
	Where results make sense

Topic: JFET

Related Topics

Field effect transistor

MOSFET

Bipolar junction transistor

MESFET

HEMT

IGBT transistor

Elpidio Quirino

	Line defects
		The figure of merit, Gfs, that is the ratio of drain-source current to gate voltage is the JFET transconductance.
		In the junction FET (JFET), the gate material is made of the opposite polarity semiconductor to the channel material (for a P-channel FET the gate is made of N-type semiconductor material).
		The magnitude of the reverse bias at the junction is proportional to the size of the electric field that 11 pinches" the channel.
	www.mtmi.vu.lt /pfk/funkc_dariniai/transistor/fet.htm (1265 words)

	The Junction Field Effect Transistor or JFET - www.SiliconFarEast.com
		(JFET) is another type of FET, a basic structure of which may consist of a semiconductor bar with ohmic contacts at the end and heavily doped regions on its opposite sides.
		The heavily doped regions on the sides of the bar are connected to serve as the gate of the JFET.
		The JFET structure described above is no longer practical to use because of the difficulty with having to diffuse dopants from two opposite sides of a bar.
	www.siliconfareast.com /jfet.htm (310 words)

	NationMaster - Encyclopedia: JFET
		The JFET gate presents a small current load which is the reverse leakage of the gate-to-channel junction.
		The JFET had been predicted as early as 1925 by Julius Lilienfeld, and the theory of operation of the device was sufficiently well known by the mid 1930's for a patent to be issued for it.
		In the junction FET (JFET), the gate material is made of the opposite polarity semiconductor to the channel material (for a P-channel FET the gate is made of N-type semiconductor material).
	www.nationmaster.com /encyclopedia/JFET (1548 words)

	JFET
		flow from source to drain in a JFET is restricted when a voltage is applied to the gate The junction gate field-effect transistor (JFET or JUGFET) is the simplest type of field effect transistor.
		The JFET consists of a long channel of semiconductor material.
		The flow of water through a garden hose can be controlled by squeezing it and reducing its cross section; the flow of electric charge through a JFET is controlled by constricting the cross section of the current-carrying channel.
	www.xasa.com /wiki/en/wikipedia/j/jf/jfet.html (394 words)

	N-JFET - Electronic Circuits Projects Diagrams Free (Site not responding. Last check: 2007-10-19)
		Jfets conduct as hard as they can with the lowest resistance from drain to source when the gate voltage equals the source voltage.
		Since the source is made from N material in an N-channel Jfet you don't want its P material gate to be positive with respect to the N material source or the diode would conduct, ruining the very high impedance at the gate.
		To avoid loss when the Jfet is on, the output needs a fairly high impedance load which causes poor attenuation at high frequencies when the Jfet is off due to the capacitance across the Jfet.
	www.electro-tech-online.com /general-electronics-chat/15314-n-jfet.html (1091 words)

	JFET (JUNCTION-GATE FIELD-EFFECT TRANSISTOR)
		JFETs are always in ‘ON’ state until a gate voltage is applied.
		The JFET gates should always be reverse biased, as forward bias voltages greater than 50mA may burn the JFET.
		JFETS can be symmetric, where connection to source and drain can be interchanged, or asymmetric, where the two terminals cannot be interchanged.
	www.partminer.com /glossaryhtml/jfet_junction_gate_field_effect_transistor.htm (318 words)

	JFET Doubler
		JFETs being isolated devices won't have either the connection problems - or the inherent matching.
		The inclusion of R15 (1K) ensures that the stage can drive reasonable loads out of it (see the article on JFET pairs and gain stages) instead of being loaded into low gain as a bare mu-amp can be (see the original National Semiconductor app note for more on the JFET mu-amp).
		Q4 and Q5 are biased by R10 and R11, with the bias voltage filtered by C6 and isolated for signal purposes by R12.
	www.geofex.com /Article_Folders/jfetdoub/jfetdoub.htm (1216 words)

	JFET symbols and bias voltages
		The P-channel JFET therefore requires a positive gate voltage to be reverse biased, and current flows through it from drain to source.
		On the positive alternation of the input signal, the amount of reverse bias on the P-type gate material is reduced, thus increasing the effective cross-sectional area of the channel and decreasing source-to-drain resistance.
		On the negative alternation of the cycle, the amount of reverse bias on the gate of the JFET is increased and the action of the circuit is reversed.
	www.tpub.com /neets/book7/26j.htm (882 words)

	JFET
		The current flow between source and drain is controlled by the gate voltage.
		In a JFET device, the gate voltage is applied to the channel across a P-N junction, in contrast to its application across an insulator in a conventional MOSFET.
		JFETs are of both P-channel and N-channel types.
	encyclobeamia.solarbotics.net /articles/jfet.html (91 words)

	The Junction Field Effect Transistor (JFET) (Site not responding. Last check: 2007-10-19)
		JFETs come in two types: N-channel and P-channel, and are shown in figure 5.14.
		Since the channel is formed from a single-polarity (unipolar) material, its resistance is a function only of the geometry of the conducting volume and the conductivity of the material.
		The JFET operates with all PN junctions reverse-biased so as to obtain a high input impedance into the gate.
	www.piclist.com /images/ca/ualberta/phys/www/http/~gingrich/phys395/notes/node88.html (174 words)

	CiteULike: A SiC JFET driver for a 5 kW, 150 kHz three-phase PWM converter (Site not responding. Last check: 2007-10-19)
		Presently the JFET is the only controlled turn off/on SiC device that is close to commercialization and available as restricted samples.
		However the JFET is a normally-on device that requires a negative gate voltage to turn off.
		This paper presents a description of the JFET semiconductor structure, and the SiC JFET's static and dynamic characteristics from room temperature to 200 /spl deg/C. A SiC JFET gate driver circuit is presented and its performance described.
	www.citeulike.org /user/dlugo/article/668359 (553 words)

	JFET characteristics (Site not responding. Last check: 2007-10-19)
		In the region shown with a green background the drain-source voltage is small and the channel behaves like a fairly ordinary conductor.
		In this region the current varies roughly in proportion to the drain-source voltage as if the JFET obeys Ohm's law.
		For a power JFET the currents would be perhaps up to tens of amps rather than a few tens of milliamps.
	www.st-andrews.ac.uk /~jcgl/Scots_Guide/info/comp/active/jfet/jfetchar/jfetchar.htm (322 words)

	Simple JFET Audio Preamps
		Each particular JFET sets a particular output bias voltage, so the JFET must be selected from among multiple devices for the desired bias value.
		JFETs also vary with respect to gain and noise level, so best operation requires some selection there as well.
		The JFET is at the lower left, the PNP at the top, and the emitter-follower NPN at the right.
	www.ciphersbyritter.com /RADELECT/PREJFET/JFETPRE.HTM (1754 words)

	JFET bias question
		Tha'ts what I've done, I ran a 100kB's wiper lug to wire to clip, and an outside lug to wire to V+...then biased each jfet with the pot, pulled the clipped end to measure the pot only, replace with resistor or resistors to match the R found in the pot.
		A important point as I have always thought that 4.5 was the holy grail of performance but I have found with trims MAN you can really change the quality and the etc.....of the scheme you are building....
		For amp emulations with multiple JFET gain stages, the trim pots are critical to getting that sweet sound, or many different variations.
	www.diystompboxes.com /smfforum/index.php?topic=46627.msg343045 (831 words)

	Current overload protected solid state relay - Patent 4581540
		A resistor 72 is connected between the gate terminals of the the JFET 70 and the MOSFET 38, and a capacitor 74 is connected between the gate and source terminals of the JFET 70.
		A resistor 76 is connected between the drain terminals of the MOSFET 38 and the JFET 70.
		With the capacitor 74 fully discharged, the JFET 70 is in a conducting state.
	www.freepatentsonline.com /4581540.html?highlight=4363068 (4496 words)

	JFET Increases Voltage Rating for Linear Regulator - Maxim/Dallas (Site not responding. Last check: 2007-10-19)
		Connecting the external JFET extends the circuit's input-voltage limit to the JFET's gate-source breakdown voltage.
		Replacing the J106 with a 2N4391 JFET increases the allowable input voltage to 40V.
		Adding a JFET in cascode with a linear-regulator IC extends the allowable input voltage to 25V or 40V, depending on the JFET device used.
	www.maxim.de /appnotes.cfm/appnote_number/482 (247 words)

	Principles of Operation
		Just as for a simple diode, the depletion region grows as the reverse bias across the PN junction is increased, thereby constricting the cross section of the conducting N-channel material and increasing the resistance of the channel.
		The characteristic curves of a typical JFET are shown in figure 5.16.
		This is the pinch-off region, where the JFET can be used as a linear voltage and current amplifier.
	www.sxlist.com /images/ca/ualberta/phys/www/http/~gingrich/phys395/notes/node89.html (279 words)

	JFET current regulator - Chapter 5: DISCRETE SEMICONDUCTOR CIRCUITS - Volume VI - Experiments (Site not responding. Last check: 2007-10-19)
		Instead, it is a JFET with a fixed resistance connected between the gate and source terminals:
		A normal PN-junction diode is included in series with the JFET to protect the transistor against damage from reverse-bias voltage, but otherwise the current-regulating facility of this device is entirely provided by the field-effect transistor.
		JFET current regulator vsource 1 0 rload 1 2 4.5k j1 2 0 3 mod1 rlimit 3 0 1k.model mod1 njf.dc vsource 6 12 0.1.plot dc i(vsource).end
	www.allaboutcircuits.com /vol_6/chpt_5/15.html (1018 words)

	Biasing Op-Amps into Class A
		An N-channel JFET saturates when the gate to source voltage is 0V, which you can achieve simply by tying them together.
		The other benefit of using a JFET instead of a plain resistor is that the input impedance of a JFET is up in the megohms range, so the op-amp still sees a near-ideal load situation.
		Neither JFET is helping the other in this situation, so the combination has about the same performance as the lone JFET (-2.4%/+1.5% in my test), only now you're using more parts to achieve that performance level.
	www.tangentsoft.net /audio/opamp-bias.html (2854 words)

	JFET
		However, instead of being both on the same surface, as with a MOSFET, the two regions are opposite one another on either side of the crystal.
		Thus, a more accurate depiction of the JFET would be what is shown in Figure 3.
		You must make sure that the gate-substrate junction always remains reverse biased, and since the JFET can only be a depletion-mode device, you have to have a voltage on the gate if you want to turn the transistor off.
	cnx.org /content/m1030/latest (487 words)

	EB-2000/402 SE Balanced ALL-JFET Lineamp
		The SE Balanced ALL-JFET lineamp is a very musical amplifier.
		The basic circuit was published in the 6/99 issue of Audio Electronics, see copy on this homepage under “Special articles”.
		We have upgraded the basic design with new constant current source and complementary JFET output stage, and is now available in Kit form under the designation: EB-2000/402.
	www.borbelyaudio.com /eb2000402.asp (121 words)

	Pendulum PL-2 JFET/MOSFET Analog Peak Limiter
		JFET (hard) or MOSFET (soft) peak limiting modes
		The PL-2 has two modes of peak limiting, using either junction field-effect transistors (JFET) or metal-oxide semiconductor field effect transistors (MOSFET) as the control elements.
		The JFET tends to be a stiffer, harder mode of limiting, while the MOSFET has a softer, more compliant response.
	www.pendulumaudio.com /PL2.html (294 words)

	MOXTEK® XRF X-ray Products: Tubes, Detectors, Beryllium/Polymer xray Windows, JFET; Optics: Infrared/Ultraviolet ...
		The x-ray and optics divisions at MOXTEK® manufacture and develop x-ray and optical components for a variety of applications.
		MOXTEK was one of the first companies to produce miniature x-ray tubes.
		In addition, MOXTEK manufactures ultra-thin films, specialty coatings, ultra-low noise electronics, junction field effect transistors (JFET), Beryllium and ultra thin polymer (ProLINE) x-ray windows, and Si-PIN detectors, and other radiation detectors.
	www.moxtek.com (295 words)

	JFET Amplifiers
		Precision, Low Input Bias Current, Wide BW JFET Op Amp (Single)
		Op Amp, 100MHz, JFET Input, High Slew Rate, Uncompensated
		Op Amp, 8MHz, Precision, JFET Input, Unity Gain
	www.chipcatalog.com /Cat/218.htm (78 words)

	SIM910 JFET & SIM911 BJT - Voltage Preamplifiers
		SIM910 JFET and SIM911 BJT - Voltage Preamplifiers
		The SIM910 and SIM911 are low-noise, programmable preamplifiers which are ideal for a wide range of small signal applications.
		The low bias current and 100 MΩ input impedance of the SIM910, which has a JFET front-end, make it a better choice for use with high impedance sources.
	www.thinksrs.com /products/SIM910911.htm (337 words)

	Greatly Improved JFET Matcher is here!
		In practice, accurate JFET matching needs to be done on two different points, since the drain-to-source resistance (Rds) is a function of two parameters related to the manufacturing process: Vp (pinch-off or cutoff voltage) and Idss (drain-to-source saturation current), as indicated by the following equation:
		Some JFETs won't sweep at the same times as others, and some will be completely off or on when the others are sweeping.
		No CMOS...and 90 Jfet transistors for phaser use, plus the 10 that are in the 90 and the SS...hint hint...
	www.diystompboxes.com /smfforum/index.php?topic=29513.0 (2834 words)

Try your search on: Qwika (all wikis)