J202 JFET
J202 JFET specification
- J202 is a general-purpose N-channel amplifier JFET device
- Drain to gate voltage (VDG) is 40V
- Gate to source voltage (VGS) is –40V
- Gate to source cutoff voltage (VGS (OFF)) is -0.8 to -4.0V
- Drain gate forward current (IGF) is 50mA
- Power dissipation is (PD) is 625mW
- Zero gate voltage drain current (IDSS) is 9 to 4.5mA
- Junction temperature (TJ) is between -65 to 150℃
- Thermal resistance of the case is 3℃/W
- Forward transfer admittance (YFS) is 1000umhos
- Low-level audio
- High impedance signal source
- High gain signal
J202 JFET PINOUT
| Pin Number | Pin Name | Description |
| 1 | Gate | The gate terminal is used to trigger the device |
| 2 | Source | In the source, terminal current flows out from the JFET |
| 3 | Drain | The drain terminal is the current inlet of the JFET device |
J202 JFET package
The J202 JFET transistor has a TO-92 general purpose package, the TO-92 is a package mainly used for low-power application transistors.
TO-92 transistor package is a tiny device covering made with plastic material which is good heat resistant and lite weighted.
J202 JFET electrical specification and application description
In this section, we explain the electrical specifications of the J202 JFET transistor device.
Voltage specs
The terminal voltage specs of the J202 JFET transistor are a drain to gate voltage is 40V, and the gate to source voltage is -40V, which is the voltage value of the device.
The gate to source cutoff voltage is between -0.8 to -4.0V
Overall voltage values of the J202 JFET show that it is a component having low voltage mainly used for low-power applications.
Current specs
The forward gate current value of J202 JFET is 50mA, the current values of this device indicate, that they may be used for amplifier applications.
Zero gates voltage drain current
The zero gate voltage drain current value is 0.9 to 4.5mA, it is the current value under the special condition where the gate voltage is zero.
Dissipation specs
The power dissipation is 625mW for the J202 JFET device, it is the low value for a semiconductor device.
Junction temperature
The junction temperature of J202 JFET is -55 to +150℃.
Thermal resistance
The thermal resistance of the case J202 JEFT device is 83.3℃/W
J202 JFET DATASHEET
If you need the datasheet in pdf please click this link
J202 JFET EQUIVALENT
The J202 JFET transistor had equivalent devices such as 2N4338, 2N4340, 2N4341, NTE458, J174, and 2N5459.
Each of these JFET transistors had almost the same electrical specifications, so we can use them as the equivalents of J202 JFET.
Before the replacement process, we need to check and verify the physical specs and also voltage specs.
SMD equivalent of J202 JFET
The MMBFJ202 (SOT-23) is the SMD equivalent of J202 JFET.
J202 vs 2N5457 vs J174
In the table below we list and compare the electrical specifications of J202, 2N5457, and J174, this comparison is really helpful for knowing about the device and also for the replacement process
| Characteristics | J202 | 2N5457 | J174 |
|---|---|---|---|
| Drain to gate voltage (VDG) | 40V | 25V | 30V |
| Gate to source cutoff voltage (VGS(OFF)) | -0.8 to -4.0V | -0.5 to -6.0V | 5 to -10V |
| Gate to source voltage (VGS) | -40V | -25V | -30V |
| Gate forward current (IG) | 50mA | 10mA | 50mA |
| Zero gate voltage drain current (IDSS) | 0.9 to 4.5mA | 1 to 5mA | -20 to -100mA |
| Power dissipation (PD) | 625mW | 310mW | 350mW |
| Junction temperature (TJ) | -55 to 150°C | -65 to 150°C | -55 to 150°C |
| Forward transfer admittance (Yfs) | 1000umhos | 1000 to 5000umhos | - |
| Package | TO-92 | TO-92 | TO-92 |
Each of these three J202, 2N5457, and J174 JFET devices had almost the same electrical specifications, so we can say that each of these JFET can use for the same applications.
Characteristics curves of J202 JFET
The figures show the transfer characteristics of the J202 JFET transistor, the graph is plotted with drain current vs gate to source voltage.
In the graph, we can see two sets of the gate to source cutoff voltage values and constant drain-to-source voltage. From the graph, we can see a current dip.
The figure shows the noise voltage vs frequency characteristics of J202 JFET, the graph is plotted with noise voltage vs frequency.
At a constant drain to gate voltage, two drain current values are been referred such as 10mA and 1Ma.
As we can note from the graph, noise voltage decreases when frequency increases.
Applications of J202 JFET transistor
- Preamp circuit apps
- Data amplifier circuit
- Infrared detection circuit
