kender
Advanced Member level 4
Colleagues,
I'm making a pulsed current sink. It will be a low side constant current sink, which will consist of an OpAmp, a current sense resistor, an NPN transistor.
The output current will be up to 16mA. The voltage drop across the the transistor will be up to 100V. Pulse duration will be up to 10ms. Duty cycle will be up to 10% .
Space is at a premium in my instrument. It will be hard to fit anything larger than a SOT-23.
NPN transistors in SOT-23 are usually rated for around 200mW dissipation. Am I going to burn the NPN transistor if I have a 1.6W peak power dissipation but keep the average power dissipation under 200mW ?
Any suggestion, insight or reference is really appreciated!
- Nick
I'm making a pulsed current sink. It will be a low side constant current sink, which will consist of an OpAmp, a current sense resistor, an NPN transistor.
The output current will be up to 16mA. The voltage drop across the the transistor will be up to 100V. Pulse duration will be up to 10ms. Duty cycle will be up to 10% .
Space is at a premium in my instrument. It will be hard to fit anything larger than a SOT-23.
NPN transistors in SOT-23 are usually rated for around 200mW dissipation. Am I going to burn the NPN transistor if I have a 1.6W peak power dissipation but keep the average power dissipation under 200mW ?
Any suggestion, insight or reference is really appreciated!
- Nick