For Consumer / IoT
LDO Linear RegulatorsHow to use
Line regulation refers to what extent the output voltage varies as the input voltage changes.
The following figure describes a specification example of line regulation.
|ΔVOUT / ΔVIN||Line Regulation||Set VOUT + 0.5 V ≤ VIN ≤ 5.25 V, VIN ≥ 1.4 V||0.02||0.10||%/V|
|Symbol||ΔVOUT / ΔVIN|
|Test Conditions||Set VOUT + 0.5 V ≤ VIN ≤ 5.25 V, VIN ≥ 1.4 V|
This figure suggests that when the input voltage within the range mentioned in the condition changes by 1 V, the output voltage varies by typically 0.02 % / maximum 0.10%.
With an example of a 1.8 V output LDO regulator whose input voltage varies from 3 V to 4.2 V, the extent of variations of the LDO output voltage by line regulation can be estimated as below:
|Typ.||0.02%/V × 1.2 V = 0.024%||1.8 V × 0.024% = 0.432 mV|
|Max.||0.10%/V × 1.2 V = 0.12%||1.8 V × 0.12% = 2.16 mV|
In short, by the input voltage difference between 3 V and 4.2 V, the 1.8 V output changes by typically 0.432 mV / maximum 2.16 mV. The output voltage may be affected both positively and negatively.