Passives
Ceramic current sense resistors offer values down to 2.5Ω
Stackpole's CSRF Series utilises foil on ceramic technology to achieve very low values in small chip sizes. The 0.25W rated CSRF0402 - HP, for example, is available in resistance values from 20Ω down to 2.5Ω. TCR ranges from ±400ppm to ±200ppm are possible depending on resistance value with tolerances as low as one percent.
This combination of small size and low value make the CSRF0402 - HP a popular choice for a wide range of portable consumer electronics for power control and battery monitoring.
Pricing for the CSRF0402-HP depends on resistance value, and tolerance and ranges from $0.205 to $0.23 each in full package quantities.