General Purpose Diode (3-Amp) 1N5401 / 1N5404 / 1N5408, Silicon Rectifier

The 1N5400 series is a family of popular 3A (ampere) general-purpose silicon rectifier diodes, a simple, very common rectifier diode. Often used for reverse voltage protection, a staple for many power, DC to DC step up, and breadboard projects. 1N5401 is rated for up to 3A/100V.

Applications

• Reverse polarity voltage protection

Features

• Low Forward Voltage Drop
• Diffused junction
• High current capability and low forward voltage drop
• High Surge Current Capability overload rating to 200A peak
• Low reverse leakage current

Specifications

• Reverse Voltage Peak / DC Blocking Voltage Peak
  • 1N5401: 100V
  • 1N5408: 1000V
• RMS Reverse Voltage
  • 1N5401: 70V
  • 1N5408: 700V
• Maximum Continuous Forward Current: 3A
• Forward Voltage: 1V
• Peak Non-Repetitive Surge Current: 200A
• Peak Reverse Current: 5uA
• Max Surge Current: 30A
• Termination Style: Through Hole
• Operating Temperature Max: 125°C

Reverse Voltage Rating

A diode allows electrical current to flow in one direction -- from the anode to the cathode. Therefore, the voltage at the anode must be higher than at the cathode for a diode to conduct electrical current.

In theory, when the voltage at the cathode is greater than the anode voltage, the diode will not conduct electrical current. In practice, however, the diode conducts a small current under these circumstances. If the voltage differential becomes great enough, the current across the diode will increase and the diode will break down.

Some diodes -- such as the 1N5401 -- will break down at 100 volts or less. The 1N5408, however, can sustain a peak repetitive reverse voltage of 1000 volts.

 

Forward Current

When the voltage at the anode is higher than the cathode voltage, the diode is said to be "forward-biased," since the electrical current is "moving forward." The maximum amount of current that the diode can consistently conduct in a forward-biased state is 1 ampere.

The maximum that the diode can conduct at once is 30 amperes. However; if the diode is required to conduct that much current at once, the diode will fail in approximately 8.3 milliseconds.

 

Forward Voltage and Power Dissipation

When the maximum allowable consistent current amount is flowing through the diode, the voltage differential between the anode and the cathode is 1.1 volts. Under these conditions, a 1N400x diode will dissipate 3 watts of power (about half of which is waste heat).