I. Overview MP930 is a series of high-power ceramic thick-film resistors from the INFEIMI brand, packaged in TO 220. It features non-inductive, high-power, high-precision, and can be mounted with a heat sink. It is commonly used in high-power scenarios such as current sampling, buffering/absorption, and load management in power supplies, servo systems, and battery equipment.
II. Core Structure and Features Process: Ceramic substrate + thick film resistor layer High-temperature sintering, with the resistor film integrated with the ceramic, resulting in good heat dissipation and high stability.
Package: TO 220 2 (two pins), with a bare ceramic heat dissipation surface on the back, allowing for direct attachment of a heat sink, making installation convenient.
Non-inductive design: Special resistor pattern, extremely low inductance, suitable for high-frequency, switching power supplies, snubber circuits, and RF (up to 500MHz at 50Ω).
Electrical isolation: The resistor body is isolated from the heat dissipation surface with an AC voltage of 1500Vrms, ensuring safety and reliability.
III. Key parameters (typical values) Power: 30W @25℃; derated to 0W at 150℃.
Resistance range: 0.02Ω～4.99kΩ; options as low as 0.01Ω are available, suitable for high-current sampling.
Accuracy: o≥0.05Ω: ±1% (mainstream) o0.02～0.04Ω: ±5% oSome values are optional ±5%/±20%.
Temperature coefficient TCR: -20 to +80 ppm/℃.
Operating temperature: -55℃ to +150℃.
Voltage resistance: 250V.
Dimensions: 10.41 × 3.18 × 16.52 mm (length × width × height).
Environmental protection: RoHS compliant.
IV. Model Naming (Example) MP930 0R50 1% MP930: Series 0R50: 0.5Ω 1%: Accuracy Common Resistance Values: 0.05Ω, 0.1Ω, 0.5Ω, 1Ω, 10Ω, 100Ω, 100kΩ, etc.
- Main functions and applications 1. Current sampling resistor: Accurately detects high currents (low resistance, 1% accuracy, no inductance) in power supplies, servo drivers, and battery management systems (BMS).
- Snubber/Absorbing Resistor: RC absorption and spike suppression (non-inductive, high-frequency) for switching power supplies and IGBT/MOSFET circuits.
- Load/Discharge Resistor: Power supply dummy load, battery discharge, inverter braking (30W high power, heat dissipation available).
- High-frequency / RF resistors: used in radio frequency circuits and matching networks (low inductance, available up to 500MHz).
VI. Advantages Comparison Wirewound Resistors: No inductance, good high-frequency performance, small size; wirewound inductors have large inductance and poor high-frequency performance.
Ordinary thick film: high power, capable of heat dissipation, good isolation; ordinary thick film has low power and cannot be attached with a heat sink.
Metal film: low resistance, high power; it is difficult to achieve 0.01Ω with metal film, and it has low power.
VII. Installation and Heat Dissipation Directly attaching a heat sink: Apply thermal grease on the ceramic surface on the back, secure with M3 screws, which can significantly increase power (e.g., from 30W to 50W+).
Pins: Standard TO 220 pins, with a pitch of 5.08mm, suitable for PCB mounting.