This is a draft cheat sheet. It is a work in progress and is not finished yet.
Variables
P = Power (Watt) |
I = Current (amp) |
R = Resistance (ohm) |
W = Watt |
J = Joule |
S = Second |
V = Voltage (volt) |
Equations
Parallel Resistance |
1 / Rtot = 1/R1 + 1/R2 .... |
Voltage Divider |
Vout = Vin * R2 / R1 + R2 |
Voltage at Middle of divider |
LED Resistor |
R = Vs - Vf / If |
Vs = Source Voltage, Vf = LED Forward Voltage, If = LED desired Current |
Capacitor Parallel |
Ctot = C1 + C2 + C3.... |
Total values are additive |
Capacitor Series |
Ctot = 1/C1 + 1/C2 + 1/C3... |
Power |
P = I^2 * R |
Ohms Law (Voltage) |
V = I * R |
Ohms Law (Resistance) |
R = V / I |
Ohms Law (Current) |
I = V / R |
Wattage |
W = J / S |
Inverting Op Amp Gain |
Gain = Rf / Rin |
Rin = input resistor value, Rf = output resistor value |
Noninverting Op Amp Gain |
Gain = 1 + Rf / Rin |
Rin = input resistor value, Rf = output resistor value |
Conductance |
G = 1 / R |
dB Gain Power |
dB = 10 log(power ratio) |
db Gain Voltage |
dB = 20 log (voltage ratio) |
Units
T |
tera |
10^12 |
G |
giga |
10^9 |
M |
mega |
10^6 |
k |
kilo |
10^3 |
m |
milli |
10^-3 |
u |
micro |
10^-6 |
n |
nano |
10^-9 |
p |
pico |
10^-12 |
f |
femto |
10^-15 |
|
