Essentially, the IGBT switch is a MOSFET with additional layer in series with the collector, which implies that it could be simulated as a power MOSFET1 and a bipolar PNP transistor
The 3STL2540 is a -40V/-5A PNP transistor
capable of full saturation with maximum voltage drop of 200mV at only 10mA base current.
The Hall-effect switches are available with either current sinking (NPN transistor) or current sourcing (PNP transistor
) output stages.
In addition, spiral inductors, nitride capacitors, three types of poly resistors, a lateral pnp transistor
, RF- and DC-electrostatic discharge protection, and varactor diodes are incorporated in the present technology.
It is possible to use a silicon pnp transistor
with low saturation voltage such as type BCP69 or BCP72 devices to switch the drain current off during the receive mode and nonactive time slots.
Figure 2A shows the current booster with an NPN transistor and Figure 2B with a PNP transistor
. The principle of operation of the two circuits is basically the same except for the polarity of current.
Linear Technology has announced its LT3464 micropower boost converter with an integrated Schottky diode and output disconnect PNP transistor
. The converter uses a current limited, constant ott-time switching topology with an 85 mA intemal switch to deliver voltages up to 34V.
For these reasons the designer must ensure that the gain of the PNP transistor
be reduced by bypassing the collector and the emitter side of the PNP, and possibly the base.
They have two threshold outputs, PNP transistors
or galvanic isolation.
Zetex added a pair of low voltage PNP transistors
to its line of low saturation, high current SOT23FF devices.
Also, [[beta].sub.p] is the current gain of the PNP transistors
When filter capacitor equivalent series resistance (ESR) is at its highest and the gain of PNP transistors
in the control circuit and reference is at its lowest, start-up problems invariably occur.