online electronic calculator - Ohm's law and much more

RC discharging calculator

Online calculator for formulas used in electronic circuit design and electrical engineering.

Basic electric calculations:

Ohm's Law, Ohm's Law with power, DC power, AC real power, LC resonant frequency, Capacitor charging/discharging, Capacitive reactance, Capacitive current + reactive power, Capacitor energy, Capacitor Δ energy, RC discharging, Inductor square pulse, Inductive reactance, Inductive current + reactive power, Inductor energy, 2 parallel resistors, 3 parallel resistors, System bandwidth, Bandwidth ↔ rise time

Wire and winding calculations:

Diameter ↔ cross section ↔ AWG, Wire resistance, Wire weight, Current density, Wire R thermal drift

Calculate RC discharging: 1000uF, 3kΩ, 5s, 12V, V


A capacitor C discharging via a resistor R for time t. Voltage 1 (V1) is the initial voltage. Voltage 2 (V2) is the final voltage.    C=t/(R.log(V1/V2))    R=t/(C.log(V1/V2))    t=R.C.log(V1/V2)    V1=V2*et/(RC)    V2=V1/et/(RC)
picture of a capacitor discharging via a resistor

Enter any 4 values, the 5th one will be calculated:

Capacitance: -0.1 +0.1 -1 +1 -10 +10 -100 +100
Resistance: -0.1 +0.1 -1 +1 -10 +10 -100 +100
Time: -0.1 +0.1 -1 +1 -10 +10 -100 +100
Voltage 1: -0.1 +0.1 -1 +1 -10 +10 -100 +100
Voltage 2: -0.1 +0.1 -1 +1 -10 +10 -100 +100
Output metric prefix:   Automatic    User-selected
 

Standard EIA Decade Values of capacitors - decade 1 to 10 mF

E6E12E24
1.0 mF
1.5 mF
2.2 mF
3.3 mF
4.7 mF
6.8 mF
1.0 mF, 1.2 mF
1.5 mF, 1.8 mF
2.2 mF, 2.7 mF
3.3 mF, 3.9 mF
4.7 mF, 5.6 mF
6.8 mF, 8.2 mF
1.0 mF, 1.1 mF, 1.2 mF, 1.3 mF
1.5 mF, 1.6 mF, 1.8 mF, 2.0 mF
2.2 mF, 2.4 mF, 2.7 mF, 3.0 mF
3.3 mF, 3.6 mF, 3.9 mF, 4.3 mF
4.7 mF, 5.1 mF, 5.6 mF, 6.2 mF
6.8 mF, 7.5 mF, 8.2 mF, 9.1 mF

Other capacitance decades:

1 - 10 pF, 10 - 100 pF, 100 - 1000 pF, 1 - 10 nF, 10 - 100 nF, 100 - 1000 nF, 1 - 10 uF, 10 - 100 uF, 100 - 1000 uF, 1 - 10 mF, 10 - 100 mF, 100 - 1000 mF, 1 - 10 F, 10 - 100 F, 100 - 1000 F, 1 - 10 kF, 10 - 100 kF, 100 - 1000 kF,

Standard EIA Decade Values of resistors - decade 1 to 10 kΩ

E6E12E24
1.0 kΩ
1.5 kΩ
2.2 kΩ
3.3 kΩ
4.7 kΩ
6.8 kΩ
1.0 kΩ, 1.2 kΩ
1.5 kΩ, 1.8 kΩ
2.2 kΩ, 2.7 kΩ
3.3 kΩ, 3.9 kΩ
4.7 kΩ, 5.6 kΩ
6.8 kΩ, 8.2 kΩ
1.0 kΩ, 1.1 kΩ, 1.2 kΩ, 1.3 kΩ
1.5 kΩ, 1.6 kΩ, 1.8 kΩ, 2.0 kΩ
2.2 kΩ, 2.4 kΩ, 2.7 kΩ, 3.0 kΩ
3.3 kΩ, 3.6 kΩ, 3.9 kΩ, 4.3 kΩ
4.7 kΩ, 5.1 kΩ, 5.6 kΩ, 6.2 kΩ
6.8 kΩ, 7.5 kΩ, 8.2 kΩ, 9.1 kΩ

Other resistance decades:

10 - 100 mΩ, 100 - 1000 mΩ, 1 - 10 Ω, 10 - 100 Ω, 100 - 1000 Ω, 1 - 10 kΩ, 10 - 100 kΩ, 100 - 1000 kΩ, 1 - 10 MΩ, 10 - 100 MΩ, 100 - 1000 MΩ,

Some common voltages:

Alkaline
Zinc-Carbon
NiMH, NiCd
rechargeable
Li-Ion
3.6V
Li-Ion
3.7V
Li-Ion
full 4.2V
LiFePO4
(LFP) 3.2V
Lead-acid
battery
Power
supply
1-cell: 1.5V
2-cell: 3V
3-cell: 4.5V
4-cell: 6V
5-cell: 7.5V
6-cell: 9V
7-cell: 10.5V
8-cell: 12V
9-cell: 13.5V
10-cell: 15V
11-cell: 16.5V
12-cell: 18V
1-cell: 1.2V
2-cell: 2.4V
3-cell: 3.6V
4-cell: 4.8V
5-cell: 6V
6-cell: 7.2V
7-cell: 8.4V
8-cell: 9.6V
9-cell: 10.8V
10-cell: 12V
11-cell: 13.2V
12-cell: 14.4V
1-cell: 3.6V
2-cell: 7.2V
3-cell: 10.8V
4-cell: 14.4V
5-cell: 18V
6-cell: 21.6V
7-cell: 25.2V
8-cell: 28.8V
9-cell: 32.4V
10-cell: 36V
11-cell: 39.6V
12-cell: 43.2V
1-cell: 3.7V
2-cell: 7.4V
3-cell: 11.1V
4-cell: 14.8V
5-cell: 18.5V
6-cell: 22.2V
7-cell: 25.9V
8-cell: 29.6V
9-cell: 33.3V
10-cell: 37V
11-cell: 40.7V
12-cell: 44.4V
1-cell: 4.2V
2-cell: 8.4V
3-cell: 12.6V
4-cell: 16.8V
5-cell: 21V
6-cell: 25.2V
7-cell: 29.4V
8-cell: 33.6V
9-cell: 37.8V
10-cell: 42V
11-cell: 46.2V
12-cell: 50.4V
1-cell: 3.2V
2-cell: 6.4V
3-cell: 9.6V
4-cell: 12.8V
5-cell: 16V
6-cell: 19.2V
7-cell: 22.4V
8-cell: 25.6V
9-cell: 28.8V
10-cell: 32V
11-cell: 35.2V
12-cell: 38.4V
1-cell: 6V
2-cell: 12V
3-cell: 18V
4-cell: 24V
5-cell: 30V
6-cell: 36V
7-cell: 42V
8-cell: 48V
9-cell: 54V
10-cell: 60V
11-cell: 66V
12-cell: 72V
1.8V
2.5V
3V
3.3V
5V
6V
9V
12V
15V
18V
24V
48V

RC discharging formula says:

•A 1000uF (one thousand microfarads) capacitor discharges via a 3kΩ (three kiloohms) resistor during 5s (five seconds) from 12V (twelve volts) to 2.266507234051V (two point two six six five zero seven two three four zero five one volts).
•To discharge a 1000uF (one thousand microfarads) cap from 12V (twelve volts) to 2.266507234051V (two point two six six five zero seven two three four zero five one volts) in 5s (five seconds), you need a 3kΩ (three kiloohms) discharging resistor.
•Discharging a 1000uF (one thousand microfarads) capacitor from 12V (twelve volts) to 2.266507234051V (two point two six six five zero seven two three four zero five one volts) using a 3kΩ (three kiloohms) resistance will take 5s (five seconds).
•If a capacitor should discharge from 12V (twelve volts) to 2.266507234051V (two point two six six five zero seven two three four zero five one volts) via 3kΩ (three kiloohms) in 5s (five seconds), its capacitance would have to be 1000uF (one thousand microfarads).



This is a simple online calculator for formulas used in electronic engineering and design.

This online calculator is for reference only. I do not guarantee it to work correctly. You use this at your own risk only.