BSS138 MOSFET specification
- BSS138 is an N-channel logic level enhancement mode field effect transistor device
- Drain to source voltage (VDSS) is 50V
- Gate to source voltage (VGSS) is +/- 20V
- Gate to the threshold voltage (VGS (th)) is 8V to 1.5V
- Drain current (ID) is 22A
- Pulsed drain current (IDM) is 88A
- Power dissipation is (PD) is 300mW
- Total gate charge (Qg) is 7 to 2.4nC
- Drain to source on-state resistance (RDS (ON)) 7 to 5.8Ω
- Zero gate voltage drain current (IDSS) is 5uA
- Turn on rise time (tr) is 9 to 18ns
- Turn on fall time (tf) is 7 to 14ns
- Input capacitance (Ciss) is 27pf
- Thermal resistance junction to ambient (Rth j-A) is 350℃/W
- Junction temperature (TJ) is between -55 to 150℃
- High cell density
- DMOS technology
- Designed to minimize on-state resistance
- Fast switching performance
BSS138 MOSFET Pinout
|The gate is used to trigger the MOSFET
|In the source, terminal current flows out from the MOSFET
|The drain terminal is the input of the MOSFET
The BSS138 is a surface-mounted transistor type mainly used to minimize on-state resistance.
BSS138 MOSFET package
The BSS138 N-channel logic level enhancement mode field effect transistor had a SOT-23 package, it is a surface mount package used for driver and power supply applications.
The SOT-23 is a three-terminal SMD version of the BSS138 MOSFET device, it is made up of a mixture of epoxy/plastic material.
The SOT-23 SMD version transistor package had higher heat resistance and was also very compact, these capabilities are due to the specialty of material used to build the component.
BSS138 MOSFET electrical specification explanation
In this section, we try to explain the electrical specifications of the BSS138 MOSFET device.
These specification descriptions about the BSS138 MOSFET device will be very useful for a better understanding and it is very helpful for opting for the proper application for the BSS138 MOSFET device.
The terminal voltage specs of BSS138 MOSFET are a drain to source voltage is 50V, the gate to source voltage is 20V, and the gate threshold voltage is 0.8V to 1.5V, it is the main voltage specs of this MOSFET device.
The voltage electrical specifications of this MOSFET show that this device is good at low voltage power supply and low load switching applications.
The current specs of the BSS138 MOSFET drain current value is 0.22A, it is the current value this device produces.
The pulsed drain current value is 0.88A, it is the current value produced at the condition where pulse width increases.
The current specs of BSS138 MOSFET show that it is a less load-capable device mainly used for low-load applications.
Zero gate voltage drain current
The value for zero gate voltage drain current is 0.5uA, it is the current value of BSS138 MOSFET at a specific condition.
The power dissipation value of BSS138 MOSFET is 300mW, it is the power dissipation capacity of a MOSFET device in a thermal condition.
Drain to source on-state resistance
The drain to source on-state resistance is 0.7Ω to 5.8Ω, it is the overall resistance offered by the MOSFET.
The junction temperature of the BSS138 MOSFET is –55 to +150℃.
Thermal resistance junction to ambient
The thermal resistance of BSS138 MOSFET is 350℃/W
Total gate charge
The total gate charge value of BSS138 is 1.7 to 2.4nC, it is the charge needed to trigger the MOSFET.
The input capacitance of BSS138 MOSFET is 27Pf, it is the capacitance value offered by the MOSFET at its input.
The rise time value for BSS138 MOSFET is 9 to 18ns, it is the switching time offered by the MOSFET.
The fall time value for BSS138 MOSFET is 7 to 14ns
BSS138 MOSFET DATASHEET
If you need the datasheet in pdf please click this link
BSS138 MOSFET EQUIVALENT
The MOSFET equivalent of BSS138 is IRF540N, IRF1010E, 2N7000, 2N7002, FDC666, and NTR4003.
The electrical specification and PINOUT details of these MOSFET devices are the same, the applications based on BSS138 MOSFET are low voltage and low current circuits.
We need to check and verify the PINOUT details of each MOSFET before the replacement process.
BSS138 vs 2N7000 vs MMBF170 (BC170)
In this table, we try to list the electrical specifications of BSS138, 2N7000, and MMBF170, this is a better way to understand these MOSFET devices.
|Drain to source voltage (VDS))
|Gate to source voltage (Vgs)
|Gate threshold voltage (Vg(th))
|0.8 to 1.5V
|0.8 to 3V
|0.8 to 3V
|Drain current (Id)
|Zero gate voltage drain current (IDSS)
|1 to 10uA
|Total gate charge (Qg)
|1.7 to 2.4nC
|1.4 to 2nC
|Power dissipation (PD)
|Junction temperature (TJ)
|-55 to +150°C
|-55 to +150°C
|-55 to +150°C
|Drain to source on-state resistance (RDS)
|0.7 to 5.8Ω
|1.2 to 9Ω
|1.2 to 5Ω
|Rise time (tr)
|9 to 18ns
|20 to 50pf
|24 to 40ns
Both BSS138 and 2N7000 MOSFETs have almost the same electrical specifications, they had the surface mount versions.
The MMBF170 MOSFET is the SMD version device mainly used for power supply and load driver circuits.
Characteristics curves of BSS138 MOSFET
The figure shows the On-region characteristics of BSS138 MOSFET, the graph is plotted with drain current vs drain to source voltage.
At a fixed gate to source voltage, the current increases with respect to drain to source voltage.
The figure shows the on-state resistance characteristics of BSS138 MOSFET, the graph is plotted with the drain to source on-state resistance vs drain current.
At different voltage variations, the on-state resistance value increases with voltage increases, and the drain current will be higher at initial current variations.
Applications of BSS138 MOSFET
- LOW voltage applications
- Low current applications
- Servo motor control
- Power MOSFET gate drivers