Online Calculators

I hope that this collection of online calculators will benefit DIYers designing their own circuits. I will add to them as I find calcualtions that meet my own needs

Non Inverting LM3875 Gain Calculator

Justblair

lm3875noninv The LM3875 is a popular amplifier with amateur amplifier builders. This calculator, designed for non-inverting gainclone amplifiers derives the gain given the resistor choices that you make.

A third option allows you to set the High Pass Filter(HPF) for the amplifier. The High pass filter prevents the amplification of DC through the amplifier. Speakers don't like DC. Resistor values are chosen from the E24 range of values. Typical values are shown. The LM3875 is not stable at gains of less than 10x.

No Frames

Write comment (0 Comments)

Tripath 2024 Gain Calculator

Justblair

tripclose1

This calculator will derive the gain and the gain in decibels for the Tripath TA2024 Amplifier Chip.

The T-Class Chips gain is set by two resistors, Ri and Rf. If you insert a value for the input Capacitor Ci this calculator will also supply the High Pass Filter -3db point in Hz. Aim for just less than 5hz.

Values for R1 and Rf are selcted from a list of E24 resistor values and are in Ohm. The capacitor value is expressed in uf

LM317 Voltage Calculator

Justblair

lm317 This LM317 Calculator can be used to choose the correct resistor values for the LM117-LM317 Voltage regulators.

For an LM317, LM217 or LM117 you can either select your resistor values from the E24 decade list to calculate the LM317 output Voltage, or input your target voltage and value for R1 to get a "ideal" R2 resitor value for the LM317. This Ideal resistor of course may not exist, but sometimes can be made up from more than one resistor, or alternatively will allow you to estimate the optimum variable resistor value to fine tune your LM317 circuit.