A
Adam Seychell
- Jan 1, 1970
- 0
Surface mount power devices such as D-pack often have power
dissipation ratings over 80W power at Tj=25²C, but almost always these
devicea will be mounted on a PCB where the junction to ambient thermal
resistance shoots up to around 50²C/W, meaning practical power
dissipation is 1 or 2 watts. So My question is if the design requires
more than say 2 watts dissipation does that normally mean using a
through hole component with heat sink ?
When the number of paralleled SMD power MOSFETs devices become
impractical is that when through hole and heat sinks are considered ?
The application is for synchronous current doubler rectifier having an
output of 50 amps at 2.7 volts. The Ron required to limit power
dissipation at 1 watt per MOSFET would mean many paralleled devices. A
9 mOhm MOSFET can pass only 10.5 amps RMS for 1 W dissipation.
dissipation ratings over 80W power at Tj=25²C, but almost always these
devicea will be mounted on a PCB where the junction to ambient thermal
resistance shoots up to around 50²C/W, meaning practical power
dissipation is 1 or 2 watts. So My question is if the design requires
more than say 2 watts dissipation does that normally mean using a
through hole component with heat sink ?
When the number of paralleled SMD power MOSFETs devices become
impractical is that when through hole and heat sinks are considered ?
The application is for synchronous current doubler rectifier having an
output of 50 amps at 2.7 volts. The Ron required to limit power
dissipation at 1 watt per MOSFET would mean many paralleled devices. A
9 mOhm MOSFET can pass only 10.5 amps RMS for 1 W dissipation.