This page presents forward voltage/current measurements on 1N400x and other diodes. Both room temperature and temperature data is presented.
22 January 2008. Added data for two additional diode types; added temperature/current data for both an 1N4005 diode and the 2SC1945 RF power transistor. (Click here to jump to temperature/current data.)
Forward Bias Characteristics of 1N400x Family Diodes
I've been looking at a low power HF power amplifier for the last week or so, and it's been quite educational in many aspects. One of many things it has caused me to look at is whether the standard data sheet for a 1N400x diode is accurate when it shows the forward voltage versus current as a single curve for
every member of the family from the lowly 1N4001 through the imperial 1N4007.
Before digging into the diode data, it may be useful to understand why a standard 50/60 Hz power rectifier diode is relevant to a 7 MHz solid state amplifier. The answer is to provide a temperature stable operating point for the amplifier transistor. I can't explain why without at least a few equations, so please try to follow along.
IC is the collector current and IB. These are DC values, hence the use of capital letter for the subscripts, the normal convention when DC values are referenced.
The relationship between the transistor's collector current and the base current is given by the familiar equation: