General-purpose diodes, such as the 1N400x series, are versatile diodes used in a wide range of applications. They have moderate voltage and current ratings and can handle relatively low to moderate power levels. General-purpose diodes are commonly used for rectification and basic power switching.
Here are some key points about general-purpose diodes:
- A general-purpose diode is a basic semiconductor diode used for general rectification and switching purposes. It is the most common and inexpensive type of diode.
- It allows current to flow in only one direction, from anode to cathode. It blocks current flow in the reverse direction. This property is used for rectification of alternating current to direct current.
- When forward-biased, a small amount of current can flow through the diode. When reverse-biased, only a very tiny amount of reverse leakage current flows.
- Common general-purpose diode types are 1N4001-1N4007, 1N914, and 1N4148. They typically have voltage ratings from 50V up to 1000V and current ratings from 1A to 3A.
- General-purpose diodes are made from silicon and used in a variety of applications like power supplies, DC power source rectification, voltage regulation, signal clipping, logic gates, and more.
- Compared to other diode types, general-purpose diodes have medium switching speeds and a relatively low forward voltage drop. They are not suited for high frequency or high power applications.
- General-purpose diodes are available in through-hole and surface mount packages. Common packages are DO-41 and SOD-123. Larger high current diodes may use the DO-4 or DO-5 package.
What are the examples of high power applications that require diodes other than general-purpose diodes?
- Power Supplies – High current diodes like Schottky diodes are used for their fast switching speeds and low forward voltage drop. Popular types are 1N5817-1N5819.
- Switched Mode Power Supplies (SMPS) – Fast recovery diodes like UF4007 are used to handle the high frequency switching in SMPS.
- AC Power Controllers – Snubber diodes absorb voltage spikes in inductive loads found in motors and solenoids. 1N5282B is a common snubber diode.
- Inverters – High power inverters use fast recovery diodes that can withstand reverse recovery transients. SEMiX 303FB is an example.
- Solar Power Systems – Bypass diodes handle reverse bias and shadowing effects in solar cells. Types like MBRB2045CT are designed for this.
- RF Generators – PIN diodes are used for their fast switching speed in high frequency RF signal generation. Popular PIN diodes are MA4P7470 and MA4GP907.
- Power Line Surge Protection – Avalanche diodes like 1.5KE18CA can absorb short duration high power surges and transients.
- High Current Rectifiers – Rectifier diodes meant for kilowatt level supplies use specialized high current packages. V25SQ15 is one example.