Radial-leaded diodes

As one eaii see, the thermal parameters define a physieally different situation. For a radial-leaded diode, the heat ean only be eondueted from the die, via the leads. The thermal resistanee would then ehange as a funetion of lead-length and is published this way in data sheets. The thermal expression (see Figure A-6a) is... 

There are some heatsinks for radially-leaded diodes that solder to one of the leads. These are also available from the transistor heatsink manufaeturers. In this situation the thermal equation (see Figure A-6b) beeomes... 

Radial Leaded Components. The target condition for vertical radial components is that the body is perpendicular to the PCB and the component base is parallel to the PCB. It is an acceptable condition to have the component tilt from the perpendicular as long as it does not violate electrical clearance. The space between the component base and PCB should be between 0.3 and 2.0 mm (see Fig. 52.16) but it is considered a process indicator only if it exceeds that dimension. Some components, such as light-emitting diodes (LEDs) and switches, may need to be perpendicular due to mating requirements. 

Valve-Less Rectification Pumps, Figure 6 A simple version of the vortex diode. At left is the closed state with rotation in the vortex chamber at right is the easy flow, open state with radial forward flow. High-performance diodes have several tangential inlets info the chamber, resulting in symmetric character of the flow - but lead to an even more difficult spatial layout of the rectifier circuit... 

---