Tip 142

[davidallancole]

Has anybody used the TIP 142's integrated diode? It has a diode that can be forward biased when a + voltage is applied to the emitter in respect to the collector. Could you not take one of these and place it on the heatsink to to act as a thermal compensator for the bias voltage?

[lineup]

TIP142 ha got one backwards connected diode across C-E.
It is for protect for backwards currents.

This means you should connect one TIP142 the opposite direction
to use this diode, and this TIP142 would not be of any use as a transistor.

Much better to use some other smaller transistor (or diode) for temp compensation.
Can be in TO-126 ot TO-220 case.
I can not see any benefits using diode in TIP142 for this.
Eventhough it is not impossible to do this.

[Tony]

hi,

if you have no other choice, you can do that, but just like lineup says, i say you waste a good transistor.

[davidallancole]

You guys think that its possible, like the diode in a ThermalTrak transistor? Its just that its a waste of a transistor when you can do it with other ways?

[Tony]

Originally posted by davidallancole
You guys think that its possible, like the diode in a ThermalTrak transistor? Its just that its a waste of a transistor when you can do it with other ways?

ThermalTrak is not the same as a TIP142, the diode is integral and internally connected to the collector emitter, unlike in the therlmaltrack where it is uniquely separate.

[CBS240]

Originally posted by davidallancole
You guys think that its possible, like the diode in a ThermalTrak transistor? Its just that its a waste of a transistor when you can do it with other ways?

Perhaps, a Vbe multiplier could be applied? Since you plan on using a transistor anyway, this would be a better application of it and still use it as a transistor.

[Eva]

To make it clear: