Definition
A resistor is a passive two-terminal component whose only job is to oppose the flow of electric current. That opposition, measured in ohms (Ohm), follows Ohm's Law: the voltage across a resistor equals its resistance multiplied by the current through it (V = I x R). By dissipating energy as heat, a resistor lets a designer control current, set bias points, and create predictable voltage drops anywhere in a circuit.
What resistors do on a hashboard
Across an ASIC miner you will find resistors performing several jobs: current-limiting resistors protect LEDs and sensitive inputs, pull-up and pull-down resistors hold logic and control lines at a defined state, sense resistors (often very low-value, milliohm shunts) let the board measure current by reading the tiny voltage across them, and resistor dividers scale a reference voltage for a regulator or temperature sensor. Most are tiny surface-mount chips marked with a numeric code rather than colour bands.
Diagnosing resistors in repair
Resistors usually fail open (going high-resistance or fully open) rather than shorting, often from heat or a nearby power fault. A multimeter in resistance mode confirms a part is near its rated value; an open zero-ohm jumper or a drifted sense resistor can silently break a control loop or current reading. Because pull-up and divider networks define how a chip is supposed to behave, a misread or burnt resistor can masquerade as a chip fault, so verifying the supporting resistors before condemning an ASIC is a habit worth keeping.
Resistors work alongside other passives and references covered in our entries on the voltage regulator, the multimeter, and the schematic.
In Simple Terms
A resistor is a passive two-terminal component whose only job is to oppose the flow of electric current. That opposition, measured in ohms (Ohm), follows…