Home   » Component data   » JFET data » this page

LSK189 JFET Data

Data for the LSK189 JFET including electrical parameters, maximum current and voltage, pin connections, package type and many other datasheet details.



Key details and performance parameters for the LSK189 JFET.


LSK189 JFET datasheet parameters & data
 
Parameters Details
Brief description Low noise, low capacitance N-channel JFET
Package type TO92 and SOT23
Operational mode
Channel type N-channel
Drain to Source voltage VDSS
Drain to gate voltage VDGR
Gate to source breakdown voltage VGSS -60V
Gate to source pinch-off voltage VGS(OFF) -1.5 min, -3.5V max
Gate to source operating voltage VGS -0.5 min, -3.5V max
Drain source saturation current IDSS 2.5mA min, 5mA typ, 15mA max
Gate operating current IG -2pA typ, -25pA max at VDG = -15V and VGS = 0V
Gate to source leakage current IGSS -100pA max at VDS = -15V
Transconductance gFS 1500µS min at VDS = 15V and VGS = 0V
1000µS min and 1500µS typ at VDS = 15V and ID = 500µA
Output conductance gFS 40µS min at VDS = 15V and VGS = 0V
Noise figure
Common source input capacitance CISS
Common source reverse transfer capacitance CRSS
TJ °C 150°C
PTOT mW 300mW

    Outlines & pinout:

 

 



Explanation of JFET parameters


Parameter Explanation
Operational mode This details whether the FET is an enhancement or depletion mode
Channel type The channel of the JFET can either be an N-type channel where electrons are the majority carriers or P-type where holes are the majority current carrier.
Drain to Source voltage VDSS This is the maximum voltage that can be sustained between the drain and source
Gate to source voltage VGSS This is the maximum voltage that can be sustained between the drain and the gate.
Maximum drain current continuous ID This is the maximum current that can be carried byt he device. Sometimes there may be a differentiation between the continuous and pulsed or peak values

Parameter Explanation
Zero gate voltage drain current IDSS This is the current carried by the device when the gate voltage is zero. The test conditions are normally stated for this.
Gate threshold voltage VGS(th) This is the minimum gate-to-source voltage, VGS required to create a conductive channel between the source and drain terminals
Static drain source ON resistance RDS(ON) This is the resistance of the device when turned on. The test conditions of voltage and current are normally given for this.
Drain source ON voltage VDS(ON) This is the voltage across the device when it is turned on. Again the test conditions are given.
Forward transconductance gFS Forward transconductance also given the letters gm is defined as the change in drain current (ΔID) for a small change in the gate-source voltage ΔVGS, with the drain-source voltage, VDS held constant.

These are the main JFET parameters that have been included in our list. There are others, but these are the main ones and they help quantify the main elements of the performance.

 

Read more about . . . . FET Specifications & Parameters.


Please note, that the data given is the best estimate we can give within a tabulated summary of this nature. Parameters also vary between manufacturers. Electronics Notes cannot accept any responsibility for errors, inaccuracies, etc, although we do endevaour to ensure the data is as accurate as possible.



Notes and supplementary information

 

  •   Availability & sources

The LSK189 is available from a number of stockists and electronic component distributors many of which are given in the table below.


LSK189 Component Distributor, Stock and Pricing

 


  •   Further details

The LSK189 is an N-Channel Junction Field-Effect Transistor (JFET) specifically designed for ultra-low noise and low input capacitance applications. Its key characteristics make it ideal for circuits where signal integrity and minimal added noise are paramount.

Typical applications for the LSK189 JFET include:

  • Ultra-Low Noise Audio/Acoustic Applications:   This is one of its primary uses, including:

    • Microphone preamplifiers:   Its low noise figure (e.g., 1.8 nV/√Hz typical noise) allows for the amplification of very weak audio signals without introducing significant hiss or distortion.

    • Phono preamplifiers:   Critical for high-fidelity audio systems to amplify the delicate signals from record players.

    • High-quality audio amplification:   Used in various stages of high-end audio equipment where noise performance is crucial.

  • Precision Instrumentation:

    • Electrometers:   Devices that measure very small electrical charges or currents, requiring extremely high input impedance and low leakage current.

    • Piezoelectric sensor preamplifiers:   Piezoelectric sensors generate small voltage signals that need to be amplified with minimal noise.

    • Front-end for low-noise operational amplifiers (op-amps):   JFETs like the LSK189 are often used as input stages for op-amps to achieve higher input impedance and lower noise than what the op-amp alone might provide.

  • High-speed temperature-compensated single-ended input amplifiers.

    • High Input Impedance Amplifiers:   JFETs inherently offer very high input impedance, making them suitable for buffering signals from sources that cannot drive a low-impedance load without significant voltage drop or distortion.

    • Impedance Converters:   Transforming a high-impedance signal source to a lower impedance for subsequent stages.

    • Wideband Differential Amplifiers:   Its low capacitance helps maintain good high-frequency performance in differential amplifier configurations.

Ian Poole   Written by Ian Poole .
  Experienced electronics engineer and author.




    Return to Component Data menu . . .