LM3424 Datasheet, PDF (31/50 Pages) National Semiconductor (TI) – Constant Current N-Channel Controller with Thermal Foldback for Driving LEDs

6. OUTPUT CAPACITANCE
Solve for C_O:
9. LOOP COMPENSATION
ω_P1 is approximated:
The closest capacitance totals 40 µF therefore Δi_LED-PP is:
ω_Z1 is approximated:
T_U0 is approximated:
Determine minimum allowable RMS current rating:
To ensure stability, calculate ω_P2:
The chosen components from step 6 are:
7. PEAK CURRENT LIMIT
Solve for R_LIM:
The closest standard resistor is 0.04 Ω therefore I_LIM is:
The chosen component from step 7 is:
8. SLOPE COMPENSATION
Solve for R_SLP:
Solve for C_CMP:
To attenuate switching noise, calculate ω_P3:
Assume R_FS = 10Ω and solve for C_FS:
The chosen components from step 9 are:
The chosen component from step 8 is:
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