High Side Mosfet



Cached

Product NameStatusDescriptionFeaturesPackageQ-Level
Si4386DYN-Channel 30-V (D-S) MOSFETRDS(on)=0.007Ω@10V;
RDS(on)=0.0095Ω@4.5V;
Qg=11nC
SMD
SO-8

Si4634DYN-Channel 30-V (D-S) MOSFETRDS(on)=0.0052Ω@10V;
RDS(on)=0.0067Ω@4.5V;
Qg=21.5nC
SMD
SO-8

Si4660DYN-Channel 25-V (D-S) MOSFETRDS(on)=0.0058Ω@10V;
RDS(on)=0.007Ω@4.5V;
Qg=17nC
SMD
SO-8

Si7110DNN-Channel 20-V (D-S) MOSFETRDS(on)=0.0053Ω@10V;
RDS(on)=0.078Ω@4.5V;
Qg=14nC
SMD
PowerPAK 1212-8

Si7114DNN-Channel 30-V (D-S) MOSFETRDS(on)=0.0075Ω@10V;
RDS(on)=0.010Ω@4.5V;
Qg=12.5nC
SMD
PowerPAK 1212-8

Si7686DPN-Channel 30-V (D-S) MOSFETRDS(on)=0.0095Ω@10V;
RDS(on)=0.014Ω@4.5V;
Qg=9.2nC
SMD
PowerPAK SO-8

Si7804DNN-Channel 30-V (D-S) MOSFETRDS(on)=0.0185Ω@10V;
RDS(on)=0.030Ω@4.5V;
Qg=8.7nC
SMD
PowerPAK 1212-8

SiE822DFN-Channel 20-V (D-S) MOSFETRDS(on)=0.0034Ω@10V;
RDS(on)=0.0055Ω@4.5V;
Qg=24nC
SMD
PolarPAK

SiE844DFN-Channel 30-V (D-S) MOSFETRDS(on)=0.007Ω@10V;
RDS(on)=0.010Ω@4.5V;
Qg=13.1nC
SMD
PolarPAK

SiR402DPN-Channel 30-V (D-S) MOSFETRDS(on)=0.006Ω@10V;
RDS(on)=0.008Ω@4.5V;
Qg=14nC
SMD
PowerPAK SO-8

SiR462DPN-Channel 30-V (D-S) MOSFETRDS(on)=0.0079Ω@10V;
RDS(on)=0.0095Ω@4.5V;
Qg=8.8nC
SMD
PowerPAK SO-8

SiR892DPN-Channel 25-V (D-S) MOSFETRDS(on)=0.0032Ω@10V;
RDS(on)=0.0042Ω@4.5V;
Qg=20nC
SMD
PowerPAK SO-8


The MOSFETs were used as High side switches in the circuit. For driving the MOSFET in high side configuration, IR2110 gate driver IC was used. IR2110 is a High –Low side Gate Driver IC which is used with power MOSFET and IGBT. The easiest way to drive a MOSFET using the boostrap based drive is to use a dedicated high side MOSFET driver. Some drivers come with just the high-side driver while many come with both high-side and low-side drivers. IR2117, for example, is one driver that contains a single driver that can be used to drive a high-side MOSFET driver. See full list on baldengineer.com.

Here’s my schematic and board design for a simple high side switch using a P channel mosfet. It’s a simple circuit that has a input for positive and negative and an output for positive and negative connections. Pretty self explanatory. It seems like every time I go to work with mosfets I have to spend a good 5-10 minutes reminding myself how they work. So here’s a reminder to myself for the next time I go looking.

You can download the board file here. I accidentally made the pad for the mosfet as a D2PAK rather than a DPAK2. And while DPAK, DPAK2, and DPAK3 are all about the same size (almost the same size as a TO-252), the D2PAK is a much larger size. Whoops! For reference, the mosfet I’m currently using is this, where the input is 8V and using a fet with a gate to source threshold voltage of -3V and a maximum gate to source voltage of -20V. I like using a P channel mosfet for this since the circuit I care about is not connected to power. If you used a low side switch then the power would be connected and any stray connection to ground could fry everything.

The key thing here is that the negative line passes straight through which keeps everything grounded. The switch blocks the current from flowing on the high side until the switch is flipped. R2 is a resistor that pulls the gate up to the input positive voltage (8v) so that if the switch become disconnected things don’t go crazy. When the switch is open the Vgs is zero so no current flows through the fet. When the switch is closed, the gate goes to Ground and Vgs is -8V which is below (above?) the threshold so current flows through the fet.

High Side Mosfet Driver Ic

Here are a couple good resources for fets:

High Side Mosfet Drive Circuits

Sparkfun According to Pete Mosfets
BaldEngineer Mosfets
BaldEngineer High Side Switch
Jonathan Currie Youtube – Introduciton to Mosfets