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## Tools

A series of useful formulae for the electronics engineer:-

### Formula - PPM/DegC

Calculate the change in value of any nominal value (resistance etc) for every degC change.
Note: % = ppm / 10000
 Nominal Value: PPM: Tested range degC: Variation per degC: Min: Max: Variation across tested temp range:

### Formula - Op-Amp Gain (inverting)

 Rf Ohm: Rin Ohm: Gain:

### Formula - Op-Amp Gain (non-inverting)

 Rf Ohm: R3 Ohm: Gain:

### Formula - Time / Hz

Convert Time & Frequency.
 Freq Hz: Period mS:

 Period mS: Freq Hz:

### Formula - mm to mils

mils to mm / mm to mils.
 mm mils

### Formula - Parallel Resistors

 R1: R2: R3: R4: R5: R6: R7: R8: Total Resistance:

### Formula - Voltage Divider

 Input.V: R1 Ohm: R2 Ohm: Output.V:

### Formula - LM317

Fill in the two resistor values(ohms) to compute the output voltage.
 R1 resistor: R2 resistor: Output.V:

### Formula - Ohms Law

Fill in any TWO numeric values and I'll give you all FOUR.
 Volt: Ohm: Amp: Watt:

### Formula - Zener Diode

 Max Input: Volts Min Input: Volts Output: Volts Load: mA Results:
 Resistor - Ohms Resistor - Watts Zener - Volts Zener - Watts