Decode capacitor code 472, select C0G vs X7R dielectric, and calculate RC filter cutoffs for the 4.7nF capacitor — practical guide from a PCB engineer’s perspective.

The 4.7nF capacitor is one of those parts that sits in the E12/E24 standard value series and gets pulled into designs constantly — from ADC anti-aliasing filters and RF snubbers to debounce networks and CFL ballasts. Yet when a junior engineer looks at the body of a ceramic disc and sees 472, confusion often follows. What does it mean, and what can this capacitor actually do for your circuit?

This guide answers both questions from the ground up. By the end, you’ll know how to decode the marking, select the right dielectric, calculate RC filter cutoff frequencies, and lay the part out correctly on your PCB.

Decoding Capacitor Code 472: What Does It Mean?

The EIA three-digit marking system is straightforward once you know the rule: the first two digits are significant figures, and the third digit is the power-of-ten multiplier in picofarads.

Digit	Value	Meaning
1st	4	First significant figure
2nd	7	Second significant figure
3rd (multiplier)	2	× 10² = × 100
Result	4700 pF = 4.7 nF = 0.0047 µF	All equivalent

So 47 × 100 = 4700 pF = 4.7 nF. Simple as that. You’ll see this part listed under all three unit conventions depending on the distributor. They are identical — 4.7 nF, 4700 pF, and 0.0047 µF are the same capacitance.

One trap to watch for: 473 is not the same as 472. The 473 decodes to 47 × 1000 = 47,000 pF = 47 nF — a full ten times larger. Getting these mixed up on a BOM is a real design risk, especially when similar-looking parts sit next to each other in a reel drawer.

A tolerance letter suffix usually follows the three digits. J = ±5%, K = ±10%, M = ±20%. The voltage rating may also appear as a prefix letter-number pair (e.g., 2A = 100 VDC per EIA standard), though on smaller disc ceramics this is often absent — check the datasheet or reel label.

4.7nF Capacitor Full Specifications

Parameter	Typical Values
Capacitance	4.7 nF (4700 pF / 0.0047 µF)
EIA Marking Code	472
Common Dielectrics	C0G/NP0, X7R, Y5V
Voltage Ratings	16V, 25V, 50V, 100V, 250V, 400V, 1000V+
Tolerance	±5% (J), ±10% (K), ±20% (M)
SMD Packages	0402, 0603, 0805, 1206
Through-Hole Packages	Radial disc, film (5mm, 10mm pitch)
ESR	Low — suitable for RF and high-frequency circuits
Polarised?	No — non-polarised in all types

Choosing the Right Dielectric for Your 4.7nF Capacitor

This is where component selection either goes right or quietly causes you a re-spin six months down the road. The dielectric you choose defines how the 4.7nF capacitor will actually behave in your circuit — not just at room temperature on the bench, but across its entire operating range.

C0G / NP0 — The Precision Choice

C0G (also called NP0) is a Class 1 dielectric with a temperature coefficient typically within ±30 ppm/°C. In practice this means negligible capacitance change over −55°C to +125°C, no measurable aging, and no voltage-dependent capacitance shift. The dissipation factor is also extremely low (maximum 0.15%), which translates to minimal signal loss at high frequencies.

For any 4.7nF capacitor that sits in a timing circuit, oscillator feedback network, precision analog filter, or RF tuning stage, C0G is the correct choice. Yes, it’s slightly larger for a given capacitance-voltage combination compared to X7R, but in the nF range this is rarely a problem. You can fit a C0G 4.7nF in an 0603 package at 50V without issue.

X7R — Workhorses for General-Purpose Filtering

X7R allows ±15% capacitance variation over −55°C to +125°C, and it ages logarithmically — roughly 1–2% capacitance loss per decade-hour. For non-critical decoupling, power supply bypass, or filtering stages where the exact −3dB point doesn’t need to be tightly controlled, X7R is cost-effective and compact.

However, be conscious of DC bias derating. An X7R 4.7nF capacitor rated at 50V can lose a significant portion of its nominal capacitance when operated at a high fraction of its rated voltage. Always check the manufacturer’s DC bias curve in the datasheet, not just the nominal value.

Y5V / Z5U — Avoid for Signal Work

Capacitance can vary by as much as −82% across the operating temperature range. Not appropriate for filters, timing, or any circuit where the RC time constant must be predictable. Reserve these for bulk energy storage where capacitance tolerance is irrelevant to function.

Dielectric Selection Summary

Dielectric	Temp Stability	Aging	DC Bias Effect	Best For
C0G / NP0	±30 ppm/°C	Negligible	None	Filters, timing, RF, oscillators
X7R	±15% over range	~1–2%/decade	Moderate	General decoupling, bypass
Y5V	+22% / −82%	High	Significant	Bulk storage only

RC Filter Design with a 4.7nF Capacitor

The core formula for an RC filter cutoff frequency is:

fc = 1 / (2π × R × C)

With C = 4.7 nF, this gives the following −3 dB cutoff frequencies across standard resistor values:

Resistor (R)	Cutoff Frequency (fc)	Suggested Application
33 Ω	~1.02 MHz	HF RF snubber, EMI suppression
100 Ω	~338 kHz	High-speed signal line filtering
1 kΩ	~33.8 kHz	ADC input conditioning
3.38 kΩ	~10 kHz	Audio band low-pass
10 kΩ	~3.38 kHz	Mid-frequency signal filtering
33.8 kΩ	~1 kHz	Low-frequency anti-aliasing
100 kΩ	~338 Hz	Audio high-pass, DC blocking

At the cutoff frequency, output voltage is at 70.7% (−3 dB) of input. Below that for a low-pass filter, the signal passes through with minimal attenuation. Above it, roll-off occurs at −20 dB per decade for a single-pole stage.

How to Reverse-Calculate the Resistor for a Target Cutoff

Rearranging the formula: R = 1 / (2π × fc × C)

Example: You need a 5 kHz low-pass filter with your 4.7nF capacitor:

R = 1 / (2π × 5000 × 4.7×10⁻⁹) = 6.76 kΩ

The nearest E24 standard value is 6.8 kΩ, which gives a cutoff of approximately 4.98 kHz — effectively spot on.

RC Time Constant for Timing Circuits

For timing applications, the time constant τ = R × C determines how quickly the capacitor charges to ~63.2% of supply voltage:

Resistor (R)	Time Constant (τ)	Typical Use Case
1 kΩ	4.7 µs	High-speed pulse timing
10 kΩ	47 µs	Mid-range timing, debounce
47 kΩ	220.9 µs	Oscillator RC networks
100 kΩ	470 µs	Timer stages, 555 astable
470 kΩ	2.209 ms	Slow timing intervals

A complete charge cycle is conventionally taken at 5τ (~99.3%). If you’re using the 4.7nF with a 555 timer, pairing it with a 47 kΩ resistor puts your oscillation frequency in the tens of kilohertz range — a common sweet spot for tone generators and basic PWM.

Where the 4.7nF Capacitor Gets Used on Real PCBs

The 4.7nF capacitor covers a distinctive frequency territory that makes it a regular fixture in several circuit categories:

ADC anti-aliasing filters are one of the most common placements. High-speed ADCs typically require a low-pass RC filter at the input to prevent frequency aliasing. The 4.7nF paired with a resistor in the 1–10 kΩ range covers the audio-to-RF boundary well.

RF and microwave snubbers use the 4.7nF to suppress switching transients on gate drive lines and MOSFET drain nodes. At these frequencies, low ESR is critical — use C0G ceramic in 0402 or 0603.

I²C and SPI bus filtering in noisy industrial environments often benefits from a small capacitor to ground on each signal line. The 4.7nF is a common choice here because it provides good HF suppression without visibly slowing down the signal edges at standard bus speeds.

**CFL ballast networks