Regulator feedback divider
Regulator feedback divider with explicit circuit assumptions and worked equations.
Development preview. Check the assumptions below before relying on a result. Calculations run in your browser.
How it calculates
Output: Vout = Vref(1 + Rt/Rb) + IFB Rt
Top resistor: Rt = (Vtarget − Vref)/(Vref/Rb + IFB)
Assumptions
- Positive IFB flows from the divider node into the regulator FB pin. Reference and resistor tolerances are independent worst-case corners. Cff zero is the divider zero only; regulator loop stability is not inferred.
Worked example
These are the calculator's default inputs. Change any input above to recalculate.
Inputs
- Solve
- analyse
- Feedback reference
- 1.25 V
- Target output
- 5 V
- Top resistor
- 30000 Ω
- Bottom resistor
- 10000 Ω
- FB current flowing into pin
- 0 A
- Resistor tolerance
- 1 %
- Reference tolerance
- 1 %
- Feed-forward capacitor
- 0 F
Results
- Output voltage
- 5 V
- Top resistor
- 30000 Ω
- Minimum output
- 4.87649 V
- Maximum output
- 5.12652 V
- Bottom-divider current
- 0.000125 A
- Top resistor power
- 0.00046875 W
- Feed-forward zero
- No feed-forward capacitor Hz