloy type, the ohmic value and the tolerance.
The use of the metal element shunt parts is to resist the action of any industrial solvent used as standard to clean a printed circuit.
The LRMAP5930 high power shunt resistor range is built using an uninterrupted E-beam welded (EBW) precision resistive strip, with different alloys being used as base materials depending on how much resistance value is assigned.
The following is the summary of the performance of the LRMAP5930 high power chip resistors:
Thermal Data and Mounting
Pulse Overload and Performance
The LRMAP5930 series resistors are ideal for IR reflow soldering. The reflow profile suggested for lead-free soldering, to take one example, with the use of the alloy SAC387 (Sn 95.5%, Ag 3.8%, Cu 0.7%) is shown below:
- Preheat at 30-45 s at 180 °C
- Soldering at 20-40 s at 210 °C
- Peak at 260 °C
The procedure for ordering is shown in the illustration below: