A higher-voltage capacitor is a valid substitute and runs less stressed, so this only
ever adds candidates: rows keep the exact rating whenever one is in stock, and
fall back to the nearest higher one when it isn't. Watch the physical size — a higher-rated can is
sometimes taller. Set a row's voltage max to cap it, or its voltage policy to
exact to leave that row alone.
Preferring manufacturers, high temperature or long life narrows the search: expect a
pricier kit, and some values aren't stocked above a bar at all
— those rows come back empty and need a second pass. To lift one bar for one row, set that row's
policy column to any in the table editor. Rated life is measured at a temperature, so
ticking long-life alone means 5000 hours at 85°C.
🌊 About ripple current
The ripple policy column lets you select capacitors for their
ripple-current handling.
Ripple current is a rating, not a defect — it tells you how much
AC current a capacitor can carry continuously without overheating. Higher is generally better,
so "low ripple" and "high ripple current" are the same request said from
opposite ends. For otherwise comparable parts, higher ripple-current capability usually goes
with lower ESR; lower ESR reduces the ESR component of ripple voltage and, just as importantly,
reduces self-heating.
Set it per row, on purpose. Ripple current matters mainly for
reservoir and smoothing capacitors after a rectifier, and for capacitors carrying substantial
switching ripple in SMPS and deflection circuits. It is usually not a useful selection criterion
for small coupling, bypass, or signal-decoupling capacitors. Asking for a high ripple-current
rating there can simply steer the BOM toward larger, more expensive parts without a practical
benefit. Add the ripple policy column in the table editor and set it only on rows where
the capacitor carries meaningful ripple current.
The two ripple choices answer different questions. Mains rectifier
targets the low-frequency ripple associated with rectified mains — typically 100/120 Hz after
full-wave rectification, depending on 50/60 Hz mains. Switching or scan targets
the kHz-range ripple found in switch-mode supplies and circuits such as monitor deflection
stages. The same capacitor can have different ripple-current ratings at different frequencies
because ESR changes with frequency, so a part that is excellent at one frequency may not be the
best choice at another.
This is a preference, not a hard filter. It only ranks parts that
already meet the other electrical and mechanical requirements, so a row cannot
fail selection because of ripple policy. Expect to pay roughly proportionally for extra
headroom — measured at about 1.8× the price for 1.8× the rating across a small
sample — but treat any such multiplier as a heuristic rather than a guarantee.
Also keep capacitance separate from ripple current. The bulk voltage sag between
charging pulses is primarily determined by capacitance and load current; a like-for-like recap
therefore preserves that basic behavior. What a higher-ripple/lower-ESR part improves is the
ESR-related ripple, current spikes, transient behavior, and the heat generated inside the
capacitor.